Map Visualization Developer'

Oracle® Spatial and Graph
Map Visualization Developer's Guide
12c Release 2 (12.2)
E87775-01
June 2017
Oracle Spatial and Graph Map Visualization Developer's Guide, 12c Release 2 (12.2)
E87775-01
Copyright © 2001, 2017, Oracle and/or its affiliates. All rights reserved.
Primary Author:
Contributors:
Chuck Murray
Joao Paiva, L.J. Qian, Jayant Sharma, Honglei Zhu
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Contents
Preface
1
Audience
xvi
Documentation Accessibility
xvi
Related Documentation
xvi
Acknowledgments
xvii
Conventions
xvii
Introduction to the Map Visualization Component
1.1
Overview of the Map Visualization Component
1.1.1
1-1
Map Visualization Component Architecture
1-2
1.2
Getting Started with the Map Visualization Component
1-3
1.3
Prerequisite Software for the Map Visualization Component
1-3
1.4
Deploying MapViewer-Based Applications with the Map Visualization
Component
1-4
Administering the Map Visualization Component
1-4
1.5
1.5.1
Logging in to the Map Visualization Component Administration Page
1-4
1.5.2
Configuring the Map Visualization Component
1-5
1.5.2.1
Specifying Logging Information
1-12
1.5.2.2
Specifying Map File Storage and Life Cycle Information
1-13
1.5.2.3
Specifying a Web Proxy
1-14
1.5.2.4
Specifying Global Map Configuration Options
1-14
1.5.2.5
Customizing the Spatial Data Cache
1-16
1.5.2.6
Specifying the Security Configuration
1-16
1.5.2.7
Registering a Custom Spatial Provider
1-18
1.5.2.8
Registering Custom Nonspatial Data Providers
1-18
1.5.2.9
Customizing SRS Mapping
1-19
1.5.2.10
Customizing WMS GetCapabilities Responses
1-19
1.5.2.11
Customizing WMTS GetCapabilities Responses
1-20
1.5.2.12
Configuring the Map Tile Server for Oracle Maps
1-21
1.5.2.13
Defining Permanent Map Data Sources
1-22
1.5.2.14
Configuring and Securing the Map Data Server for the HTML5
API
1-24
iii
1.5.3
1.6
Oracle Real Application Clusters and the Map Visualizer
1.6.1
2
1-27
1-27
1.6.1.2
Create a Map Visualizer Data Source Using a Container Data
Source
1-32
Creating a Map Visualizer Data Source Using the Oracle RAC Service
Name
1-32
Restarting the Map Visualizer
1-33
High Availability and the Map Visualizer (WebLogic Server Only)
1.7.1
1.9
1-27
Create a Container Oracle RAC Data Source
1.6.3
1.8
Creating a Container Oracle RAC Data Source for the Map Visualizer
Server
1-26
1.6.1.1
1.6.2
1.7
Performing Map Visualizer Administrative Tasks
Deploying the Map Visualizer on a Middle-Tier Cluster
Secure Map Rendering
1-33
1-33
1-34
1.8.1
How Secure Map Rendering Works
1-35
1.8.2
Getting the User Name from a Cookie
1-37
1.8.3
Authenticating Users: Options and Demo
1-38
Map Visualizer Demos and Tutorials
1-38
Map Visualization Concepts
2.1
Overview of the Map Visualizer
2-2
2.2
Styles
2-2
2.3
2.2.1
Scaling the Size of a Style (Scalable Styles)
2-4
2.2.2
Specifying a Label Style for a Bucket
2-5
2.2.3
Orienting Text Labels and Markers
2-7
2.2.3.1
Controlling Text Style Orientation
2-7
2.2.3.2
Controlling Marker Orientation
2-8
2.2.4
Making a Text Style Sticky
2-9
2.2.5
Getting a Sample Image of Any Style
2-9
2.2.6
Allowing a Text Style to Overlap or Be Overlapped
Themes
2.3.1
2-11
2-11
Predefined Themes
2-12
2.3.1.1
Styling Rules in Predefined Spatial Geometry Themes
2-13
2.3.1.2
How the Map Visualizer Formulates a SQL Query for a Styling
Rule
2-15
2.3.1.3
Styling Rules with Binding Parameters
2-16
2.3.1.4
Applying Multiple Rendering Styles in a Single Styling Rule
2-17
2.3.1.5
Using Multiple Rendering Styles with Scale Ranges
2-18
2.3.1.6
Caching of Predefined Themes
2-18
2.3.1.7
Feature Labels and Internationalization
2-19
2.3.1.8
Primary and Secondary Labels for Linear Features
2-22
2.3.2
JDBC Themes
2-22
iv
2.3.2.1
Defining a Point JDBC Theme Based on Two Columns
2-24
2.3.2.2
Storing Complex JDBC Themes in the Database
2-25
2.3.3
Image Themes
2.3.3.1
2.3.4
GeoRaster Themes
2-28
Creating Predefined GeoRaster Themes
2-30
2.3.4.2
Using Bitmap Masks with GeoRaster Themes
2-35
2.3.4.3
Reprojection of GeoRaster Themes
2-36
2.3.4.4
Virtual Mosaic Themes
2-36
Network Themes
2-38
2.3.5.1
Creating Predefined Network Themes
2-40
2.3.5.2
Using the Map Visualizer for Network Analysis
2-41
2.3.6
Topology Themes
2.3.6.1
2.3.7
2.3.8
Creating Predefined Topology Themes
WFS Themes
2.3.7.1
Creating Predefined WFS Themes
WMTS Themes
2-42
2-44
2-45
2-48
2-49
2.3.8.1
How the tile_resizing_option Attribute Works
2-53
2.3.8.2
snap_to_tile_scale and tile_resizing_option Attribute Usage
Guidelines
2-54
Creating Predefined WMTS Themes
2-55
2.3.8.3
2.3.9
Custom Geometry Themes
2-56
2.3.10
Annotation Text Themes
2-61
2.3.11
LRS (Linear Referencing System) Themes
2-65
2.3.12
Thematic Mapping
2-68
2.3.12.1
2.3.13
2.5
2-27
2.3.4.1
2.3.5
2.4
Creating Predefined Image Themes
2-26
Thematic Mapping Using External Attribute Data
Attributes Affecting Theme Appearance
Maps
2-74
2-77
2-78
2.4.1
Map Size and Scale
2-79
2.4.2
Map Legend
2-81
Data Sources
2.5.1
Catalog Data Sources
2-85
2-86
2.5.1.1
Export the Necessary Metadata from an Oracle Database
2-86
2.5.1.2
Export the Necessary Spatial Tables
2-87
2.5.1.3
Edit the Map Visualizer Configuration File to Add the Catalog Data
Source
2-88
Restart the Map Visualizer Server
2-88
2.5.1.4
2.6
How a Map Is Generated
2-88
2.7
Cross-Schema Map Requests
2-90
2.8
Workspace Manager Support in the Map Visualizer
2-92
2.9
Map Visualizer Metadata Views
2-93
2.9.1
xxx_SDO_STYLES Views
2-95
v
2.9.2
xxx_SDO_THEMES Views
2-96
2.9.3
xxx_SDO_MAPS Views
2-97
2.9.4
xxx_SDO_CACHED_MAPS Views
2-97
2.10
3
Oracle Maps
2-98
2.10.1
Overview of Oracle Maps
2-98
2.10.2
Architecture for Oracle Maps Applications
2-99
Map Visualization Servers
3.1
3.2
Map Visualizer Map Data Server
3-1
3.1.1
Domains and Map Data Server URL Patterns
3-1
3.1.2
Map Data Server Request Parameters
3-2
3.1.2.1
Getting Data from a Predefined Geometry Theme
3-2
3.1.2.2
Getting Data from a JDBC Theme
3-4
3.1.2.3
Getting Annotation Text from a JDBC Theme
3-4
3.1.2.4
Getting Topology Data
3-6
3.1.3
Interpreting Data Returned from the Map Data Server
3-10
3.1.4
Map Data Server Error Handling
3-12
Map Tile Server
3.2.1
Map Tile Server Concepts
3-12
3-14
3.2.1.1
Map Tile Layers and Map Tile Sources
3-14
3.2.1.2
Storage of Map Image Tiles
3-14
3.2.1.3
Coordinate System for Map Tiles
3-16
3.2.1.4
Tile Mesh Codes
3-17
3.2.1.5
Map Tile Requests
3-18
3.2.1.6
Tiling Rules
3-19
3.2.1.7
Tile Background Color and Out-of-Bounds Color
3-19
3.2.2
Map Tile Server Configuration
3-20
3.2.2.1
Global Map Tile Server Configuration
3-20
3.2.2.2
Map Tile Layer Configuration
3-20
3.2.2.3
Map Tile Storage Schemes: Internal Mesh Code or XYZ
3-28
3.2.2.4
Creating a Map Tile Layer Using an External Web Map Source
3-29
3.2.3
Map Cache Auto-Update
3.2.3.1
3-30
Add the <dirty_tile_auto_update> element to the
mapViewerConfig.xml configuration file
3-30
3.2.3.2
Add the <auto_update> element to tile layer definition
3-31
3.2.3.3
Create the dirty MBR table, base tables' log table, and triggers
3-32
3.2.3.4
Start the map visualizer server and test the map cache autoupdate feature
3-37
3.2.4
UTFGrid for Map Tiles: Including Text Information About Features
3-37
3.2.4.1
Enabling the UTFGrid Option for a Tile Layer
3-38
3.2.4.2
Encoding a Key and Decoding a Grid Cell's Value
3-39
vi
3.2.4.3
3.2.5
4
Oracle Maps JavaScript API
4.1.1
4.2
4.3
4.4
Creating the Client Application with the API
Using Google Maps and Bing Maps
3-44
4-1
4-2
4-4
4-6
4-7
4.3.1
Defining Google Maps and Bing Maps Tile Layers on the Client Side
4-8
4.3.2
Defining the Built-In Map Tile Layers on the Server Side
4-8
Transforming Data to a Spherical Mercator Coordinate System
4.4.1
4.5
About the Oracle Maps JavaScript API
Developing Oracle Maps Applications
4.2.1
Creating a Transformation Rule to Skip Datum Conversion
Using Dynamic Tile Layers
4.5.1
4-9
4-10
4-11
Creating a Universe and Configuration Instance for a Dynamic Tile
Layer
4-11
4.5.2
Creating a Dynamic Tile Layer Using a Base Map
4-11
4.5.3
Creating a Dynamic Tile Layer Using Predefined Themes
4-12
4.5.4
Creating a Dynamic Tile Layer Using Spatial Tables Directly
4-13
4.5.5
Creating a Dynamic Tile Layer Using Third Party Map Services
4-14
4.5.6
Dynamic Tile Layer Use Case
4-15
Oracle Map Builder Tool
5.1
Running Oracle Map Builder
5.1.1
5.2
A
External Map Source Adapter
3-39
Oracle Maps
4.1
5
Building a UTFGrid Test Case
Java Libraries for Theme Creation with GDAL and Teradata
Oracle Map Builder User Interface
5-1
5-2
5-2
XML Format for Styles, Themes, Base Maps, and Map Tile Layers
A.1
Color Styles
A-2
A.2
Marker Styles
A-3
A.2.1
Vector Marker Styles
A-4
A.2.2
Image Marker Styles
A-5
A.2.3
TrueType Font-Based Marker Styles
A-5
A.2.4
Using Marker Styles on Lines
A-5
A.3
Line Styles
A-6
A.4
Area Styles
A-8
A.5
Text Styles
A-8
A.6
Advanced Styles
A-9
A.6.1
Bucket Styles
A-10
vii
B
C
A.6.1.1
Collection-Based Buckets with Discrete Values
A-11
A.6.1.2
Individual Range-Based Buckets
A-11
A.6.1.3
Equal-Ranged Buckets
A-12
A.6.2
Color Scheme Styles
A-12
A.6.3
Variable Marker Styles
A-13
A.6.4
Dot Density Marker Styles
A-14
A.6.5
Bar Chart Marker Styles
A-14
A.6.6
Collection Styles
A-15
A.6.7
Variable Pie Chart Styles
A-16
A.6.8
Heat Map Styles
A-16
A.7
Themes: Styling Rules
A-18
A.8
Base Maps
A-23
A.9
Map Tile Layers
A-24
Creating and Registering a Custom Spatial Data Provider
B.1
Implementing the Spatial Provider Class
B-2
B.2
Registering the Spatial Provider with the Map Visualization Component
B-5
B.3
Rendering the External Spatial Data
B-6
OGC WMS Support in the Map Visualization Component
C.1
C.2
Setting Up the WMS Interface for the Map Visualization Component
C-1
C.1.1
Required Files
C-2
C.1.2
Data Source Named wms
C-2
C.1.3
SDO to EPSG SRID Mapping File
C-2
WMS Specification and Corresponding Map Visualization Component
Concepts
C.2.1
Supported GetMap Request Parameters
C-3
C-3
C.2.1.1
BASEMAP Parameter (Map Visualization Component-Only)
C-4
C.2.1.2
BBOX Parameter
C-5
C.2.1.3
BGCOLOR Parameter
C-5
C.2.1.4
DATASOURCE Parameter (Map Visualization Component-Only)
C-5
C.2.1.5
DYNAMIC_STYLES Parameter (Map Visualization ComponentOnly)
C-5
C.2.1.6
EXCEPTIONS Parameter
C-5
C.2.1.7
FORMAT Parameter
C-5
C.2.1.8
HEIGHT Parameter
C-6
C.2.1.9
LAYERS Parameter
C-6
C.2.1.10
C.2.1.11
LEGEND_REQUEST Parameter (Map Visualization
Component-Only)
C-6
MVTHEMES Parameter (Map Visualization Component-Only)
C-6
viii
C.2.1.12
REQUEST Parameter
C-6
C.2.1.13
SERVICE Parameter
C-6
C.2.1.14
SRS (1.1.1) or CRS (1.3.0) Parameter
C-7
C.2.1.15
STYLES Parameter
C-7
C.2.1.16
TRANSPARENT Parameter
C-7
C.2.1.17
VERSION Parameter
C-7
C.2.1.18
WIDTH Parameter
C-7
C.2.2
Supported GetCapabilities Request and Response Features
C-7
C.2.3
Supported GetFeatureInfo Request and Response Features
C-10
C.2.3.1
GetMap Parameter Subset for GetFeatureInfo Requests
C-11
C.2.3.2
EXCEPTIONS Parameter
C-11
C.2.3.3
FEATURE_COUNT Parameter
C-11
C.2.3.4
INFO_FORMAT Parameter
C-11
C.2.3.5
QUERY_LAYERS Parameter
C-12
C.2.3.6
QUERY_TYPE Parameter (Map Visualization Component-Only)
C-12
C.2.3.7
RADIUS Parameter (Map Visualization Component-Only)
C-12
C.2.3.8
UNIT Parameter (Map Visualization Component-Only)
C-12
C.2.3.9
X and Y or I and J Parameters
C-12
C.2.3.10
C.3
Adding a WMS Map Theme
C-12
C-13
C.3.1
XML API for Adding a WMS Map Theme
C-13
C.3.2
Predefined WMS Map Theme Definition
C-16
C.3.3
Authentication with WMS Map Themes
C-16
C.3.4
Customizing GetCapabilities Responses: Additional Options
C-18
C.3.4.1
Custom WMS Capabilities Parameters (<custom_parameters>
Element)
C-18
Custom WMS Capabilities Service Attributes
(<service_attributes> Element)
C-19
C.3.4.3
Custom WMS Layer Attributes (<layer_attributes> Element)
C-19
C.3.4.4
Custom WMS Feature Information (<get_feature_info> Element)
C-22
C.3.4.2
D
Specifying Attributes to Be Queried for a GetFeatureInfo
Request
OGC WMTS Support in the Map Visualization Component
D.1
WMTS Service for MapViewer
D-1
D.2
WMTS Operations
D-3
D.2.1
GetCapabilities Operation Support
D.2.2
GetTile Operation Support
D.2.2.1
D.2.3
Map Tiles in WMTS Layer and in Map Cache Tile Layer
GetFeatureInfo Operation Support
D-3
D-11
D-12
D-13
D.2.3.1
OGC GetFeatureInfo Request
D-15
D.2.3.2
MapViewer GetFeatureInfo Request at an (x,y) Point
D-16
ix
D.2.3.3
D.3
MapViewer GetFeatureInfo Request within a Bounding Box
Preparing the WMTS Service for MapViewer
D-17
D-19
D.3.1
Prepare Predefined Geometry Themes
D-19
D.3.2
Prepare the Base Map
D-19
D.3.3
Prepare Tile Layers
D-19
D.3.4
Publish Tile Layers in the wmtsConfig.xml Policy File
D-22
D.3.5
Verify the MapViewer WMTS Service
D-23
Index
x
List of Examples
1-1
Sample Map Visualization Component Configuration File
1-5
1-2
Configuring the mds.xml File
1-25
1-3
PL/SQL Package for Secure Map Rendering
1-35
1-4
View for Secure Map Rendering
1-36
1-5
Data Source Definition for Secure Map Rendering
1-37
1-6
Data Source Definition Specifying Cookie Name
1-37
2-1
Scalable Marker Style
2-4
2-2
Scalable Line Style
2-4
2-3
Advanced Style with Text Label Style for Each Bucket
2-5
2-4
Labeling an Oriented Point
2-8
2-5
Text Style with Sticky Attribute
2-9
2-6
XML Definition of Styling Rules for an Airport Theme
2-13
2-7
Styling Rules Using the <rendering> Element
2-17
2-8
Theme Styling Rules with Stacked Styles
2-18
2-9
JDBC Theme in a Map Request
2-23
2-10
JDBC Theme Based on Columns
2-24
2-11
JDBC Theme Based on Columns, with Query Window
2-24
2-12
Complex Query in a Predefined Theme
2-25
2-13
Creating a Predefined Image Theme
2-27
2-14
GeoRaster Theme Containing a SQL Statement
2-30
2-15
GeoRaster Theme Specifying a Raster ID and Raster Data Table
2-30
2-16
Creating a Predefined GeoRaster Theme
2-31
2-17
Preparing GeoRaster Data for Use with a GeoRaster Theme
2-31
2-18
Bitmap Mask in Predefined GeoRaster Theme
2-36
2-19
Reprojection Mode in Predefined GeoRaster Theme
2-36
2-20
Network Theme
2-40
2-21
Creating a Predefined Network Theme
2-40
2-22
Network Theme for Shortest-Path Analysis
2-42
2-23
Network Theme for Within-Cost Analysis
2-42
2-24
Topology Theme
2-44
2-25
Topology Theme Using Debug Mode
2-44
2-26
Creating a Predefined Topology Theme
2-45
2-27
WFS Request with a Dynamic WFS Theme
2-47
2-28
Creating a Predefined WFS Theme
2-48
2-29
Map Request with Predefined WFS Theme
2-48
xi
2-30
Request with a Dynamic WMTS Theme
2-55
2-31
Creating a Predefined WMTS Theme
2-55
2-32
Map Request with Predefined WMTS Theme
2-56
2-33
Defining a Dynamic Custom Geometry Theme
2-59
2-34
Storing a Predefined Custom Geometry Theme
2-59
2-35
Styling Rules for a Predefined Annotation Text Theme
2-63
2-36
Dynamic Annotation Text Theme Definition
2-63
2-37
Dynamic Annotation Text Theme with Default Annotation Column
2-63
2-38
Script to Generate Annotation Text Data
2-63
2-39
Creating an LRS Theme
2-67
2-40
Map Request with Predefined LRS Theme
2-68
2-41
XML Definition of Styling Rules for an Earthquakes Theme
2-71
2-42
Advanced Style Definition for an Earthquakes Theme
2-71
2-43
Mapping Population Density Using a Graduated Color Scheme
2-72
2-44
Mapping Average Household Income Using a Graduated Color Scheme
2-72
2-45
Mapping Average Household Income Using a Color for Each Income Range
2-73
2-46
Advanced Style Definition for Gasoline Stations Theme
2-74
2-47
Styling Rules of Theme Definition for Gasoline Stations
2-74
2-48
Nonspatial (External) Data Provider Implementation
2-75
2-49
XML Definition of a Base Map
2-79
2-50
Legend Included in a Map Request
2-83
2-51
Map Request with Automatic Legend
2-84
2-52
Automatic Legend with Themes Specified
2-84
2-53
Cross-Schema Access: Geometry Table
2-91
2-54
Cross-Schema Access: GeoRaster Table
2-91
2-55
Cross-Schema Access: Topology Feature Table
2-91
2-56
Cross-Schema Access: Network Tables
2-92
2-57
Workspace Manager-Related Attributes in a Map Request
2-93
2-58
Finding Styles Owned by the MDSYS Schema
2-95
3-1
Streaming Tiles Without Storing Them
3-16
3-2
XML Definition of an Internal Map Tile Layer Based on a Base Map
3-22
3-3
XML Definition of an Internal Map Tile Layer Based on Themes
3-22
3-4
XML Definition of an External Map Tile Layer
3-23
3-5
External Map Source Adapter
3-45
3-6
MapSourceAdapter.getTileImageBytes Implementation
3-46
4-1
Transformation Rules Defined in the csdefinition.sql Script
4-10
B-1
Implementing the Spatial Provider Class
B-2
xii
B-2
Map Request to Render External Spatial Data
B-6
C-1
GetMap Requests
C-3
C-2
GetCapabilities Response (Excerpt)
C-9
C-3
GetFeatureInfo Request
C-10
C-4
GetFeatureInfo Response
C-10
C-5
Adding a WMS Map Theme (XML API)
C-15
C-6
Creating a Predefined WMS Theme
C-16
C-7
WMS Theme with Authentication Specified
C-17
C-8
Custom WMS Layer Attributes
C-20
C-9
GetCapabilities Response with Custom Attributes
C-21
D-1
WMTS Policy File (wmtConfig.xml)
D-2
D-2
Tile Layer Definition in the Data Source
D-2
D-3
Response from GetCapabilities Request in KVP Encoding
D-4
D-4
Response from GetCapabilities Request in REST Encoding
D-9
D-5
Base Map Definition for Tile Layer TEST_TL
D-14
D-6
Theme Names and Styling Rules for Tile Layer TEST_TL
D-14
D-7
Response from OGC GetFeatureInfo Request
D-15
D-8
Response from MapViewer GetFeatureInfo Request within a Bounding Box
D-18
D-9
Tile Definition of Scale Set GlobalCRS84Scale
D-20
D-10
Tile Definition of Scale Set GlobalCRS84Pixel
D-20
D-11
Tile Definition of Scale Set GoogleCRS84Quad
D-21
D-12
Tile Definition of Scale Set GoogleMapsCompatible
D-22
D-13
Publishing Tile Layers
D-23
xiii
List of Figures
1-1
Map Visualization Component Architecture
1-3
1-2
Selecting the Server Instance
1-28
1-3
Displaying JDBC Data Sources
1-28
1-4
Creating a GridLink Data Source
1-29
1-5
Selecting the Server Instance
1-30
1-6
Displaying JDBC Data Sources
1-30
1-7
Creating a Multi Data Source
1-31
2-1
Varying Label Styles for Different Buckets
2-6
2-2
Map Display of the Label for an Oriented Point
2-8
2-3
Oriented Marker
2-9
2-4
Sample Image of a Specified Marker Style
2-10
2-5
Sample Image of a Specified Line Style
2-10
2-6
Text Style with allow-overlap="true"
2-11
2-7
Specifying a Resource Bundle for a Theme
2-21
2-8
Image Theme and Other Themes Showing Boston Roadways
2-26
2-9
snap_to_tile_scale Attribute
2-52
2-10
unbiased tile_resizing_option Value
2-53
2-11
expand_biased tile_resizing_option Value
2-53
2-12
contract_biased tile_resizing_option Value
2-54
2-13
Thematic Mapping: Advanced Style and Theme Relationship
2-69
2-14
Map with Legend
2-82
2-15
Architecture for Oracle Maps Applications
2-99
3-1
Workflow of the Map Tile Server
3-13
3-2
Tiling with a Longitude/Latitude Coordinate System
3-17
3-3
Tile Mesh Codes
3-18
3-4
Internal Mesh Code and XYZ Map Tile Storage Schemes
3-28
5-1
Oracle Map Builder Main Window
5-3
A-1
Shield Symbol Marker for a Highway
A-6
A-2
Text Style with White Background
A-9
A-3
Heat Map Showing Pizza Restaurant Concentration
B-1
Map Image Using Custom Geometry Theme and External Spatial Data
C-1
Using Map Builder to Specify Authentication with a WMS Theme
C-17
D-1
Image Tile as Response to GetTile Request
D-11
D-2
Response from MapViewer GetFeatureInfo Request at an (x,y) Point
D-17
D-3
Bounding Box for MapViewer GetFeatureInfo Request
D-18
A-17
B-7
xiv
List of Tables
2-1
Style Types and Applicable Geometry Types
2-3
2-2
Table Used with Gasoline Stations Theme
2-70
2-3
xxx_SDO_STYLES Views
2-95
2-4
xxx_SDO_THEMES Views
2-96
2-5
xxx_SDO_MAPS Views
2-97
2-6
xxx_SDO_CACHED_MAPS Views
2-97
xv
Preface
Preface
Oracle Spatial and Graph Map Visualization Developer's Guide describes how to use
the Oracle Spatial and Graph map visualization component (sometimes referred to as
the map visualizer or the visualizer), a tool that renders maps showing different kinds
of spatial data.
Topics:
•
Audience
•
Documentation Accessibility
•
Related Documentation
•
Acknowledgments
•
Conventions
Audience
This document is intended primarily for programmers who develop applications that
require maps to be drawn. You should understand Oracle Database concepts and the
major concepts associated with XML, including DTDs. You should also be familiar with
Oracle Spatial and Graph concepts, or at least have access to Oracle Spatial and
Graph Developer's Guide.
This document is not intended for end users of websites or client applications.
Documentation Accessibility
For information about Oracle's commitment to accessibility, visit the Oracle
Accessibility Program website at http://www.oracle.com/pls/topic/lookup?
ctx=acc&id=docacc.
Access to Oracle Support
Oracle customers that have purchased support have access to electronic support
through My Oracle Support. For information, visit http://www.oracle.com/pls/topic/
lookup?ctx=acc&id=info or visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=trs
if you are hearing impaired.
Related Documentation
For more information, see the following documents in the Oracle Database
documentation set:
•
Oracle Spatial and Graph Developer's Guide
•
Oracle Spatial and Graph GeoRaster Developer's Guide
xvi
Preface
•
Oracle Spatial and Graph Topology Data Model and Network Data Model Graph
Developer's Guide
•
Oracle Database Concepts
•
Oracle Database SQL Language Reference
Acknowledgments
This product includes color specifications and designs developed by Cynthia Brewer
(http://colorbrewer.org/).
Use of OpenStreetMap (OSM) tiles is subject to their copyright (© OpenStreetMap
contributors) and terms of use. For more information, see http://
www.openstreetmap.org/copyright and http://wiki.openstreetmap.org/wiki/
Tile_usage_policy.
The MVDEMO dataset is from Natural Earth (http://www.naturalearthdata.com). See
the terms of use at: http://www.naturalearthdata.com/about/terms-of-use/
Conventions
The following text conventions are used in this document:
Convention
Meaning
boldface
Boldface type indicates graphical user interface elements associated
with an action, or terms defined in text or the glossary.
italic
Italic type indicates book titles, emphasis, or placeholder variables for
which you supply particular values.
monospace
Monospace type indicates commands within a paragraph, URLs, code
in examples, text that appears on the screen, or text that you enter.
xvii
1
Introduction to the Map Visualization
Component
The Oracle Spatial and Graph map visualization component (sometimes referred to
the visualization component) is a programmable tool for rendering maps using spatial
data managed by Oracle Spatial and Graph.
The map visualization component provides tools that hide the complexity of spatial
data queries and cartographic rendering, while providing customizable options for
more advanced users. These tools can be deployed in a platform-independent manner
and are designed to integrate with map-rendering applications.
Topics:
•
Overview of the Map Visualization Component
The map visualization component enables developers to incorporate highly
interactive maps and spatial analysis into business applications.
•
Getting Started with the Map Visualization Component
To get started, follow these steps.
•
Prerequisite Software for the Map Visualization Component
To use the map visualization component, you must have the following software.
•
Deploying MapViewer-Based Applications with the Map Visualization Component
If you have any MapViewer-based applications, you can deploy them with the map
visualization component.
•
Administering the Map Visualization Component
This topic introduces the map visualization component Administration page and
some administrative and configuration tasks that you can perform, such as adding
new data sources, managing map tile layers used by Oracle Maps, and setting
logging levels.
•
Oracle Real Application Clusters and the Map Visualizer
When the database is an Oracle Real Application Cluster (Oracle RAC), you can
connect to the Oracle RAC database using either of the following options.
•
High Availability and the Map Visualizer (WebLogic Server Only)
Users can benefit from the high availability features of Oracle WebLogic Server.
•
Secure Map Rendering
You can implement secure map rendering based on a web user's identity.
•
Map Visualizer Demos and Tutorials
Several map visualizer demos and tutorials are included in a separate application
archive named mvdemo.ear, and deployed to the same Java EE container where
mapviewer.ear is deployed.
1.1 Overview of the Map Visualization Component
The map visualization component enables developers to incorporate highly interactive
maps and spatial analysis into business applications.
1-1
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Overview of the Map Visualization Component
Application content can be combined with maps and data from a variety of web
services and data formats such as GeoJSON. It is deployed in a Java EE container or
in the Oracle Java Cloud Service.
The map visualization component includes the following:
•
A map rendering engine to expose cartographic render functions to web
applications.
•
A suite of application programming interfaces (APIs) that allow programmable
access to visualization features. These APIs include XML, Java, and an HTML5based JavaScript API.
•
A graphical map builder tool that enables you to create map symbols, define
spatial data rendering rules, and create and edit map visualization component
objects.
•
Oracle Maps, which includes map cache and FOI (feature of interest) servers that
facilitate the development of interactive geospatial web applications.
•
Packaged content for admin areas (countries, states, counties, and so on) as
JSON files.
The core rendering engine connects to the Oracle database through Java Database
Connectivity (JDBC). It also reads the map metadata (such as map definitions, styling
rules, and symbology created through the Map Builder tool) from the database, and
applies the metadata to the retrieved spatial data during rendering operations.
The JavaScript API enables you to create highly interactive web applications that use
the Oracle Maps feature of the map visualization component.
The Map Builder tool simplifies the process of creating and managing map, theme,
and symbology metadata in a spatial database. For information about this tool, see
Oracle Map Builder Tool.
Oracle Maps, built on core map visualization component features, uses a map tile
server that caches map image tiles, and a feature of interest (FOI) server that streams
live data out of a database to be displayed as interactive features on a map. You can
use the HTML5-based JavaScript API with Oracle Maps to provide sophisticated
mapping solutions. Oracle Maps also allows for advanced customization and querying
capabilities.
The map visualization component supports two-dimensional vector geometries stored
in Oracle Spatial and Graph, as well as GeoRaster data and data in the Oracle Spatial
and Graph topology and network data models. The map visualization component is
also an Open Geospatial Consortium (OGC)-compliant web map service (WMS) and
web map tile service (WMTS) server.
The
•
Map Visualization Component Architecture
1.1.1 Map Visualization Component Architecture
The following figure illustrates the architecture of the map visualization component.
1-2
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Getting Started with the Map Visualization Component
Figure 1-1
Map Visualization Component Architecture
As shown in the preceding figure:
•
The map visualization component can communicate with a client web browser or
application or external web services using the HTTP protocol.
•
With a client web browser or application, it communicates using HTTP protocol
with the map visualization rendering engine in a JEE container or the Java cloud
service.
•
It performs spatial data access (reading and writing Oracle Spatial and Graph
data) through JDBC calls to the database or the database cloud service.
•
The database or database cloud service includes Oracle Spatial and Graph, as
well as mapping metadata.
1.2 Getting Started with the Map Visualization Component
To get started, follow these steps.
1.
Either before or after you install and deploy the map visualization component, read
Map Visualization Concepts to be sure you understand important terms and
concepts.
2.
Ensure that you have the prerequisite software (see Prerequisite Software for the
Map Visualization Component).
3.
Install (if necessary) and deploy the map visualization component.
4.
Use the map visualization component for some basic tasks. For example, create
an Oracle Maps application (see Oracle Maps).
5.
Optionally, use the Map Builder tool (described in Oracle Map Builder Tool) to
familiarize yourself with styles, themes, and maps, and the options for each, and
optionally to preview spatial data.
1.3 Prerequisite Software for the Map Visualization
Component
To use the map visualization component, you must have the following software.
1-3
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Deploying MapViewer-Based Applications with the Map Visualization Component
•
A supported JEE server (see http://www.oracle.com/technetwork/database/
options/spatialandgraph/documentation/jee-server-support-3659112.html)
•
Java SDK 1.8 or later
The map visualization component also supports the headless AWT mechanism in
J2SE SDK, which enables the visualization component to run on Linux or UNIX
systems without setting any X11 DISPLAY variable. To enable AWT headless mode on
Linux or UNIX systems, specify the following in the command line to start the map
visualization component:
-Djava.awt.headless=true
1.4 Deploying MapViewer-Based Applications with the Map
Visualization Component
If you have any MapViewer-based applications, you can deploy them with the map
visualization component.
If you want to continue to use your existing MapViewer configuration, follow the
instructions in this section.
Applications written using the MapViewer V2 API will work with the map visualization
component.
(You can also use an existing MapViewer configuration in WebLogic Server on Oracle
Fusion Middleware Release 12.2.1.x.0 and later.)
1.5 Administering the Map Visualization Component
This topic introduces the map visualization component Administration page and some
administrative and configuration tasks that you can perform, such as adding new data
sources, managing map tile layers used by Oracle Maps, and setting logging levels.
•
Logging in to the Map Visualization Component Administration Page
•
Configuring the Map Visualization Component
•
Performing Map Visualizer Administrative Tasks
1.5.1 Logging in to the Map Visualization Component Administration
Page
After you have verified that the map visualization component is running properly, it is
suggested that you log in to the map visualization component Administration page. To
do this, go first to the map visualization component Welcome page, which is typically
http://<host>:<port>/mapviewer, where <host> and <port> should be replaced by the
correct value for your installation.
Click the Admin link at the top right to display the map visualization component
Administration page.
You can use this administration page to perform administrative tasks, such as clearing
cached data, creating tile layers, managing tile layers, and restarting the server (use
the Monitoring link to restart).
1-4
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1.5.2 Configuring the Map Visualization Component
If the default configuration settings for running the map visualization component are
not adequate, you can configure the map visualization component by editing the
visualization component configuration file, mapViewerConfig.xml, which is located in
the $MAPVIEWER_HOME/WEB-INF/conf directory. To modify this file, you can use a text
editor, or you can use the map visualization component Administration page.
After you modify this file, you must restart the container to have the changes take
effect; however, you can instead use the map visualization component Administration
page to restart only the map visualization component servlet (instead of the entire
Java EE instance, which may have other applications deployed and running) if you
installed the map visualization component with a standalone Glassfish instance.
The map visualization component configuration file defines the following information in
XML format:
•
Logging information, defined either through container-controlled logging
(recommended) or in the <logging> element (see Specifying Logging Information)
•
Map image file information, defined in the <save_images_at> element (see
Specifying Map File Storage and Life Cycle Information)
•
Web proxy information for accessing external information across a firewall, defined
in the <web_proxy> element (see Specifying a Web Proxy)
•
Global map "look and feel" configuration, defined in the <global_map_config>
element (see Specifying Global Map Configuration Options)
•
Internal spatial data cache settings, defined in the <spatial_data_cache> element
(see Customizing the Spatial Data Cache)
•
Permanent map data sources, defined in the <map_data_source> element (see
Defining Permanent Map Data Sources)
•
Security configurations, defined in the <security_config> element
•
WMS services configurations, defined in the <wms_config> element
•
External attribute data provider registration, defined in <ns_data_provider>
elements
•
Map tile server configurations, defined in the <map_tile_server> element
•
UTF grid lifecycle parameters, defined in the <utfgrid_life_cycle> element
•
External spatial data provider registration, defined in the <s_data_provider>
element
•
Map data sources, defined in the <map_data_source> element
•
Map data server stream parameters, defined in the <mds_config> element
•
OAM logout parameters, defined in the <oam_logout> element
All path names in the mapViewerConfig.xml file are relative to the directory in which the
file is stored, unless otherwise specified.
Example 1-1
Sample Map Visualization Component Configuration File
Example 1-1 shows a sample mapViewerConfig.xml file.
1-5
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<?xml version="1.0" ?>
<!-- This is the configuration file for the map visualization component. -->
<!-- Note: All paths are resolved relative to this directory (where
this config file is located), unless specified as an absolute
path name.
-->
<MapperConfig>
<!-- ****************************************************************** -->
<!-- ************************ Logging Settings ************************ -->
<!-- ****************************************************************** -->
<!-- Uncomment the following to modify logging. Possible values are:
log_level = "fatal"|"error"|"warn"|"info"|"debug"|"finest"
default: info) ;
log_thread_name = "true" | "false" ;
log_time = "true" | "false" ;
one or more log_output elements.
-->
<!-<logging log_level="info" log_thread_name="false"
log_time="true">
<log_output name="System.err" />
<log_output name="../log/mapviewer.log" />
</logging>
-->
<!-- ****************************************************************** -->
<!-- ********************** Map Image Settings ************************ -->
<!-- ****************************************************************** -->
<!-- Uncomment the following only if you want generated images to
be stored in a different directory, or if you want to customize
the life cycle of generated image files.
By default, all maps are generated under
$ORACLE_HOME/lbs/mapviewer/web/images.
Images location-related attributes:
file_prefix: image file prefix, default value is "omsmap"
url: the URL at which images can be accessed. It must match the 'path'
attribute below. Its default value is "%HOST_URL%/mapviewer/images"
path: the corresponding path in the server where the images are
saved; default value is "%ORACLE_HOME%/lbs/mapviewer/web/images"
Images life cycle-related attributes:
life: the life period of generated images, specified in minutes.
If not specified or if the value is 0, images saved on disk will
never be deleted.
recycle_interval: this attribute specifies how often the recycling
of generated map images will be performed. The unit is minute.
The default interval (when not specified or if the value is 0)
is 8*60, or 8 hours.
-->
<!-<save_images_at file_prefix="omsmap"
url="http://mypc.mycorp.com:8888/mapviewer/images"
path="../web/images"
/>
1-6
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-->
<!-- ****************************************************************** -->
<!-- ********************* IP Monitoring Settings ********************* -->
<!-- ****************************************************************** -->
<!-- Uncomment the following to enable IP filtering for administrative
requests.
Note:
- Use <ips> and <ip_range> to specify which IPs (and ranges) are allowed.
Wildcard form such as 20.* is also accepted. Use a comma-delimited
list in <ips>.
- Use <ips_exclude> and <ip_range_exclude> for IPs and IP ranges
prohibited from accessing eLocation.
- If an IP falls into both "allowed" and "prohibited" categories, it is
prohibited.
- If you put "*" in an <ips> element, then all IPs are allowed, except
those specified in <ips_exclude> and <ip_range_exclude>.
On the other hand, if you put "*" in an <ips_exclude> element, no one
will be able to access the map visualization component (regardless of whether
an IP is in
<ips> or <ip_range>).
- You can have multiple <ips>, <ip_range>, <ips_exclude>, and
<ip_range_exclude> elements under <ip_monitor>.
- If no <ip_monitor> element is present in the XML configuration
file, then no IP filtering will be performed (all allowed).
- The way the map visualization component determines if an IP is allowed is:
if(IP filtering is not enabled) then allow;
if(IP is in exclude-list) then not allow;
else if(IP is in allow-list) then allow;
else not allow;
-->
<!-<ip_monitor>
<ips> 138.1.17.9, 138.1.17.21, 138.3.*, 20.* </ips>
<ip_range> 24.17.1.3 - 24.17.1.20 </ip_range>
<ips_exclude> 138.3.29.* </ips_exclude>
<ip_range_exclude>20.22.34.1 - 20.22.34.255</ip_range_exclude>
</ip_monitor>
-->
<!-<!-<!-<!--
****************************************************************** -->
********************** Web Proxy Setting ************************ -->
****************************************************************** -->
Uncomment and modify the following to specify the web proxy setting.
This is only needed for passing background image URLs to
the map visualization component in map requests or for setting a logo image
URL, if
such URLs cannot be accessed without the proxy.
-->
<!-<web_proxy host="www-proxy.my_corp.com" port="80" />
1-7
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-->
<!-- ****************************************************************** -->
<!-- *********************** Security Configuration ******************* -->
<!-- ****************************************************************** -->
<!-- Here you can set various security related configurations of the map
visualization component.
-->
<security_config>
<disable_direct_info_request> false </disable_direct_info_request>
</security_config>
<!-<!-<!-<!--
****************************************************************** -->
*********************** Global Map Configuration ***************** -->
****************************************************************** -->
Uncomment and modify the following to specify systemwide parameters
for generated maps. You can specify your copyright note, map title, and
an image to be used as a custom logo shown on maps. The logo image must
be accessible to this map visualization component and in either GIF or JPEG
format.
Notes:
- To disable a global note or title, specify an empty string ("") for
the text attribute of <note> and <title> element.
- position specifies a relative position on the map where the
logo, note, or title will be displayed. Possible values are
NORTH, EAST, SOUTH, WEST, NORTH_EAST, SOUTH_EAST,
SOUTH_WEST, NORTH_WEST, and CENTER.
- image_path specifies a file path or a URL (starts with "http://")
for the image.
<rendering> element attributes:
- Local geodetic data adjustment: If allow_local_adjustment="true",
The map visualization component automatically performs local data
"flattening" with geodetic data if the data window is less than
3 decimal degrees. Specifically, the map visualization component performs a
simple
mathematical transformation of the coordinates using a tangential
plane at the current map request center.
If allow_local_adjustment="false" (default), no adjustment is
performed.
- Automatically applies a globular map projection (geodetic data only):
If use_globular_projection="true", The map visualization component will
apply a globular projection on the fly to geometries being displayed.
If use_globular_projection="false" (the default), The map visualization
component does no map
projection to geodetic geometries. This option has no effect on
non-geodetic data.
-->
<!-<global_map_config>
<note text="Copyright 2009, Oracle Corporation"
font="sans serif"
position="SOUTH_EAST"/>
<title text="MapViewer Demo"
font="Serif"
position="NORTH" />
<logo image_path="C:\\images\\a.gif"
position="SOUTH_WEST" />
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<rendering allow_local_adjustment="false"
use_globular_projection="false" />
</global_map_config>
-->
<!-<!-<!-<!--
****************************************************************** -->
****************** Spatial Data Cache Setting ******************* -->
****************************************************************** -->
Uncomment and modify the following to customize the spatial data cache
used by the map visualization component. The default is 64 MB for in-memory
cache.
To disable the cache, set max_cache_size to 0.
max_cache_size: Maximum size of in-memory spatial cache of the map
visualization component.
Size must be specified in megabytes (MB).
report_stats:
If you would like to see periodic output of cache
statistics, set this attribute to true. The default
is false.
-->
<!-<spatial_data_cache
max_cache_size="64"
report_stats="false"
/>
-->
<!-- ****************************************************************** -->
<!-- ****************** Custom WMS Capabilities Info ****************** -->
<!-- ****************************************************************** -->
<!-- Uncomment and modify the following tag if you want the map visualization
component to
use the following information in its getCapabilities response.
Note: all attributes and elements of <wms_config> are optional.
-->
<!-<wms_config host="www.my_corp.com" port="80">
<title>
WMS 1.1 interface for Oracle Map visualization component
</title>
<abstract>
This WMS service is provided through the map visualization component.
</abstract>
<keyword_list>
<keyword>bird</keyword>
<keyword>roadrunner</keyword>
<keyword>ambush</keyword>
</keyword_list>
<sdo_epsg_mapfile>
../config/epsg_srids.properties
</sdo_epsg_mapfile>
</wms_config>
-->
<!-<!-<!-<!--
****************************************************************** -->
**************** Custom Non-Spatial Data Provider **************** -->
****************************************************************** -->
Uncomment and add as many custom non-spatial data provider as
needed here, each in its own <ns_data_provider> element.
You must provide the id and full class name here. Optionally you
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can also specify any number of global parameters, which the map visualization
component
will pass to the data provider implementation during initialization.
The name and value of each parameter is interpreted only by the
implementation.
-->
<!-- this is the default data provider that comes with the map visualization
component;
refer to the documentation on how to use it.
<ns_data_provider
id="defaultNSDP"
class="oracle.sdovis.NSDataProviderDefault"
/>
-->
<!-- this is a sample NS data provider with prameters:
<ns_data_provider
id="myProvider1" class="com.mycorp.bi.NSDataProviderImpl" >
<parameters>
<parameter name="myparam1" value="value1" />
<parameter name="p2"
value="v2"
/>
</parameters>
</ns_data_provider>
-->
<!-<!-<!-<!--
****************************************************************** -->
******************* Map Tile Server Setting ******************* -->
****************************************************************** -->
Uncomment and modify the following to customize the map tile server.
<tile_storage> specifies the default root directory under which the
cached tile images are to be stored if the cache instance configuration
does not specify the root directory for the cache instance. If the
default root directory is not set or not valid, the default root
direcotry will be set to be $MAPVIEWER_HOME/web/tilecache
default_root_path: The default root directory under which the cached
tile images are stored.
-->
<!-<map_tile_server>
<tile_storage default_root_path="/scratch/tilecachetest/"/>
</map_tile_server>
-->
<!-<!-<!-<!--
****************************************************************** -->
******************** Predefined Data Sources ******************** -->
****************************************************************** -->
Uncomment and modify the following to predefine one or more data
sources.
Note: You must precede the jdbc_password value with a '!'
(exclamation point), so that when the map visualization component
starts the next
time, it will encrypt and replace the clear text password.
-->
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<!-<map_data_source name="mvdemo"
jdbc_host="elocation.example.com"
jdbc_sid="orcl"
jdbc_port="1521"
jdbc_user="scott"
jdbc_password="!password"
jdbc_mode="thin"
number_of_mappers="3"
/>
-->
</MapperConfig>
This map visualization component configuration topic includes the following subtopics:
•
Specifying Logging Information
•
Specifying Map File Storage and Life Cycle Information
•
Specifying a Web Proxy
•
Specifying Global Map Configuration Options
•
Customizing the Spatial Data Cache
•
Specifying the Security Configuration
•
Registering a Custom Spatial Provider
•
Registering Custom Nonspatial Data Providers
•
Customizing SRS Mapping
•
Customizing WMS GetCapabilities Responses
•
Customizing WMTS GetCapabilities Responses
•
Configuring the Map Tile Server for Oracle Maps
•
Defining Permanent Map Data Sources
•
Configuring and Securing the Map Data Server for the HTML5 API
•
Specifying Logging Information
•
Specifying Map File Storage and Life Cycle Information
•
Specifying a Web Proxy
•
Specifying Global Map Configuration Options
•
Customizing the Spatial Data Cache
•
Specifying the Security Configuration
•
Registering a Custom Spatial Provider
•
Registering Custom Nonspatial Data Providers
•
Customizing SRS Mapping
•
Customizing WMS GetCapabilities Responses
•
Customizing WMTS GetCapabilities Responses
•
Configuring the Map Tile Server for Oracle Maps
•
Defining Permanent Map Data Sources
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Configuring and Securing the Map Data Server for the HTML5 API
1.5.2.1 Specifying Logging Information
The map visualization component provides a flexible logging mechanism to record
runtime information and events. You can configure the granularity, volume, format, and
destination of the log output. You can also configure the maximum size of log files as
well as automatic log file rotation.
There are two ways to configure the map visualization component's logging: containercontrolled logging, and using the <logging> element in the configuration file.
Container-Controlled Logging
If the <logging> element in the mapViewerConfig.xml file is commented out or missing,
the map visualization component uses container-controlled logging, specifically using
the following loggers:
•
oracle.mapviewer.ws for all web server (maps, tiles, features) messages
•
oracle.mapviewer.access for all user access
•
oracle.mapviewer.sdovis for all rendering (maps, themes, features) messages
•
oracle.mapviewer.webconsole for all administrative console log messages
Using the <logging> Element
If the <logging> element in the mapViewerConfig.xml file is in use (that is, if the <logging>
element is not commented out or missing), The map visualization component uses that
information instead of using container-controlled logging. The <logging> element can
have the following attributes and subelements:
•
The console_log_level attribute controls the levels of information that are recorded
in the log, which in turn affect the log output volume. Set the console_log_level
attribute value to one of the following, listed from most restrictive logging to least
restrictive logging: FATAL, ERROR, WARN, INFO, DEBUG, and FINEST. The FATAL level
outputs the least log information (only unrecoverable events are logged), and the
other levels are progressively more inclusive, with the FINEST level causing the
most information to be logged. For production work, a level of WARN or more
restrictive (ERROR or FATAL) is recommended; however, for debugging you may want
to set a less restrictive level.
•
The file_limit attribute controls the maximum file size of a log file. The unit is Mb
and the default value is 50 (that is, by the default value for the maximum log file
size is 50Mb).
•
The file_count attribute determines the number of log files created. The files are
rotated (that is, when the last log file reaches its maximum size, the first log file is
reused). The default value is 10.
•
The <logger> subelement specifies the log level for a particular logger.
•
The <log_output> subelement identifies output for the logging information. By
default, log records are written to the system error console. You can change this to
the system output console or to one or more files, or some combination. If you
specify more than one device through multiple <log_output> subelements, the
logging records are sent to all devices, using the same logging level and attributes.
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1.5.2.2 Specifying Map File Storage and Life Cycle Information
Map image file information is specified in the <save_images_at> element. By default,
images are stored in the $ORACLE_HOME /lbs/mapviewer/web/images directory. You do not
need to modify the <save_images_at> element unless you want to specify a different
directory for storing images.
A mapping client can request that the map visualization component send back the
URL for an image file instead of the actual map image data, by setting the format
attribute of the <map_request> element to GIF_URL or PNG_URL. In this case, the map
visualization component saves the requested map image as a file on the host system
where the map visualization component is running and sends a response containing
the URL of the image file back to the map client.
You can specify the following map image file information as attributes of the
<save_images_at> element:
•
The file_prefix attribute identifies the map image file prefix. A map image file
name will be a fixed file prefix followed by a serial number and the image type
suffix. For example, if the map image file prefix is omsmap, a possible GIF map
image file could be omsmap1.gif.
Default value: file_prefix=omsmap
•
The url attribute identifies the map image base URL, which points to the directory
under which all map image files are saved on the map visualization component
host. The map image URL sent to the mapping client is the map image base URL
plus the map image file name. For example, if the map image base URL is http://
dev04.example.com:1521/mapviewer/images, the map image URL for omsmap1.gif will
be http://dev04.example.com:1521/mapviewer/images/omsmap1.gif.
Default value: url=$HOST_URL/mapviewer/images
•
The path attribute identifies the path of the directory where all map image files are
saved on the map visualization component host system. This directory must be
accessible by HTTP and must match the map image URL. Map image files saved
in the directory specified by the path attribute should be accessible from the URL
specified by the url attribute.
However, if you are deploying the map visualization component to WebLogic
Server, the default value for the path attribute (../web/images) is not correct. The
path attribute value in this case should be ../../images, because the physical
"images" directory is mapviewer.ear/web.war/images; so using relative path, the
value should be ../../images for the path attribute to resolve to the physical
directory.
•
The life attribute specifies the number of minutes that a generated map image is
guaranteed to stay on the file system before the image is deleted. If the life
attribute is specified, the recycle_interval attribute controls how frequently the
map visualization component checks for possible files to delete.
Default: The map visualization component never deletes the generated map
images.
•
The recycle_interval attribute specifies the number of minutes between times
when the map visualization component checks to see if it can delete any image
files that have been on the file system longer than the number of minutes for the
life attribute value.
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Default value: 480 (8 hours)
1.5.2.3 Specifying a Web Proxy
Sometimes the map visualization component server needs to make HTTP connections
to external web servers, such as to obtain a background image through a URL or to
contact an external WMS server to fetch its map images. In such cases, if there is a
firewall between the map visualization component server and the target web server,
you may need to specify the HTTP proxy information to the map visualization
component so that it will not be blocked by the firewall. The following example
specifies web proxy information:
<web_proxy host="www-proxy.mycorp.com" port="80" />
If the web proxy requires authentication, you can specify the user and password
attributes. If the password value is preceded by the exclamation mark (!) character,
the password value will be encrypted on the first loading of the configuration file. For
example:
<web_proxy host="www-proxy.mycorp.com" port="80" user="uservalue" password="!
pwdvalue" />
1.5.2.4 Specifying Global Map Configuration Options
You can specify the following global "look and feel" options for the display of each map
generated by the map visualization component:
•
Title
•
Note (such as a copyright statement or a footnote)
•
Logo (custom symbol or corporate logo)
•
Local geodetic data adjustment
•
Splitting geometries along the 180 meridian
To specify any of these options, use the <global_map_config> element. For example:
<global_map_config>
<note text="Copyright (c) 2009, Example Corporation"
font="sans serif"
position="SOUTH_EAST"/>
<title text="Map Courtesy of Example Corp."
font="Serif"
position="NORTH"/>
<logo image_path="C:\\images\\a.gif"
position="SOUTH_WEST"/>
<rendering allow_local_adjustment="false"
use_globular_projection="false"/>
</global_map_config>
Set the map title through the <title> element of the <global_map_config> element. You
can also set the map title in an individual map request by specifying the title attribute
with the <map_request> element, and in this case, the title in the map request is used
instead of the global title in the map visualization component configuration file. Note
the following information about the attributes of the <title> element:
•
The text attribute specifies the title string.
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•
The font attribute specifies a font. The font must exist on the system where the
map visualization component is running.
•
The position attribute provides a positioning hint to the map visualization
component when determining where the map title will be drawn on a map.
Possible values are: NORTH, EAST, SOUTH, WEST, NORTH_EAST, SOUTH_EAST, SOUTH_WEST,
NORTH_WEST, and CENTER.
Default value: NORTH
Set the map note through the <note> element of the <global_map_config> element. Note
the following information about the attributes of the <note> element:
•
The text attribute specifies the note string.
•
The font attribute specifies a font. The font must exist on the system where the
map visualization component is running.
•
The position attribute provides a positioning hint to the map visualization
component when determining where the map note will be drawn on a map.
Possible values are: NORTH, EAST, SOUTH, WEST, NORTH_EAST, SOUTH_EAST, SOUTH_WEST,
NORTH_WEST, and CENTER.
Default value: SOUTH_EAST
Set the map logo through the <logo> element of the <global_map_config> element. The
map logo image must be in either JPEG or GIF format. The image can be stored in a
local file system where the map visualization component instance will have access to
it, or it can be obtained from the web by specifying its URL. To specify a map logo,
uncomment the <map_logo> element in the map visualization component configuration
file and edit its attributes as needed.
Note the following information about the attributes of the <logo> element:
•
The image_path attribute must specify a valid file path name, or a URL starting with
http://.
•
The position attribute provides a positioning hint to the map visualization
component when determining where the map logo will be drawn on a map.
Possible values are: NORTH, EAST, SOUTH, WEST, NORTH_EAST, SOUTH_EAST, SOUTH_WEST,
NORTH_WEST, and CENTER.
Default value: SOUTH_WEST
If the logo image is obtained through a URL that is outside your firewall, you may need
to set the web proxy in order for the map visualization component to retrieve the logo
image. For information about specifying a web proxy, see Specifying a Web Proxy.
If you also specify a map legend, be sure that its position is not the same as any
position for a map title, note, or logo. (Map legends are explained in Map Legend. The
default position for a map legend is SOUTH_WEST.)
To have the map visualization component automatically project geodetic data to a
local non-geodetic coordinate system before displaying it if the map data window is
less than 3 decimal degrees, specify allow_local_adjustment="true" in the <rendering>
element.
To have the map visualization component automatically apply a globular map
projection (that is, a map projection suitable for viewing the world, and specifically the
azimuthal equidistant projection for the map visualization component), specify
use_globular_projection="true" in the <rendering> element. This option applies to
geodetic data only.
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1.5.2.5 Customizing the Spatial Data Cache
You can customize the in-memory cache that the map visualization component uses
for spatial data by using the <spatial_data_cache> element. For example:
<spatial_data_cache
max_cache_size="64"
report_stats="true"
/>
You can specify the following information as attributes of the <spatial_data_cache>
element:
•
The max_cache_size attribute specifies the maximum number of megabytes (MB) of
in-memory cache.
Default value: 64
•
The report_stats attribute, if set to true, instructs the map visualization component
server to periodically (every 5 minutes) output cache statistics, such as the
number of objects cached, the total size of cache objects, and data relating to the
efficiency of the internal cache structure. The statistics are provided for each data
source and for each predefined theme. They can help you to determine the
optimal setting of the in-memory cache. For example, if you want to pin all
geometry data for certain themes in the memory cache, you need to specify a
max_cache_size value that is large enough to accommodate these themes.
Default value: false
The spatial data cache is always enabled by default, even if the element is commented
out in the configuration file. To completely disable the caching of spatial data, you
must specify the max_cache_size attribute value as 0 (zero).
Note:
The disk-based spatial cache, which was supported in the previous release, is
no longer supported, because performance tests have shown that disk-based
spatial caching was often less efficient than fetching spatial objects directly
from the database when needed (that is, in cases where the cached objects
frequently did not need to be retrieved again after caching).
For detailed information about the caching of predefined themes, see Caching of
Predefined Themes.
1.5.2.6 Specifying the Security Configuration
You can use the <security_config> element to specify whether the map visualization
component should reject <info_request> elements in requests. An <info_request>
element is a type of request from a client that asks the map visualization component to
execute a simple SQL statement and return the result rows in plain text or XML format.
This request is often used by the map visualization component applications to identify
features displayed on a map, or to run simple spatial search queries.
However, if the map visualization component data source information is exposed,
malicious attackers might be able to abuse this capability and obtain sensitive
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information. To prevent this from happening, you can make sure the map visualization
component always connects to a database schema that has very limited access rights
and hosts only non-sensitive information, and you can also reject all <info_request>
requests by specifying the <security_config> element as follows:
<security_config>
<disable_direct_info_request> true </disable_direct_info_request>
</security_config>
Note, however, that this setting affects some map visualization component features.
For example, the identify() method of the map visualization component Java API will
no longer work, and applications will need to implement their own identify() method
through other means.
You can also define remote URLs that the map visualization component built-in proxy
servlet is allowed to communicate with. Use commas to separate such URLs. You can
end a URL with the * (asterisk) wildcard character to allow multiple URLs that start with
a path. The following example specifies one remote URL:
<security-config>
…
<proxy_enabled_hosts>
foo.com:8080/mapviewer
</proxy_enabled_hosts>
…
</security-config>
To facilitate the map visualization component's HTTPS (SSL) connection with external
web sites that use self-signed certificates, you may register those certificates here.
Use one entry for each server that requires an HTTPS connection. The following
example shows an excerpt specifying one entry:
<security_config>
…
<certificates>
<entry>
<host_name>fooserver.com</host_name>
<keystore_file>/scratch/fooserver.jks</keystore_file>
<key>123456</key>
</entry>
</certificates>
…
</security_config>
The subelements for each certificate's <entry> element are the following.
The host_name attribute specifies the IP address or domain name of the server that
requires an HTTPS connection.
The keystore_file attribute specifies the file containing a single self-signed certificate.
After you obtain the certificate (typically a .pem file) from the server site, you can create
a key store by using the Java keytool command. For example:
keytool -import -file fooserver.pem -alias fooserver -keystore fooserver.jks
The key attribute specifies the password that you provided when creating the key store
file. (It is used to ensure the integrity of the key store file itself.)
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1.5.2.7 Registering a Custom Spatial Provider
The map visualization component can render spatial data that is in an external (nonOracle Spatial and Graph) native format, such as shapefile, if there is a spatial
provider implementation registered for the format. For information about implementing
an external spatial data provider (in connection with custom geometry themes), see
Custom Geometry Themes.
To register an external spatial data provider, use the <s_data_provider> element, as
shown in the following example:
<s_data_provider
id="shapefileSDP"
class="oracle.sdovis.ShapefileDataProvider"
>
<parameters>
<parameter name="datadir" value="/temp/data" />
</parameters>
</s_data_provider>
The class attribute specifies the name of the class that implements the external spatial
data provider.
The <parameters> element specifies a set of initialization parameters that are used by
the data provider during its initialization process. In this example, the shapefile
provider has a data directory ("datadir") parameter that points to directory where the
map visualization component can look for the data.
1.5.2.8 Registering Custom Nonspatial Data Providers
When generating thematic map layers, the map visualization component can
dynamically join nonspatial attribute data (such as sales for each region) that
originates from an external source with the base geometries (boundaries of all the
regions) that are stored in the database. For information about thematic mapping using
external attribute data from nonspatial data providers, see Thematic Mapping Using
External Attribute Data.
To register a nonspatial data provider, use the <ns_data_provider> element, as shown
in the following example:
<ns_data_provider id="testProvider"
class="com.mycorp.GetSalesData" >
<parameters>
<parameter name="bi_database" value="stadb32.mycorp.com" />
<parameter name="sid" value="bidata" />
</parameters>
</ns_data_provider>
The id attribute uniquely identifies a nonspatial data provider. Use this id value in any
map request that involves the provider.
The class attribute specifies the name of the class that implements the nonspatial data
provider.
The <parameters> element specifies a set of initialization parameters that are used by
the nonspatial data provider during its initialization process.
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1.5.2.9 Customizing SRS Mapping
You can use the <srs_mapping> element to specify an SDO to EPSG SRID mapping
file, which define mappings between Oracle Spatial and Graph SDO_SRID values and
EPSG codes. As explained in SDO to EPSG SRID Mapping File, each line in the
specified mapping file must contain an SDO_SRID value and the corresponding EPSG
code. The <srs_mapping> element can be used with WMS and WFS themes.
The following example uses the <srs_mapping> element to specify an SDO to EPSG
SRID mapping file:
<srs_mapping>
<sdo_epsg_mapfile>
../config/epsg_srids.properties
</sdo_epsg_mapfile>
</srs_mapping>
1.5.2.10 Customizing WMS GetCapabilities Responses
The map visualization component can be used as an Open Geospatial Consortium
WMS (Web Map Server) 1.1.1 compliant server. As such, a WMS client can send the
map visualization component the GetCapabilities request. In response, the map
visualization component will send back the list of themes that it hosts and other
important information, such as the data provider's name and a list of keywords that
might of interest to the requesting client.
Note:
There is a separate WMS configuration file (wmsConfig.xml) that contains more
information than is in the <wms_config> element in the map visualization
component configuration file. It is recommended that you define any custom
WMS configuration parameters in this separate WMS configuration file; any
settings there will override any conflicting settings in the <wms_config> element
in the map visualization component configuration file.
For more information about the wmsXonfig.xml file, see Customizing
GetCapabilities Responses: Additional Options.
You can use the <wms_config> element to customize the descriptive information sent
back to the client as part of the GetCapabilities response, as shown in the following
example:
<wms_config host="www.my_corp.com" port="80"
protocol="http" default_datasource="dsrc1"
public_datasources="dsrc1,dsrc2">
<title>
WMS 1.1 interface for Oracle Application Server 10g MapViewer
</title>
<abstract>
This WMS service is provided through Oracle MapViewer.
</abstract>
<keyword_list>
<keyword>bird</keyword>
<keyword>roadrunner</keyword>
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<keyword>ambush</keyword>
</keyword_list>
<sdo_epsg_mapfile>
../config/epsg_srids.properties
</sdo_epsg_mapfile>
</wms_config>
The host attribute specifies the host part of the service request URL that the client
should use for future WMS requests made to this map visualization component server.
The port attribute specifies the port part of the service request URL that the client
should use for future WMS requests made to this map visualization component server.
The protocol attribute specifies the protocol part of the service request URL that the
client should use for future WMS requests made to this map visualization component
server.
The default_datasource attribute specifies the base data source used to retrieve the
capabilities response. If this attribute is not defined, the data source WMS is used, and
that data source must exist in this map visualization component server.
The public_datasources attribute specifies which data source contents are to be listed
in the GetCapabilities response. If this attribute is not defined, all data source contents
will be listed.
The <title> element specifies the service title to be included as part of the response.
The <abstract> element specifies the abstract to be included as part of the response.
The <keyword_list> element specifies a list of keywords that best describe the types of
layers served by this map visualization component server.
The <sdo_epsg_mapfile> element specifies a text file that defines mappings from Oracle
Spatial and Graph (SDO) SRID values to the corresponding EPSG SRID values that
are typically used in most WMS requests and responses. For information about this
mapping file, see SDO to EPSG SRID Mapping File.
1.5.2.11 Customizing WMTS GetCapabilities Responses
The map visualization component can be used as an Open Geospatial Consortium
WMTS (Web Map Tile Service) 1.0.0 compliant server, enabling tile layers defined in
the USER_SDO_CACHED_MAPS metadata view to be retrieved through WMTS
requests. A WMTS client can send to the map visualization component the
GetCapabilities request. In response, the map visualization component will send back
the list of tile layers that it hosts and other important information, such as the data
provider's name and a list of keywords that might of interest to the requesting client.
You can edit the WMTS configuration file, which is stored in the same folder as that for
mapViewerConfig.xml with a name of wmtsConfig.xml, to provide such customized
information.
In the wmtsConfig.xml file, you can use the <wmts_config> element to customize the
descriptive information sent back to the client as part of the GetCapabilities response,
as shown in the following example:
<wmts_config>
<public_datasources>
<public_datasource name="MVDEMO" include_all_tile_layers="true"/>
<public_datasource name="ELOCATION">
<tile_layers>
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<tile_layer name="WORLD_MAP"/>
</tile_layers>
</public_datasource>
</public_datasources>
<sdo_epsg_mapfile>
../config/epsg_srid.properties
</sdo_epsg_mapfile>
<ServiceAttributes>
<ServiceIdentification>
<Title>Web Map Tile Service by myCorp</Title>
<Abstract> U.S. maps for state and county boundaries and big cities</
Abstract>
<Keywords>
<Keyword>Maps,U.S. State Boundaries,Cities</Keyword>
</Keywords>
</ServiceIdentification>
<ServiceProvider>
<ProviderName>provider's name</ProviderName>
<ProviderSite url="http://www.myCorp.com/mySite"/>
</ServiceProvider>
</ServiceAttributes>
</wmts_config>
The <public_datasources> element can contain <public_datasource> subelements,
which specify which data sources' tile layers to list in the WMTS GetCapabilities
response. If this <public_datasources> element is not defined, all data sources' tile
layers will be listed; if this element is defined but contains no <public_datasource>
subelement, then no tile layers from any data source will be listed in the response.
The <public_datasource> element must contain a name attribute, which indicates the
name of the data source.
The include_all_tile_layers attribute is optional, and the default is false. When set to
true, it indicates that all tile layers in that data source are to be listed in the response.
The <tile_layer> element must contain a name attribute, which indicates the name of
the tile layer to be included in the response from the data source defined in its parent
element.
The <sdo_epsg_mapfile> element specifies a text file that defines mappings from Oracle
Spatial and Graph (SDO) SRID values to the corresponding EPSG SRID values that
are typically used in most WMTS requests and responses. For information about this
mapping file, see SDO to EPSG SRID Mapping File.
The <Title> element specifies the service title to be included as part of the response.
The <Abstract> element specifies the abstract to be included as part of the response.
The <Keywords> element specifies a collection of keywords (from its <Keyword>
subelements) that best describe the types of layers served by this map visualization
component server.
More information can be found in the comments in the wmtsConfig.xml file.
1.5.2.12 Configuring the Map Tile Server for Oracle Maps
The Oracle Maps feature of the map visualization component can pre-generate base
map image tiles and cache them through the map tile server. You can use the
<map_tile_server> element to provide configuration information to the map tile server,
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such as default location for map tile file storage, and logging information, as shown in
the following example:
<map_tile_server>
<tile_storage default_root_path="/scratch/tilecache/" />
<logging log_level="finest" log_thread_name="false" log_time="true">
<log_output name="System.err"/>
</logging>
</map_tile_server>
The <tile_storage> element specifies the default root directory where all map image
tiles generated by this map visualization component server will be stored.
The <logging> element specifies logging information specific to the map tile server.
1.5.2.13 Defining Permanent Map Data Sources
Every map request must have a data source attribute that specifies a map data
source, which is a database user with geospatial data. You can predefine available
map data sources by using the <map_data_source> element. For example:
<map_data_source name="mvdemo"
jdbc_host="mapsrus.example.com"
jdbc_sid="orcl"
jdbc_port="1521"
jdbc_user="scott"
jdbc_password="!password"
jdbc_mode="thin"
number_of_mappers="5"
allow_jdbc_theme_based_foi="true"
plsql_package="web_user_info"
/>
You can specify the following information as attributes of the <map_data_source>
element:
•
The name attribute specifies a unique data source name to the map visualization
component. You must specify the data source name in all map requests that
identify a data source.
•
You must specify all necessary connection information, or a container data source
name, or a net service name (TNS name). That is, you must specify only one of
the following, which are described in this section: jdbc_host, jdbc_sid, jdbc_port,
and jdbc_user; or container_ds; or jdbc_tns_name.
If the database on which you defined a data source on is restarted, and if the data
source is created from jdbc_host/jdbc_sid/jdbc_port or jdbc_tns_name attributes,
The map visualization component will resume normal operation (for example
responding to map requests with properly created maps) as soon as the database
is back online.
•
The jdbc_host, jdbc_sid, jdbc_port, and jdbc_user attributes specify the database
connection information and the database user name. (As an alternative to
specifying these attributes and the jdbc_password and jdbc_mode attributes, you can
specify the container_ds attribute, described later in this section.)
•
The jdbc_password attribute specifies the database user's login password. It must
be prefixed with an exclamation point (!) when you specify the password for the
first time. When the map visualization component next restarts, it will automatically
obfuscate and replace the clear text password.
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The map visualization component does not change this password string in any
way; no conversion to upper or lower case is performed. If the database uses
case-sensitive passwords, the specified password must exactly match the
password in the database.
•
The jdbc_mode attribute tells the map visualization component which Oracle JDBC
driver to use when connecting to the database. The default is thin (for the "thin"
driver). The other possible value is oci8, which requires that you also have the
Oracle Database client installed on the same host on which the map visualization
component is running.
•
The container_ds attribute lets you specify the Java EE container name (JNDI
name) instead of specifying the jdbc_host, jdbc_sid, jdbc_port, jdbc_user,
jdbc_password, and jdbc_mode attributes. For example, assume you created a JDBC
data source and gave it a JNDI name of jdbc/OracleDS. You can then define the
permanent map visualization component data source as follows:
<map_data_source name="mvdemo"
container_ds="jdbc/OracleDS"
number_of_mappers="5"
/>
If you use the container_ds attribute, and if you want the map visualization
component to resume normal operation (for example, responding to map requests
with properly created maps) automatically after the database on which you defined
a data source is restarted, you must instruct the container data source to always
validate a connection before it can be returned to the application.
•
The jdbc_tns_name attribute identifies a net service name that is defined in the
tnsnames.ora file.
•
The number_of_mappers attribute identifies the maximum number of map renderers
available (and thus the maximum number of map requests that the map
visualization component can process in parallel for the data source) for this data
source. Any unprocessed map requests are queued and eventually processed.
For example, if the value is 3, the map visualization component will be able to
process at most three mapping requests concurrently. If a fourth map request
comes while three requests are being processed, it will wait until the map
visualization component has finished processing one of the current requests.
Specifying a large number_of_mappers value (such as 50 or 100) can improve the
overall throughput, but it will also increase runtime memory and CPU usage at
times of peak loads, since the map visualization component will attempt to process
more concurrent map requests. It will also increase the number of active database
sessions. Therefore, be sure that you do not set too large a number for this
attribute.
Note:
The obsolete max_connections attribute no longer affects rendering and is
ignored. The number_of_mappers attribute value affects the actual maximum
number of database connections or sessions open for the data source at any
given time.
•
The allow_jdbc_theme_based_foi attribute lets you specify whether to allow JDBC
theme-based FOI requests to be performed against this data source. A JDBC
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theme-based FOI request is based on a dynamic SQL query constructed by the
JavaScript client application.
By default, such FOI requests are not allowed unless you set this attribute to true.
Due to the potential security threat, JDBC theme-based FOI requests should be
used with caution. You should only allow JDBC theme-based FOI requests on
database connections that are granted very low privilege and contain only data
that you want to expose.
•
The plsql_package attribute lets you specify a PL/SQL package to be used for
secure map rendering, as explained in Secure Map Rendering.
•
The web_user_type attribute (not shown in the example in this section) lets you
specify the source for the authenticated user's name. It is especially useful for
getting the authenticated user's name from a cookie, in conjunction with specifying
a PL/SQL package to be used for secure map rendering. For more information
about the web_user_type attribute and an example of its use, see Getting the User
Name from a Cookie.
1.5.2.14 Configuring and Securing the Map Data Server for the HTML5 API
Themes can be streamed by default, and the only way to protect them is by adding
authentication, that is, by adding a security constraint in the map visualization
component web.xml file and by configuring the <mds_config> element in the
configuration file to authorize access to various themes.
The Map Data Server (MDS) server component facilitates the streaming of geospatial
data in vector format to the Oracle Maps API (described in Oracle Maps JavaScript
API). The MDS provides a RESTful API for browser clients to request the vector data
of any predefined or dynamic (JDBC) theme from a map visualization component
server instance. The only way to secure or protect the access to this service is by
adding a security constraint in the map visualization component web.xml deployment
file, as in the following example:
<security-constraint>
<web-resource-collection>
. . .
<url-pattern>/dataserver/*</url-pattern>
</web-resource-collection>
<auth-constraint>
<role-name>map_admin_role</role-name>
</auth-constraint>
</security-constraint>
The preceding example adds a security constraint to any incoming URL with the
relative path /dataserver/ in it. Because the MDS servlet responds only to URLs with /
dataserver in its path, this constraint effectively protects all access to the MDS. This
means that any application or web client accessing the Map Data Server will require
proper authentication, and only those users with the role map_admin_role will be granted
access. (For more information on how to secure a Java EE servlet such as MDS,
check the Java EE and WebLogic Server documentation.)
Access to any predefined or dynamic (JDBC) theme's vector data is blocked by
default, regardless of whether you added a security constraint on the MDS URL
patterns. In other words, for example, even if the /dataserver/* URLs are protected
and an HTML5 application has passed authentication, it still cannot access a theme's
data without proper authorization. When an Oracle Maps HTML5 application attempts
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to load or display a theme without proper authorization, the error message typically
contains a statement like "This data source does not allow streaming access."
To grant access to a data source's themes, you must explicitly configure the
<mds_config> element in the configuration file.
Example 1-2
Configuring the mds.xml File
Example 1-2 shows an <mds_config> element in which two map visualization
component data sources, mvdemo and my-data, are configured such that certain themes
of theirs can be streamed to clients.
<mds_config>
<data_source name="mvdemo">
<allow_predefined_themes>true</allow_predefined_themes>
<deny>my_secret_theme</deny>
<allow_dynamic_themes>true</allow_dynamic_themes>
</data_source>
<data_source name="my-data">
<allow_predefined_themes>false</allow_predefined_themes>
<allow>
<theme>public_points_theme</theme>
<theme>office_locations*</theme>
</allow>
<allow_dynamic_themes>false</allow_dynamic_themes>
</data_source>
</mds_config>
In Example 1-2:
•
Each data source authorizes its themes in its own <data_source> element. With this
element, the two tags <allow_predefined_themes> and <allow_dynamic_themes>
provide the overall or default access control on these two types of themes. Note
that for dynamic/JDBC themes, you can also disable them in the data source
definition (in the main mapViewerConfig.xml file). If a dynamic theme is disabled in
the data source definition, then that setting always has precedence (regardless of
how it is set in the <mds_config> element.).
•
The mvdemo data source grants all clients with access to both predefined and
dynamic (JDBC) theme vector data by default; this is a reasonable choice given
the nature of the data (data from publicly available samples). An exception is
added, however, for the my_secret_theme theme, through the use of the <deny> tag.
•
For the my-data data source, access to both types of themes is blocked by default.
In this case exceptions (to open certain themes to streaming) are added through
the <allow> tag. In both <allow> and <deny> tags, the theme names or patterns are
case insensitive, and the wild card character * (asterisk) can be used to match
multiple themes. The example uses the <allow> tag to open the theme
public_points_theme and all the themes whose name starts with office_locations
to streaming, while all other themes are blocked. No dynamic/SQL theme is
allowed on this data source.
If you modify the <mds_config> element, you must restart the deployed map
visualization component instance for the modifications to take effect.
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1.5.3 Performing Map Visualizer Administrative Tasks
Besides knowing how to configure the map visualizer, you should also know how to
perform other important administrative tasks using the map visualizer administration
page. To log in to this page, see the instructions in Logging in to the Map Visualization
Component Administration Page.
The tasks you can do as a map visualizer administrator include the following:
•
Editing the configuration file
Click Configuration.
•
Refreshing the list of data sources
Click Admin to refresh the list automatically, or click Refresh to perform a manual
refresh.
•
Clearing cached definitions of map visualizer styles, themes, and base maps
Click Admin, select the data source, then click Purge Cached Metadata.
•
Clearing cached geometry data for predefined themes
Click Admin, then Geometry Cache, then Purge for a selected theme or all
themes.
•
Creating map tile layers for Oracle Maps
Click Admin, then Create Tile Layer, select the tile layer type, and click Next.
Internal map source: Enter the map cache name, then select the data source and
base map. Also define parameters for cache storage (where tiles will be stored),
zoom levels, minimum and maximum scale, spatial reference ID (SRID), data
bounding box (MBR), and tile size and format. Click Next and Submit to create
the map tile layer. You can also define the map cache properties in XML by
clicking XML.
External map source: Enter the map cache name, then select the data source. To
provide access to the external source, define parameters such as the map service
URL, the request method (GET or POST), the proxy information (if needed), the
java adapter class name and its location on the server, and additional adapter
properties. Also define parameters for cache storage (where tiles will be stored),
zoom levels, minimum and maximum scale, spatial reference ID (SRID), data
bounding box (MBR), and tile size and format. Click Next and Submit to create
the map tile layer. You can also define the map cache properties in XML by
clicking XML.
For other types of tile layers (Oracle Maps, Bing, Here, Google, TomTom), follow
similar steps.
•
Managing map tile layers for Oracle Maps
Click Admin, then Manage Tile Layers. Then do any of the following:
To manually refresh the tile layer list, click Refresh.
To edit a map tile layer, select the row for that layer and click Edit/View Details.
To view and manage map tile layer, select the row for that layer and click View
Map/Manage Tiles.
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1.6 Oracle Real Application Clusters and the Map Visualizer
When the database is an Oracle Real Application Cluster (Oracle RAC), you can
connect to the Oracle RAC database using either of the following options.
•
Let the map visualizer connect to the database through the data source of the
Java EE container, such as WebLogic Server 12c.
Create a JDBC data source that connects to the Oracle RAC database, as
explained in Creating a Container Oracle RAC Data Source for the Map Visualizer
Server. The data source can then be used by the map visualizer and other
applications through JNDI lookup.
This option is often used at sites where administrators create and monitor these
kinds of connections, and/or where connections are used by multiple applications.
This option also hides the database connection details (such as database user
name and password) from the applications.
•
Enable the map visualizer to connect to the database service directly.
Define a map visualizer data source directly using the Oracle RAC service name
(not the database SID), as explained in Creating a Map Visualizer Data Source
Using the Oracle RAC Service Name.
This option is simpler to implement than the preceding option.
After doing either of the these options, restart the map visualizer, as explained in
Restarting the Map Visualizer.
•
Creating a Container Oracle RAC Data Source for the Map Visualizer Server
•
Creating a Map Visualizer Data Source Using the Oracle RAC Service Name
•
Restarting the Map Visualizer
1.6.1 Creating a Container Oracle RAC Data Source for the Map
Visualizer Server
You can create a JDBC data source in the map visualizer container for Oracle RAC,
and then use that container data source in the map visualizer configuration file, as
follows:
1.
Create a Container Oracle RAC Data Source.
2.
Create a Map Visualizer Data Source Using a Container Data Source.
•
Create a Container Oracle RAC Data Source
•
Create a Map Visualizer Data Source Using a Container Data Source
1.6.1.1 Create a Container Oracle RAC Data Source
You can use Oracle Enterprise Manager 12c or later to create a data source that
connects to the Oracle RAC database.
The following steps show how to create GridLink data source. (These are followed by
steps showing how to create a Multi data source.)
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1.
Log in to Enterprise Manager and in the Target Navigation pane, click the server
instance that contains the map visualizer server.
In Figure 1-2, clicking map_viewer1 under WebLogic Domain causes the
map_viewer1 server information to appear in the main area of the window.
Figure 1-2
Selecting the Server Instance
2.
Figure 1-3
Click WebLogic Server and select JDBC Data Sources, as shown in Figure 1-3.
Displaying JDBC Data Sources
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3.
Figure 1-4
Under JDBC Data Sources, click Create and select GridLink Data Source, as
shown in Figure 1-4.
Creating a GridLink Data Source
4.
Enter any necessary information in the Creating New JDBC Data Source wizard.
For example, to create a container data source named jdbc/mvdemo:
a.
Data Source Properties: Specify Data Source Name as mvdemo, Driver
Service Name as Oracle Driver (Thin XA) for GridLink Connections
Versions: Any, and JNDI Name as jdbc/mvdemo.
b.
Connection Properties: Generate the URL for database user mvdemo on the
appropriate host.
c.
Transaction Properties: Accept the displayed transaction properties.
d.
ONS Properties: Accept the displayed transaction properties, or make any
changes as needed.
e.
Select Targets: Select (check) map_viewer1 under Name to deploy the JDBC
data source on the desired server.
f.
Review: Review the properties for the new data source to be created. If you
need to make any changes, go back and make them and then return to this
page.
To create a Multi data source instead of a GridLink data source as in the preceding
instructions, adapt the steps as appropriate. For example:
1.
Log in to Enterprise Manager and in the Target Navigation pane, click the server
instance that contains the map visualizer server.
In Figure 1-5, clicking map_viewer1 under WebLogic Domain causes the
map_viewer1 server information to appear in the main area of the window.
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Figure 1-5
Selecting the Server Instance
2.
Figure 1-6
Click WebLogic Server and select JDBC Data Sources, as shown in Figure 1-6.
Displaying JDBC Data Sources
3.
Under JDBC Data Sources, click Create and select Multi Data Source, as shown
in Figure 1-7.
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Figure 1-7
Creating a Multi Data Source
4.
Enter any necessary information. For example:
a.
Data Source Properties: Specify Data Source Name as mvdemo, JNDI Name
as jdbc/mvdemo, and Algorithm Type as Failover.
b.
Select Targets: Select (check) map_viewer1 under Name .
c.
Select Data Source Type: Accept the default values (non-XA Driver).
d.
Click Create New Data Source.
e.
Specify properties for the first data source node, such as: Name: mvdemo-rac0,
JNDI Name: jdbc/mvdemo-rac0, Database Type: Oracle.
f.
For Database Driver, select Oracle's Driver (Thin) for Oracle RAC ServiceInstance connections: Versions: Any.
g.
Accept the default values (Supports Global Transactions and One-Phase
Commit).
h.
Define the connection properties for Node 1. Provide values for Service Name,
Database Name, Host Name, Port, Database User Name, Password, and
Protocol.
i.
Verify the properties and click Test Configuration. If it succeeds, click Next.
j.
Select (check) the server in which the map visualizer is deployed
(map_viewer1), and click Finish.
k.
On the next page, click Create a New Data Source to create and configure
the second node.
l.
Specify properties for the second data source node, such as: Name: mvdemorac1, JNDI Name: jdbc/mvdemo-rac1, Database Type: Oracle.
m. For Database Driver, select Oracle's Driver (Thin) for Oracle RAC ServiceInstance connections: Versions: Any.
n.
Accept the default values (Supports Global Transactions and One-Phase
Commit).
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o.
Define the connection properties for Node 2. Provide values for Service Name,
Database Name, Host Name, Port, Database User Name, Password, and
Protocol.
p.
Verify the properties and click Test Configuration. If it succeeds, click Next.
q.
Select (check) the server in which the map visualizer is deployed
(map_viewer1), and click Finish.
r.
If you need to add more nodes, click Create a New Data Source and create
each in the same way as before.
1.6.1.2 Create a Map Visualizer Data Source Using a Container Data Source
After creating a container data source in the map visualizer container (explained in
Create a Container Oracle RAC Data Source), create a new map visualizer data
source that enables it to connect to the Oracle RAC database by adding the
container_ds attribute in the map visualizer data source. For example:
<map_data_source name="mvdemo"
container_ds="jdbc/mvdemo"
number_of_mappers="7" />
In the preceding example:
•
The name attribute specifies the map visualizer data source name, which is required
for map requests.
•
The value for the container_ds attribute must match the JNDI Name that you
specified on the Data Source Properties page of the Creating New JDBC Data
Source wizard.
•
The number_of_mappers attribute specifies the maximum number of supported
concurrent map requests that can target this data source.
For more information about these attributes, see Defining Permanent Map Data
Sources.
1.6.2 Creating a Map Visualizer Data Source Using the Oracle RAC
Service Name
As an alternative to creating a JDBC container data source for use with the
container_ds attribute in the map visualizer configuration file (as explained in Creating
a Container Oracle RAC Data Source for the Map Visualizer Server), you can create a
map visualizer data source directly in the map visualizer configuration file by specifying
the connection parameters to the Oracle RAC data service. (This type of connection
works only with Oracle Database Release 11.2 and later.) For example:
<map_data_source name="mvdemo"
jdbc_host="rac.mycompany.com"
jdbc_sid="//srv.mycompany.com"
jdbc_port="1521"
jdbc_user="mvdemo"
jdbc_password="!mypassword"
jdbc_mode="thin"
number_of_mappers="8"
allow_jdbc_theme_based_foi="true"
editable="false"
/>
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In the preceding example:
•
The jdbc_host attribute must be the Oracle RAC SCAN IP address or host name.
•
The jdbc_sid attribute (note the leading // characters in jdbc_sid="//
srv.mycompany.com") specifies the Oracle RAC database service name, not the SID
value.
For more information about the attributes in this example, see Defining Permanent
Map Data Sources.
1.6.3 Restarting the Map Visualizer
After performing the instructions in Creating a Container Oracle RAC Data Source for
the Map Visualizer Server or Creating a Map Visualizer Data Source Using the Oracle
RAC Service Name, you must restart the map visualizer to have the newly created
data source take effect.
After you have restarted the map visualizer, whenever you request a map from the
data source, the map visualizer obtains the necessary database connections (from the
container if you chose the option in Creating a Container Oracle RAC Data Source for
the Map Visualizer Server, or directly from the connection parameters if you chose the
option in Creating a Map Visualizer Data Source Using the Oracle RAC Service
Name).
1.7 High Availability and the Map Visualizer (WebLogic
Server Only)
Users can benefit from the high availability features of Oracle WebLogic Server.
Note:
This section is intended for advanced users who want to take full advantage of
high availability features with the map visualizer. You must have a strong
understanding of high availability features, which are described in Oracle
Fusion Middleware High Availability Guide.
•
Deploying the Map Visualizer on a Middle-Tier Cluster
1.7.1 Deploying the Map Visualizer on a Middle-Tier Cluster
The map visualizer can be deployed to a WebLogic Server cluster. You must take
care, however, about how the generated image files on each host are named and
referenced through URLs by client applications.
Consider the following sample scenario. When a map request is sent to the front web
server, it reaches the map visualizer server running on host A. map visualizer on host
A then sends back the URL for the generated map image, and the client then sends a
second request to fetch the actual image. This second request might be received by
WebLogic Server running on host B, which has no such image (or which will send
back an incorrect image with the same name).
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There is no single best solution for this problem in all environments. One option is to
have the hosts share common networked storage, so that the map images are
deposited in the same virtual (networked) file system by different map visualizer
servers running on different hosts. You must configure the map file storage information
(see Specifying Map File Storage and Life Cycle Information) for each map visualizer
instance so that the images are deposited in different subdirectories or so that they
have different file prefixes. Otherwise, the image files generated by the multiple map
visualizer servers might overwrite each other on the disk. By properly configuring the
map file storage information, you ensure that each URL sent back to the client
uniquely identifies the correct map on the network drive.
If you cannot use networked drives, consider using a load balancer. You may first
need to configure the map file storage information for each map visualizer instance (as
explained in the preceding paragraph), so that each map visualizer instance names its
generated images using an appropriate scheme to ensure uniqueness. You can then
specify rules in the load balancer to have it redirect image requests to a certain host if
the URL matches a certain pattern, such as containing a specified map image file
prefix.
1.8 Secure Map Rendering
You can implement secure map rendering based on a web user's identity.
Users with different roles or permissions will see different feature sets when viewing
the same theme. The basic idea is that the map visualizer will always invoke a
specified PL/SQL package to set the web user's identity in the database whenever
accessing the database for any themes. This user information can be used by the
database to enforce data access control.
Note:
In this section, the terms user and authenticated user refer to the application
or web user that logs into Oracle Fusion Middleware or Oracle Single Sign-On
(SSO). It is not the same as the database user. that the map visualizer itself
will connect directly to a database schema that stores all the geospatial data.
The map visualizer will connect directly to a database schema that stores all the
geospatial data. To enforce access control for the map visualizer on the data in this
schema, you must perform the following steps:
1.
Create a PL/SQL package in the database schema. The package must have at
least two named procedures: set_user(username) and clear_user().
2.
Create views, set access rights on database objects, and perform other tasks,
based on the user identity stored in the PL/SQL package (which is set by the map
visualizer through the set_user procedure for each database session).
3.
Create a map visualizer data source to the schema, providing the name of the
PL/SQL package as part of the data source definition. This is considered a
secured data source.
4.
Create map visualizer themes that are based on the views created in step 2.
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5.
Establish web authentication for users accessing your map visualizer application
page or pages, so that when a map request reaches the map visualizer servlet,
the web session object should contain an authenticated user's identity.
6.
Issue map and FOI (feature of interest) requests that view the themes defined in
step 4, either directly or through the use of base maps and Oracle Maps.
The map visualizer will automatically pass the user identity to the database using
the PL/SQL package before it executes any query for these themes. Only those
rows that are visible to the identified user will be returned from the database and
rendered by the map visualizer.
How Secure Map Rendering Works explains how secure map rendering works and
provides implementation details and examples. Authenticating Users: Options and
Demo describes some options for authenticating users and refers to a supplied demo.
•
How Secure Map Rendering Works
•
Getting the User Name from a Cookie
•
Authenticating Users: Options and Demo
1.8.1 How Secure Map Rendering Works
The map visualizer, as a Java EE application, can obtain the identity of a web user
that has been authenticated to Oracle Fusion Middleware or Oracle Single Sign-On
(SSO). This user information can then be preserved and propagated to the database,
where secure access to map layers and tables can be set up based on the user
identity. For example, a database administrator (DBA) can create a view of a base
table that selects only those spatial features visible to a specific user.
To pass the web user identity from Oracle Fusion Middleware or Oracle Single SignOn (SSO) to the database, use a secure PL/SQL package that sets the user identity in
the database. This PL/SQL package is created by a DBA or application developer and
installed in the data source schema. Such a package can have any number of
procedures and functions, but it must contain at least the following two procedures:
•
set_user(username)
•
clear_user()
Whenever a theme is requested from a secured data source, The map visualizer
invokes the set_user procedure in the associated PL/SQL package before it executes
any data query for the theme, and it invokes the clear_user procedure when the
querying process is complete for the theme.
After you have installed the PL/SQL package, you can pass the name of this package
to the map visualizer as part of the definition of a data source by using the
plsql_package attribute, as shown in Example 1-5.
When you specify a PL/SQL package name in a data source definition, the map
visualizer flags the data source as a secure data source, and it automatically invokes
the package's set_user and clear_user procedures whenever performing any theme
queries on the data source.
Example 1-3
PL/SQL Package for Secure Map Rendering
Example 1-3 shows a PL/SQL package that you can use for secure map rendering.
You can create this package in the example MVDEMO schema.
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In Example 1-3, set_user and clear_user are two required methods, and get_user is a
convenience function that can be used in creating views or for other data access
control purposes
After you create the package (which essentially contains the user identity for the
current database session), you can set up an elaborate virtual private database that
uses this user information (see Oracle Database Security Guide for information about
using Oracle Virtual Private Database, or VPD). For simplicity, however, this section
does not discuss VPD creation, but shows that you can create views that use this user
information to enforce data access control.
For example, in the example MVDEMO schema you can add a column named
ACCOUNT_MGR to the existing CUSTOMERS table, and assign an account manager
to each customer stored in this table. You can then create a view that returns only
customer rows for a specific account manager, as shown in Example 1-4.
CREATE OR REPLACE PACKAGE web_user_info
AS
PROCEDURE set_user (p_name IN VARCHAR2);
PROCEDURE clear_user;
FUNCTION get_user
RETURN VARCHAR2;
END;
CREATE OR REPLACE PACKAGE BODY web_user_info
AS
w_name VARCHAR2 (32767);
PROCEDURE set_user (p_name IN VARCHAR2)
AS
BEGIN
w_name := LOWER (p_name);
END;
PROCEDURE clear_user
AS
BEGIN
w_name := null;
END;
FUNCTION get_user
RETURN VARCHAR2
AS
BEGIN
RETURN w_name;
END;
END;
/
Example 1-4
View for Secure Map Rendering
CREATE OR REPLACE VIEW customers_view
AS
SELECT * FROM customers
WHERE account_mgr = web_user_info.get_user;
You can now define a map visualizer theme based on this view, so that whenever
account managers log in and want to view customer data on a map, each will only see
his or her own customers.
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Example 1-5
Data Source Definition for Secure Map Rendering
<map_data_source name="mvdemo"
jdbc_host="system32.example.com"
jdbc_sid="mv"
jdbc_port="15214"
jdbc_user="mvdemo"
jdbc_password="password"
jdbc_mode="thin"
number_of_mappers="3"
allow_jdbc_theme_based_foi="true"
plsql_package="web_user_info"
/>
1.8.2 Getting the User Name from a Cookie
Sometimes the authenticated user's name is not passed to the map visualizer through
a Java EE or OSSO session. such as when you integrate the map visualizer within
Application Express (APEX), where authentication is carried out by APEX and the user
name is not available through a Java EE or OSSO session. To enable you to work
around this issue, The map visualizer also supports getting the user name from a
cookie. It is your responsibility to set up the cookie within APEX to hold the
authenticated user name.
To ensure that the map visualizer picks up the user name from a named cookie, you
must specify the web_user_type attribute in the data source definition (in addition to the
mandatory plsql_package attribute). For example, if you want the map visualizer to pick
up the user name from a cookie named MON_USER, your secure data source
definition should look like Example 1-6.
Example 1-6
Data Source Definition Specifying Cookie Name
<map_data_source name="mvdemo"
jdbc_host="system32.example.com"
jdbc_sid="mv"
jdbc_port="25650"
jdbc_user="mvdemo"
jdbc_password="LfCDQ6NH59nuV7zbeY5QY06sqN7XhiUQ"
jdbc_mode="thin"
number_of_mappers="3"
allow_jdbc_theme_based_foi="true"
plsql_package="web_user_info"
web_user_type="MON_USER"
/>
The possible values for the web_user_type attribute are:
•
J2EE_USER: tells the map visualizer to get the authenticated user name from a Java
EE session
•
OSSO_USER: tells the map visualizer to get the authenticated user from an OSSO
session.
•
<cookie-name>: tells the map visualizer to get the authenticated user from a cookie
with the specified name. The cookie name is not case sensitive.
If web_user_type is not specified, the map visualizer first looks for the user name in the
Java EE session; and if none is found, it looks for the user name in the OSSO session
(if present).
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1.8.3 Authenticating Users: Options and Demo
How, when, and where users are authenticated depend on the requirements of your
application and the setup of your installation. For example, your options include the
following:
•
Deploy the map visualizer as part of an enterprise portal site, so that end users
always first log onto the portal before performing any mapping functions through
the map visualizer.
•
Deploy the map visualizer on a separate system, and have users authenticate to a
central Oracle SSO server.
As long as the HTTP requests reaching the map visualizer contain the authenticated
user information, the map visualizer will be able to pass the requests on to the
database, and the secure data access approach will work as expected.
1.9 Map Visualizer Demos and Tutorials
Several map visualizer demos and tutorials are included in a separate application
archive named mvdemo.ear, and deployed to the same Java EE container where
mapviewer.ear is deployed.
Once deployed, the demos and tutorials will be accessible from a URL in this format:
http://host:port/mvdemo/
See also the resources available at:
http://www.oracle.com/technetwork/middleware/mapviewer/downloads/
1-38
2
Map Visualization Concepts
This chapter explains concepts that you should be familiar with before using the map
visualizer.
Some fundamental concepts include style, theme, base map, mapping metadata, and
map.
•
Styles define rendering properties for features that are associated with styles. For
example, a text style determines how such a feature is labeled on a map, while a
line style determines the rendition of a linear feature such as a road.
•
A theme is a collection of features (entities with spatial and nonspatial attributes)
that are associated with styles through the use of styling rules.
•
A base map consists of one or more themes. (A base map should not have the
same name as any theme.)
•
Mapping metadata consists of a repository of styles, themes, and base maps
stored in a database.
•
A map is one of the components that the map visualizer creates in response to a
map request. The map can be an image file, the object representation of an image
file, or a URL referring to an image file.
Topics:
•
Overview of the Map Visualizer
When an application uses the map visualizer, it applies specific styles (such as
colors and patterns) to specific themes (that is, collections of spatial features, such
as cities, rivers, and highways) to render a map (such as a GIF image for display
on a web page).
•
Styles
A style is a visual attribute that can be used to represent a spatial feature.
•
Themes
Theme is perhaps the most important concept in the map visualizer. A theme is a
visual representation of a particular data layer.
•
Maps
A map can consist of a combination of elements and attributes.
•
Data Sources
A data source corresponds to a database schema or user.
•
How a Map Is Generated
When a map request arrives at the map visualizer server, the server picks a free
renderer associated with the master data source in the request.
•
Cross-Schema Map Requests
A database user can issue a map request specifying a theme that uses data
associated with another database user, to select data from tables that the other
data source user is authorized to access.
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Overview of the Map Visualizer
•
Workspace Manager Support in the Map Visualizer
Workspace Manager is an Oracle Database feature that lets you version-enable
one or more tables in the database.
•
Map Visualizer Metadata Views
The mapping metadata describing base maps, themes, and styles is stored in the
global tables SDO_MAPS_TABLE, SDO_THEMES_TABLE, and
SDO_STYLES_TABLE, which are owned by MDSYS.
•
Oracle Maps
Oracle Maps is the name for a suite of technologies for developing highperformance interactive web-based mapping applications. It consists of
components from both the server side and the client side.
2.1 Overview of the Map Visualizer
When an application uses the map visualizer, it applies specific styles (such as colors
and patterns) to specific themes (that is, collections of spatial features, such as cities,
rivers, and highways) to render a map (such as a GIF image for display on a web
page).
For example, the application might display a map in which state parks appear in green
and restaurants are marked by red stars. A map typically has several themes
representing political or physical entities, or both. For example, a map might show
national and state boundaries, cities, mountain ranges, rivers, and historic sites. When
the map is rendered, each theme represents a layer in the complete image.
The map visualizer lets you define styles, themes, and base maps, including the rules
for applying one or more styles to each theme. These styles, themes, base maps, and
associated rules are stored in the database in map definition tables under the MDSYS
schema, and they are visible to you through metadata views. All styles in a database
instance are shared by all users. The mapping metadata (the set of styles, themes,
and base maps) that you can access is determined by the map visualizer metadata
views described in Map Visualizer Metadata Views (for example,
USER_SDO_STYLES, USER_SDO_THEMES, and USER_SDO_MAPS). The set of
map definition objects that a given user can access is sometimes called that user's
mapping profile. You can manage styles, themes, and base maps with the standalone
Map Builder tool, described in Oracle Map Builder Tool.
2.2 Styles
A style is a visual attribute that can be used to represent a spatial feature.
The basic map symbols and labels for representing point, line, and area features are
defined and stored as individual styles. Each style has a unique name and defines one
or more graphical elements in an XML syntax.
Each style is of one of the following types:
•
Color: a color for the fill or the stroke (border), or both.
•
Marker: a shape with a specified fill and stroke color, or an image. Markers are
often icons for representing point features, such as airports, ski resorts, and
historical attractions.
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When a marker style is specified for a line feature, the rendering engine selects a
suitable point on the line and applies the marker style (for example, a shield
marker for a U.S. interstate highway) to that point.
•
Line: a line style (width, color, end style, join style) and optionally a center line,
edges, and hash mark. Lines are often used for linear features such as highways,
rivers, pipelines, and electrical transmission lines. You can also use cased line
styles, which are useful for drawing streets and highways.
•
Area: a color or texture, and optionally a stroke color. Areas are often used for
polygonal features such as counties and census tracts.
•
Text: a font specification (size and family) and optionally highlighting (bold, italic)
and a foreground color. Text is often used for annotation and labeling (such as
names of cities and rivers).
•
Advanced: a composite used primarily for thematic mapping, which is described
in Thematic Mapping. The key advanced style is BucketStyle, which defines the
relationship between a set of simple rendering (and optionally labeling) styles and
a set of buckets. For each feature to be plotted, a designated value or set of
values from that feature is used to determine which bucket the feature falls into,
and then the style associated with that bucket is used to plot the feature. Bucket
styles are described in Bucket Styles.
Two special types of bucket styles are also provided: color scheme (described in
Color Scheme Styles) and variable (graduated) marker (described in Variable
Marker Styles). Other advanced styles are dot density (described in Dot Density
Marker Styles), bar chart (described in Bar Chart Marker Styles), collection
(described in Collection Styles), variable pie chart (described in Variable Pie Chart
Styles), and heat map (described in Heat Map Styles).
Table 2-1 lists the applicable geometry types for each type of style.
Table 2-1
Style Types and Applicable Geometry Types
Style Type
Applicable Geometry Types
Color
(any type)
Marker
point, line
Line
line
Area
polygon
Text
(any type)
Advanced
(any type)
All styles for a database user are stored in that user's USER_SDO_STYLES view,
which is described in Map Visualizer Metadata Views and xxx_SDO_STYLES Views.
You can also create dynamically defined styles (that is, temporary styles) of any
style type as part of a map request. To create them, use the Oracle Maps JavaScript
API, using classes and methods to create all types of styles dynamically.
What you are actually creating is the XML definition of the styles; it is the map
visualizer server that actually creates such dynamically defined styles from the
definitions when it processes the map request, and it discards the dynamically created
styles when the request is completed.
•
Scaling the Size of a Style (Scalable Styles)
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Styles
•
Specifying a Label Style for a Bucket
•
Orienting Text Labels and Markers
•
Making a Text Style Sticky
•
Getting a Sample Image of Any Style
•
Allowing a Text Style to Overlap or Be Overlapped
2.2.1 Scaling the Size of a Style (Scalable Styles)
If you specify a unit other than the default of pixels (px) in a style definition, the style
becomes scalable: that is, the size of features associated with the style is scaled as
users zoom in or out on a map. For example, if you specify a marker style's width and
height as 100m, the marker is displayed as a square 100 meters on each side according
to the map scale at the current zoom level.
The following are style types and the attributes that can have an associated size unit:
•
Marker styles: marker size (height and width) and text attributes (font size, label
offsets)
•
Line styles: overall line width, center line width and dash pattern, wing line width
and dash pattern, hash mark, and marker pattern (size, offset, interval)
•
Text styles: font size, halo width
•
Bar chart styles: bar width and height
•
Dot density styles: dot width and height
•
Pie chart styles: pit radius
Example 2-1
Scalable Marker Style
Example 2-1 defines a star-shaped marker within a bounding box 15 kilometers
(15.0km) on each size. This definition might be useful for identifying capital cities of
states on a map showing all or a large part of a country; however, it would not be
useful for a display zoomed in on a specific city and its local surrounding area.
<style name="M.STAR_CAPITAL_CITY">
<svg width="1in" height="1in">
<desc/>
<g class="marker" style="stroke:#000000;fill:#FF0000;fill-opacity:0;width:
15.0km;height:15.0km;font-family:Dialog;font-size:12;font-fill:#FF0000">
<polyline
points="138.0,123.0,161.0,198.0,100.0,152.0,38.0,198.0,61.0,123.0,0.0,76.0,76.0,76.0,
100.0,0.0,123.0,76.0,199.0,76.0"/>
</g>
</svg>
</style>
Example 2-2
Scalable Line Style
Example 2-2 defines a line style with an overall line width of 10 meters (10.0m) and a
border line width of 1 meter (1.0m). This definition might be useful for identifying capital
cities of primary highways.
<style name="L.PRIMARY_HIGHWAY">
<svg width="1in" height="1in">
<desc></desc>
<g class="line" cased="true" style="fill:#33a9ff;stroke-width:10.0m">
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<line class="parallel" style="fill:#aa55cc;stroke-width:1.0m"/>
</g>
</svg>
</style>
When the map visualizer renders or labels styles that have size units other than pixel,
it first transforms the size units into screen pixels based on the current map area and
display area, and it then renders the or labels the style. The size of a scalable style
changes as users zoom in or out on a map. If zooming out results in an overall style
size less than or equal to zero, the style is not rendered or labeled.
Size units can be used only with data associated with a known spatial reference
system (SRS). If the data has no SRS or an unknown SRS, pixels are used for all size
values. Note also that pixel values are used instead of any specified size unit in
legends and in previews rendered by the Map Builder utility. (Legends are explained in
Map Legend.)
2.2.2 Specifying a Label Style for a Bucket
For collection-based bucket styles and individual range-based bucket styles (described
in Bucket Styles and Color Scheme Styles, respectively), you can specify a labeling
style by using the label_style attribute in each bucket element. Example 2-3 creates
an advanced style named V.COUNTY_POP_DENSITY in which each bucket is assigned a
text label style (using the label_style attribute), with some styles being used for
several buckets.
Example 2-3
Advanced Style with Text Label Style for Each Bucket
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets>
<RangedBucket seq="0" label="&lt;150k"
low="-Infinity" high="150000"
style="C.CB_QUAL_8_CLASS_DARK2_1"
label_style="T.BLUE_SERIF_12"/>
<RangedBucket seq="1" label="150k - 350k"
low="150000" high="350000"
style="C.CB_QUAL_8_CLASS_DARK2_2"
label_style="T.BLUE_SERIF_12"/>
<RangedBucket seq="2" label="350k - 600k"
low="350000" high="600000"
style="C.CB_QUAL_8_CLASS_DARK2_3"
label_style="T.BROWN_SERIF_12"/>
<RangedBucket seq="3" label="600k - 1000k"
low="600000" high="1000000"
style="C.CB_QUAL_8_CLASS_DARK2_4"
label_style="T.BROWN_SERIF_12"/>
<RangedBucket seq="4" label="1000k - 1500k"
low="1000000" high="1500000"
style="C.CB_QUAL_8_CLASS_DARK2_5"
label_style="T.GREY_SERIF_12"/>
<RangedBucket seq="5" label="1500k - 2500k"
low="1500000" high="2500000"
style="C.CB_QUAL_8_CLASS_DARK2_6"
label_style="T.GREY_SERIF_12"/>
<RangedBucket seq="6" label="2500k - 5000k"
low="2500000" high="5000000"
style="C.CB_QUAL_8_CLASS_DARK2_7"
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label_style="T.GREEN_SERIF_12"/>
<RangedBucket seq="7" label="&gt;=5000k"
low="5000000" high="Infinity"
style="C.CB_QUAL_8_CLASS_DARK2_8"
label_style="T.GREEN_SERIF_12"/>
</Buckets>
</BucketStyle>
</AdvancedStyle>
For individual range-based buckets, the lower-bound value is inclusive, while the
upper-bound value is exclusive (except for the range that has values greater than any
value in the other ranges; its upper-bound value is inclusive). No range is allowed to
have a range of values that overlaps values in other ranges.
If the V.COUNTY_POP_DENSITY style in Example 2-3 is used in a map request, it displays a
map that might look like the display in Figure 2-1, where the county names are shown
with labels that reflect various text styles (in this case depending on the county's total
population).
Figure 2-1
Varying Label Styles for Different Buckets
In Example 2-3, all buckets except the last one specify a label style. For any features
that fall into a bucket that has no specified label style, the label style (if any) applied to
the feature depends on the following:
•
If the <label> element of the theme's styling rules specifies a label style other than
the advanced style itself, the specified label style is used to label the feature. In
the following example, because the <label> element's style specification
(T.STATE_NAME) is different from the <features> element's style specification
(V.COUNTY_POP_DENSITY), features that fall into a bucket with no specified label style
are labeled using the T.STATE_NAME style:
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule column="TOTPOP">
<features style="V.COUNTY_POP_DENSITY">
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</features>
<label column="county" style="T.STATE NAME">
1
</label>
</rule>
</styling_rules>
•
If the <label> element of the theme's styling rules specifies the advanced style as
its label style, the feature is not labeled. (This is why some counties in Figure 2-1
are not labeled.) In the following example, because the <features> and <label>
elements both specify the advanced style V.COUNTY_POP_DENSITY, features that fall
into a bucket with no specified label style are not labeled:
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule column="TOTPOP">
<features style="V.COUNTY_POP_DENSITY">
</features>
<label column="county" style="V.COUNTY_POP_DENSITY">
1
</label>
</rule>
</styling_rules>
2.2.3 Orienting Text Labels and Markers
You can control the orientation of text labels and markers on a map by using oriented
points. The oriented point is a special type of point geometry in Oracle Spatial and
Graph. In an oriented point, the coordinates represent both the location of the point
and a virtual end point, to indicate an orientation vector. The text is aligned or the
marker symbol is rotated according to the orientation vector, which is explained and
illustrated in Controlling Marker Orientation. For more information about oriented
points, see Oracle Spatial and Graph Developer's Guide.
•
Controlling Text Style Orientation
•
Controlling Marker Orientation
2.2.3.1 Controlling Text Style Orientation
To orient the text label of a point in the direction of an orientation vector, you can
specify the point as an Oracle Spatial and Graph oriented point in the map request.
When the map visualizer labels an oriented point, it automatically centers the text label
on the point position, and aligns the label so that it points in the direction of the
orientation vector.
For each feature to be so labeled, you must specify its location as an oriented point.
You can group these oriented points in a single table and create a spatial index on the
column containing the point geometries. You can then create a theme based on the
table, specifying a desired text style as the labeling, and specifying transparent color
style as the rendering style so that the points themselves are not displayed on the
map.
Example 2-4 is a map request that labels a single oriented point with coordinates
(12,14, 0.3,0.2), where (12,14) represents the X and Y coordinates of the point and
(0.3,0.2) represents the orientation vector. It renders the point using a dynamically
defined transparent color style (named transparent_color) to ensure that the text is
displayed but the underlying point is not displayed.
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Example 2-4
Labeling an Oriented Point
<map_request
title="Labeling Oriented Points"
datasource="my_datasource" width="400" height="300"
antialiase="true"
format="PNG_STREAM">
<themes>
<theme name="theme1">
<jdbc_query
spatial_column="geom" jdbc_srid="8265"
render_style="transparent_color"
label_column="label" label_style="t.street name"
datasource="tilsmenv">
SELECT SDO_GEOMETRY(2001, 8265, NULL,
SDO_ELEM_INFO_ARRAY(1, 1, 1, 3, 1, 0),
SDO_ORDINATE_ARRAY(12, 14, .3, .2))
geom, 'Oriented Point' label FROM dual
</jdbc_query>
</theme>
</themes>
<styles>
<style name="transparent_color">
<svg width="1in" height="1in">
<g class="color" style="stroke:#ff0000;stroke-opacity:0">
<rect width="50" height="50"/>
</g>
</svg>
</style>
</styles>
</map_request>
Figure 2-2 shows part of the map generated by the request in Example 2-4. (The label
is the phrase Oriented Point.)
Figure 2-2
Map Display of the Label for an Oriented Point
2.2.3.2 Controlling Marker Orientation
When a marker style is applied to an oriented point, the map visualizer automatically
rotates the marker style so that it points to the orientation vector. Any necessary
rotation of the marker style is around the center of the marker.
Figure 2-3 shows how you can use an oriented point to control the orientation of
marker styles. In this figure, the original marker style is first shown without any
rotation. However, when the marker is applied to the same oriented point shown in
Example 2-4 in Controlling Text Style Orientation, the marker style is rotated
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accordingly (in this case about 34 degrees counterclockwise) to reflect the orientation
vector.
Figure 2-3
Oriented Marker
2.2.4 Making a Text Style Sticky
You can specify that a text style is "sticky," which means that any feature that uses it
as a label style will always have its text label drawn on a map. Example 2-5 shows an
XML definition of a style with the sticky attribute set to true.
Example 2-5
Text Style with Sticky Attribute
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<desc></desc>
<g class="text" sticky="true" style = "font-style:plain;font-family:Serif;font-size:
11pt;font-weight:bold;fill:#000000">
Hello World!
</g>
</svg>
2.2.5 Getting a Sample Image of Any Style
To get a sample image for any pre-defined style stored in a database, you can issue a
simple HTTP request to the map visualizer server. This request can specify the size of
the sample image, the background color, and the format of the returned image. Such
requests are useful if you want to display a visual list of styles on a web page, to build
a custom map legend, or just to see how various styles will appear.
The HTTP request has the following parameters, all of which are optional except for
sty:
•
sty (required) specifies the name of the style.
•
ds specifies the data source where the style can be accessed. By default, the
default map visualizer data source is used.
•
w specifies the width of the sample image in pixels. The default value is 20.
•
h specifies the height of the sample image in pixels. The default value is 20.
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•
f specifies the format of the sample image. Possible values are png for direct PNG
image stream, png_url for the URL of a PNG image, gif for direct GIF image
stream, or gif_url for the URL of a GIF image. The default value is png, which
means the map visualizer server will directly stream the generated PNG image
data back to the client without first saving it to the server disk.
•
bg specifies the background color of the sample image. The format must be a
hexadecimal string in the form of 0xrrggbb, such as 0x808080 for a gray color. The
default value is 0xffffff (white).
For a transparent background, specify bg as an extended hexadecimal string to
include the alpha values, in the format of 0xaarrggbb. For example, 0x00ffffff will
make the style image's background completely transparent, while 0x55ffffff is a
white background with a transparency value of 0x55 (decimal value 80). The alpha
value can range from 0x00 (completely transparent) to 0xff (completely opaque).
•
aa specifies whether the sample image should be rendered in antialiasing mode.
The default value is the string true. Specify the string false if you do not want to
use antialiasing.
The following example generates an antialiased PNG image with a gray background
with the default size of 20x20 pixels, displaying the marker style named M.STAR from
the map visualizer default data source:
http://www.mycorp.com/mapviewer/omserver?sty=m.star&bg=808080
The preceding request generates a display similar to that in Figure 2-4.
Figure 2-4
Sample Image of a Specified Marker Style
The following example generates an antialiased GIF image with the default white
background, a width of 60 pixels, and a height of 25 pixels, displaying the line style
named L.PH from the map visualizer data source named mvdemo:
http://www.mycorp.com/mapviewer/omserver?sty=l.ph&ds=mvdemo&f=gif&w=60&h=25&aa=true
The preceding request generates a display similar to that in Figure 2-5.
Figure 2-5
Sample Image of a Specified Line Style
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2.2.6 Allowing a Text Style to Overlap or Be Overlapped
You can specify that a text style allow-overlap, which means that any area feature,
such as a polygon that uses it as a label style, will allow its text label be overlapped on
a map. The following example shows an XML definition of a style with the allowoverlap attribute set to true.
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<desc></desc>
<g class="text" allow-overlap="true" style = "font-style:plain;fontfamily:Serif;font-size:11pt;font-weight:bold;fill:#000000">
Hello World!
</g>
</svg>
For example, if a country's name is used as a label text, and if its style has the
attribute value allow-overlap="true", then other features' labels (such as state names)
are allowed to overlap with it. The following figure shows part of a rendered map in
which the country label "United States" overlaps slightly with the state labels
"Colorado" and "Kansas".
Figure 2-6
Text Style with allow-overlap="true"
2.3 Themes
Theme is perhaps the most important concept in the map visualizer. A theme is a
visual representation of a particular data layer.
Conceptually, a theme is a collection of geographic features that share similar
attributes, plus the rendering and labeling rules that tell the map visualizer what styles
to use to render and label the features. To be more exact, when you define a theme,
you are actually providing the map visualizer with the following information: where and
how to get the data, and how to render and label the data.
Depending on how a theme is created, it can also be categorized as either a
predefined theme or a dynamic (JDBC) theme. For a predefined theme, the theme's
definition is created in the standalone Map Builder tool and stored in the database. For
a dynamic theme, the theme's definition (XML) is created in real time by an
application. Dynamic themes typically employee a custom SQL query constructed by
the application to get its data.
Typically, the data for a theme comes from a spatially enabled table, that is, a
database table or view with a column of type SDO_GEOMETRY. For example, a
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theme named US_STATES might be based on a STATES table that has a column named
GEOMETRY, plus any other nonspatial attribute columns. This type of theme is often
called a geometry theme. Besides geometric data, other types of database-managed
geographic data can be associated with corresponding types of themes; for example:
•
Georeferenced images stored in BLOBs (image themes)
•
Oracle Spatial and Graph GeoRaster data (GeoRaster themes)
•
Oracle Spatial and Graph network data model (network themes)
•
Oracle Spatial and Graph topology data model (topology themes)
•
Cartographic annotation text (annotation themes)
Map visualizer themes can be used to render not only geographic data stored in a
database, but also data originating from other sources, such as web services (WFS,
WMS, and WMTS) or the local file system (through the custom spatial data provider
interface).
Regardless of what type of data is associated with a theme (except for WMS and
WMTS themes, which represent externally rendered map layers), the map visualizer
styling rules still need to be defined for each theme, and the styles referenced by the
styling rules must exist and be stored in the database as part of the mapping
metadata.
•
Predefined Themes
•
JDBC Themes
•
Image Themes
•
GeoRaster Themes
•
Network Themes
•
Topology Themes
•
WFS Themes
•
WMTS Themes
•
Custom Geometry Themes
•
Annotation Text Themes
•
LRS (Linear Referencing System) Themes
•
Thematic Mapping
•
Attributes Affecting Theme Appearance
2.3.1 Predefined Themes
A predefined theme is a theme whose definition is stored in a user's database
schema. All predefined themes for a database user are stored in that user's
USER_SDO_THEMES view (described in Map Visualizer Metadata Views, especially
xxx_SDO_THEMES Views). When you include a predefined theme in a map request,
you need to specify only the theme name. The map visualizer automatically finds the
theme's definition, constructs a query based on it, retrieves the relevant spatial and
attribute data, and renders the data according to the styling rules for the theme.
Each predefined theme must have an associated base table or view. If you base a
theme on a view, you must insert a row in the view owner's
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USER_SDO_GEOM_METADATA view (described in Oracle Spatial and Graph
Developer's Guide) specifying the view and its spatial column. If the view is a join view
(that is, if it is based on multiple tables), you must specify the key_column attribute
(described in Themes: Styling Rules) in the theme's styling rules. The reason for this
requirement is that the map visualizer by default caches geometries for a predefined
theme based on the rowid in the base table; however, for a join view there is no
ROWID pseudocolumn, so you must specify a key column.
For most types of predefined themes (but not WMS themes), you can use the Map
Builder tool to create and preview themes. For information about the Map Builder tool,
see Oracle Map Builder Tool.
•
Styling Rules in Predefined Spatial Geometry Themes
•
How the Map Visualizer Formulates a SQL Query for a Styling Rule
•
Styling Rules with Binding Parameters
•
Applying Multiple Rendering Styles in a Single Styling Rule
•
Using Multiple Rendering Styles with Scale Ranges
•
Caching of Predefined Themes
•
Feature Labels and Internationalization
•
Primary and Secondary Labels for Linear Features
2.3.1.1 Styling Rules in Predefined Spatial Geometry Themes
Each predefined theme is always associated with one or more styling rules,
specifications in XML format that control aspects of how the theme is displayed. This
section describes styling rules for predefined spatial geometry themes, such as the
airport theme shown in Example 2-6. Other types of themes, such as image,
GeoRaster, network, and topology themes, have their own distinct styling rules
requirements, and these are discussed in sections that explain these themes.
However, the styling rules for all types of themes are grouped under the
<styling_rules> element in an XML document, which is stored in the
STYLING_RULES column for each predefined theme in the USER_SDO_THEMES
view. (The <styling_rules> DTD is described in Themes: Styling Rules.)
Note:
The following naming conventions are used for prefixes in style names in the
examples in this chapter: v. indicates variable (advanced style), m. indicates
marker, c. indicates color, l. indicates line, and t. indicates text. (If the style
is not under the current user's schema, you must specify the owner's schema
name followed by a colon. For example: mdsys:c.red.)
In the content (character data) of an XML document, &lt; and &gt; must be
used to represent < and >, respectively. Otherwise, < or >, such as in WHERE
CATEGORY > 'B', will be interpreted by the XML parser as part of an XML tag.
Example 2-6
XML Definition of Styling Rules for an Airport Theme
<?xml version="1.0" standalone="yes"?>
<styling_rules>
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<rule>
<features style="c.black gray">
runway_number &gt; 1
</features>
<label column="name" style="t.airport name">
1
</label>
</rule>
<rule>
<features style="m.airplane">
runway_number = 1
</features>
</rule>
</styling_rules>
Each styling rule has a required <features> element and an optional <label> element.
The <features> element specifies which row or rows (features) in the table or view will
be selected based on the user-defined predicate and on the style to be used for the
selected features. You can specify any valid SQL predicate as the value of this
element. The <label> element specifies whether or not to annotate the selected
features, and if so, which column in the table or view to use for text labels.
In Example 2-6, there are two styling rules associated with the Airport theme:
•
The first rule specifies that only those rows that satisfy the condition runway_number
&gt; 1 (that is, runway number greater than 1) will be selected, and these will be
rendered using the style named c.black gray. If no value is supplied, no WHERE
clause condition is applied. For example, assume that the definition had been the
following (that is, omitting the runway_number &gt; 1 condition):
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule>
<features style="c.black gray"/>
<label column="name" style="t.airport name">
1
</label>
</rule>
</styling_rules>
In this case, all airport features would be selected and would be rendered using
the color style named c.black gray.
The first rule also has a <label> element, which specifies that the NAME column in
the table or view will be used to annotate each airport, using the text style
t.airport name. The value of the <label> element, which can be any SQL
expression that evaluates to a numeric value, is used to determine whether or not
a feature will be annotated. If the numeric value is greater than zero, the feature
will be annotated. In this case, because the value is the constant 1, all features
specified by the <features> element will be annotated, using the values in the
NAME column. If the value is less than or equal to zero for a feature, that feature
will not be annotated.
•
The second rule, which applies to those airports with only one runway, does not
have a <label> element, thus preventing all such airports from being annotated. In
addition, the features that satisfy the second rule will be rendered using a different
style (m.airplane), as specified in its <features> element.
You can think of each styling rule as a filter into the base table or view of the theme,
because it selects only a subset of the rows and applies the rendering and labeling
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styles of that rule. In fact, the map visualizer formulates a complete SQL query for
each styling rule. This query string follows a fixed format, as described in How the Map
Visualizer Formulates a SQL Query for a Styling Rule.
2.3.1.2 How the Map Visualizer Formulates a SQL Query for a Styling Rule
To see how the map visualizer formulates a SQL query for a styling rule, consider the
first styling rule from the airport theme example (Example 2-6 in Styling Rules in
Predefined Spatial Geometry Themes):
<styling_rules>
<rule>
<features style="c.black gray">
runway_number &gt; 1
</features>
<label column="name" style="t.airport name">
1
</label>
</rule>
. . .
</styling_rules>
When the map visualizer processes this theme, it formulates a query string for this
styling rule that looks like this:
SELECT ROWID, GEOMETRY, 'C.BLACK GRAY', NAME, 'T.AIRPORT NAME', 1, 'rule#0'
FROM AIRPORT_POINT
WHERE MDSYS.SDO_FILTER(GEOMETRY,
MDSYS.SDO_GEOMETRY(2003, 8265, NULL, MDSYS.SDO_ELEM_INFO_ARRAY(1, 1003, 3),
MDSYS.SDO_ORDINATE_ARRAY(:mvqboxxl, :mvqboxyl, :mvqboxxh, :mvqboxyh)),
'querytype=WINDOW') = 'TRUE'
In the preceding query string:
•
The base table name of the theme, AIRPORT_POINT, appears in the FROM clause
•
The SELECT list includes ROWID as the first column. ROWID is the default
key_column attribute of a predefined theme.
•
The next column in the SELECT list is GEOMETRY. This is the geometry column
of this theme.
•
The next column in the SELECT list is the literal string 'C.BLACK GRAY', which is the
rendering style name for this rule.
•
The next column in the SELECT list is the column NAME, which will provide the
label text. It is specified in the <label> element of this styling rule.
•
The next column in the SELECT list is the literal string 'T.AIRPORT NAME', which is
the labeling style name specified in the <label> element.
•
The next column in the SELECT list is the literal value 1, which is the value of the
<label> element itself.
•
The next column in the SELECT list is the literal string 'rule#0'. This is used
internally by the map visualizer only.
•
The large WHERE clause is essentially an Oracle Spatial and Graph filtering
operator, SDO_FILTER. This WHERE clause is automatically added by the map
visualizer (and is not something you need to specify when defining a theme). It
ensures that only those geographic features that are in contact with the current
map viewing window will be fetched from the base table. The four binding
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variables, mvqboxxl, mvqboxyl, mvqboxxh and mvqboxyh, will be automatically filled in
with the coordinates for the current map viewing window.
The map visualizer always uses the preceding format when constructing SQL queries
for the styling rules of a predefined geometry theme's styling rules. It uses different
formats for the queries for other types of themes, such as a topology or GeoRaster
theme. The formats for these other queries are not described here; however, if you are
interested, you can set the logging level of your map visualizer instance to FINEST,
submit a map request containing a particular type of theme, and check the map
visualizer log file to see the exact query that the map visualizer constructs.
Each row (or feature) in the query's result set now contains all the information the map
visualizer needs: the spatial data, the rendering and labeling style names, the label
text, and the labeling conditions. The map visualizer then constructs an in-memory
feature object for each row and sends them to the rendering pipeline to be displayed
on the map.
If two or more styling rules are specified for a theme, a UNION ALL operation is
performed on the SQL queries for the rules (from first to last) to fetch the qualified
features from the table or view.
If an advanced style is specified in a rule, the SELECT list of the query for that rule will
include the additional attribute column or columns that are required by the advanced
style.
2.3.1.3 Styling Rules with Binding Parameters
As explained in How the Map Visualizer Formulates a SQL Query for a Styling Rule,
the <features> element of a styling rule can define a query condition to select features
from the base table or view. This query condition typically contains hard-coded SQL
expressions, such as runway_num > 1 in the airport theme. However, you can instead
include binding variables in the query predicate. Such a theme is often called a
templated theme, because it is essentially defining a template for how to display
certain features, and the exact set of features is determined at runtime by providing a
binding value to the query predicate.
The concept of templated theme allows you to define a single theme and to have the
binding values change between map requests. For example, consider the following
styling rule:
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule>
<features style="C.RED"> (state_abrv=:1) </features>
<label column="STATE" style="T.STATE NAME"> 1 </label>
</rule>
</styling_rules>
The preceding styling rule defines a <features> element with a query condition based
on the value of the state_abrv attribute, which the application must supply. In map
visualizer requests, the binding parameter must be defined on the theme section, and
each binding parameter is defined by a value and by a SQL type. In the following
theme definition on a map request, the state abbreviation value is ME and the variable
SQL type is String. The value ME will be used with the predefined theme styling rule.
<theme name="THEME_US_DYN_STATES" >
<binding_parameters>
<parameter value="ME" type="String"/>
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</binding_parameters>
</theme>
2.3.1.4 Applying Multiple Rendering Styles in a Single Styling Rule
The <feature> element of a styling rule allows you to specify only one rendering style
using the style attribute. If you want to apply multiple rendering styles to a feature
without using multiple themes, you cannot specify multiple styling rules, because each
rule selects a different subset of features. To apply multiple rendering styles to a
feature without using multiple themes, you must use the <rendering> element instead
of the style attribute of the <features> element.
The <rendering> element has the format shown in the following example:
<rendering>
<style name="V.POIVMK" value_columns="FEATURE_CODE">
<substyle name="V.POIVBKT" value_columns="POINT_ID" changes="FILL_COLOR"/>
</style>
</rendering>
In the <rendering> element, the <style> element specifies the name of the style to use
when rendering features, and one or more value columns (comma-delimited) for use
with advanced styles. In the preceding example, the style name is V.POIMVK and the
value column is FEATURE_CODE.
In the <style> element, the <substyle> element enables rendering of a feature using a
combination of two attribute values.,such as defining the feature shape by the <style>
element and the feature color by the <substyle> element. This is useful for rendering
point features once but based on two attribute values. You can specify one or more
value columns (comma-delimited), and the change to be applied (only FILL_COLOR is
currently supported).
You can specify multiple <style> elements with a <rendering> element, to achieve the
following goals:
•
To create an advanced style in which a base advanced style, associated with
some attributes (columns), can have its rendering affected by some other
attributes through the use of a substyle. For example, an advanced style can
display markers of different sized based on one value column, while using a
secondary color style to change the fill color of those markers based on another
value column.
•
To use multiple styles to render a feature (achieving the effect of stacked styles).
Example 2-7 shows a predefined theme styling rule that uses the <rendering> element.
The <features> element is part of the rules and must be define, because it also
specified the query condition, but no style attribute is specified. The <rendering>
element defines how to render the features.
Example 2-7
Styling Rules Using the <rendering> Element
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule>
<features> </features>
<label column="NAME" style="T.STREET2"> 1 </label>
<rendering>
<style name="V.POIVMK" value_columns="FEATURE_CODE">
<substyle name="V.POIVBKT" value_columns="POINT_ID" changes="FILL_COLOR"/>
</style>
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</rendering>
</rule>
</styling_rules>
The <rendering> element can also be used with dynamic themes, geometry themes,
and topology themes.
2.3.1.5 Using Multiple Rendering Styles with Scale Ranges
The <rendering> element (see Applying Multiple Rendering Styles in a Single Styling
Rule) can have multiple <style> elements defined. You can also assign scale ranges
for each <style> element. By using multiple stacked styles with scale ranges, you can
define a single theme with different representations for different scales.
Example 2-8 shows the theme styling rules with stacked styles. Each style has a scale
range defined.
Example 2-8
Theme Styling Rules with Stacked Styles
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule>
<features> </features>
<label column="STATE" style="T.S02_STATE_ABBREVS"> 1 </label>
<rendering>
<style name="C.COUNTIES" max_scale="5.0E7" scale_mode="RATIO"/>
<style name="C.RB13_1" min_scale="5.0E7" max_scale="1.0E7" scale_mode="RATIO"/>
<style name="L.DPH" min_scale="1.0E7" scale_mode="RATIO"/>
</rendering>
</rule>
</styling_rules>
2.3.1.6 Caching of Predefined Themes
By default, the map visualizer automatically caches the spatial data for a predefined
theme when it is fetched from the database for processing by the map visualizer
rendering engine. By contrast, data for dynamic (JDBC) themes is never cached in the
map visualizer. If you do not want any data for a predefined theme to be cached (such
as for a theme whose underlying base table is constantly being updated), you can set
the caching attribute to NONE in the <styling_rules> element for the theme. (The
<styling_rules> element, including the caching attribute, is described in Themes:
Styling Rules.)
For frequently used themes whose base data is static or read-only, specify caching ALL
for the best performance. This causes the map visualizer, when it first accesses the
theme definition, to fetch all the features (including spatial data, attribute data, and
styling information associated with them) and cache them in the map visualizer
memory, creating an in-memory R-tree for the theme's spatial data. All subsequent
requests requiring that theme occur locally instead of going to the database.
If the caching attribute value is NORMAL (the default), each time a map involving that
theme is requested, the map visualizer queries the database to get the spatial data
and any associated attribute data. However, if any of the spatial geometry data, as
referenced by rowid or a user-specified key column, has already been cached, the
unpickling process (the conversion from the raw database geometry format to a Java
geometry object) is skipped. Still, if memory is not an issue and if a frequently used
theme can completely fit in the cache, you should specify caching ALL, to eliminate
virtually all database access for that theme after the initial loading.
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Because the map visualizer spatial data cache is global, all predefined themes that are
accessed by the map visualizer compete for a global fixed-sized memory cache. The
cache resides completely in memory, and you can specify the maximum size of the
cache as explained in Customizing the Spatial Data Cache. When the cache limit is
reached, older cached data is removed from the cache to make room for the most
recently accessed data, except that data for themes specified with caching ALL is not
removed from the cache, and the map visualizer does not requery the database for
these themes.
Caching is currently disabled for predefined annotation and custom geometry themes.
For custom geometry themes, you can implement a caching mechanism in your
provider implementation. However, for each request, a new instance of your provider
is created; and if you implement a local caching mechanism, it will be lost.
2.3.1.7 Feature Labels and Internationalization
The map visualizer includes support for translated theme labels. Typically with a
predefined map visualizer theme, you can specify a label column that will provide all
the text strings for labeling each feature of the theme. These text strings are string
values stored in the database table column, in a specific language (such as English).
However, you can also supply different translations of these stored string values by
using a resource bundle. When such translated text strings are available, you can
instruct the map visualizer to label the features of a theme using a specific language or
locale.
Note:
Only predefined geometry themes support resource bundles at this time.
The steps for supplying translations and instructing the map visualizer to label a theme
using a specific user language are as follows:
1.
Prepare the translations.
A typical map visualizer predefined geometry theme gets all the underlying data
from a table. You can specify one of the (string type) columns as the labeling
column for this theme. This is called the label column. When a label column needs
to be translated into different languages, you extract all the values from the table,
and store them in a properties file, such as StringResources.properties. (Note that
the file name StringResources.properties assumes that the extracted texts are all
in English. If they are not, then the properties file name needs to follow a
convention where the language code, and an optional region or country code, is a
suffix in the file name. For example, StringResources_fr.properties will contain
French translations only, while StringResources_zh_CN.properties is for simplified
Chinese.)
A properties file is a plain text file that follows a very simple format. For example, a
simple StringResources.properties file might contain the following:
# This is the English version of the strings.
California = California
Nevada = Nevada
Montana = Montana
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The first line is a comment, and starts with the # character. Each subsequent line
contains one pair of key (first string) and value (second string). The keys come
directly from the label column, whereas the values are corresponding translations.
Because this particular file contains the default English text strings, the key and
the value (translation) are the same in each case. Note that the keys should
always be in English.
From this default properties file, your translation specialists should create a set of
property files, one file for each translation. Using the preceding simple example,
the translated file for simplified Chinese (StringResources_zh_CN.properties) should
look like the following, in which the value of each key has been replaced by the
Chinese translation of the key, encoded as a Unicode string:
# This is the Chinese version of the strings.
California = \u6CA1\u6709\u8981\u5448\u73B0\u7684\u4E3B\u9898\u3002
Nevada = \u65E0\u6CD5\u52A0\u8F7D\u4E3B\u9898\u3002
Montana = \u65E0\u6CD5\u52A0\u8F7D\u6837\u5F0F\u3002
The default properties file, StringResouces.properties, plus all the language
specific files that share the same file name (except for the language and region
suffixes) collectively form what is called a resource bundle. In this case the
resource bundle is named StringResources. You can name your resource bundles
with any name you like, but different bundles (containing different set of keys)
should always use different base names.
For more information about Java resource bundles and properties files, see the
Java language documentation.
2.
Supply the translated text strings as a Java Resource Bundle, which can be based
on either Java resource classes or plain properties files.
After all the label text strings have been translated, you must place all the files (the
resource bundle) in the map visualizer CLASSPATH so that the map visualizer
can find these files at runtime. Typically, you can use the map visualizer WEB-INF/
classes folder: copy all the files including the base StringResources.properties and
language-specific files (such as StringResources_fr.properties and
StringResources_zh_CN.properties) into this folder.
If you place all the files of a resource bundle into a subfolder under WEB-INF/
classes, then the name of the resource bundle (as known to the map visualizer)
will need to be prefixed with this subfolder name. This is similar to how one places
a Java class in a directory structure that follows the package names. For example,
if you put all the StringResources*.properties files in WEB-INF/classes/i18n/, then
later when you register the resource bundle with the map visualizer, the actual
name of your resource bundle should be i18n.StringResources.
3.
Specify the name of the resource bundle in the theme definition by registering the
resource bundle with the map visualizer.
For the map visualizer to find your translated classes, you must specify the
complete name of your resource bundle in the theme definition. The easiest way to
do this is with the Map Builder utility, specifying the resource bundle name as the
Translation Class in the Advanced Parameters pane of the theme editor.
Figure 2-7 shows StringResources being specified for the Translation Class.
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Figure 2-7
Specifying a Resource Bundle for a Theme
As mentioned in the preceding step, if your resource bundle files are located in a
subfolder of , then the subfolder name must the base name of your resource
bundle, separated by a period, as if the resource bundle files were Java classes in
a package.
4.
Specify a language parameter when requesting a map or theme.
Specify the preferred language for each map request the Oracle Maps JavaScript
API (described in Oracle Maps JavaScript API) or the XML map request API
(described in Map Visualization Servers).
•
In JavaScript code, specify the label language code in the call to the
MVThemeBasedFOI class. The following example causes the FOI theme to
display its labels in simplified Chinese:
themebasedfoi = new
MVThemeBasedFOI('themebasedfoi1','mvdemo.theme_demo_states');
themebasedfoi.setLabelLanguageCode("zh-cn");
themebasedfoi.enableLabels(true);
With the setLabelLanguageCode(lang_code) method, you can specify a language
code so that the map visualizer labels the features using the text strings for the
specified language, which must be a 2 letter language code (such as zh),
followed optionally a hyphen (-) and a 2-letter country code (such as zh-cn).
The language codes are defined by the ISO 639 standards and are listed at
several websites, such as http://www.loc.gov/standards/iso639-2/php/
English_list.php. If no translated text strings for the specified language code
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are found, the English text strings (or whatever the default strings are for the
theme) will be used for labeling.
•
In an XML map request, specify the language in the lang attribute. The
following example causes the labels to be displayed in simplified Chinese:
<map_request title="Oracle LBS MAP"
basemap="demo_map"
datasource = "mvdemo"
width="640" height="480"
lang="zh-CN"
format="PNG_STREAM">
<center size="5.15">
<geoFeature> <geometricProperty typeName="center">
<Point> <coordinates>-122.2615, 37.5266</coordinates>
</Point> </geometricProperty>
</geoFeature>
</center>
</map_request>
Only language codes and country codes specified by the ISO 639 standards
can be used as possible lang values. If an optional country code is used, it
must be connected to the language code by a hyphen (-). Country codes and
language codes are not case sensitive.
If the lang attribute is specified as part of the XML map request, every theme
rendered to the result map it checked to see if it has an associated resource
bundle. If a theme does not have an associated resource bundle, or the
translated text strings for the specified language cannot be found, the default
values (those stored in the table column) are used.
If the lang attribute is not specified as part of the XML map request, the default
text string values (those stored in the table column) are always used,
regardless of which locale in effect for the map visualizer itself (or rather, its
containing JVM).
2.3.1.8 Primary and Secondary Labels for Linear Features
The map visualizer includes support for labeling a linear feature with a primary and a
secondary label. For example, a street name can be labeled with its English name as
the primary label and with its local (native) language as the secondary label (or vice
versa). When labeling a linear feature, the primary and secondary labels are labeled
alternately along the feature when applicable.
When you specify a label column for a map visualizer theme, that column will provide
both the primary and secondary text strings, delimited by "|||" (three vertical lines). For
example, a text string of "Garden St|||Rua Jardim" contains the primary text string of
"Garden St" (English) and secondary text string of "Rua Jardim" (Portuguese). In
practice, that label column may be a concatenation of two existing columns, and
database triggers can be employed to maintain its consistency with its two base
columns.
2.3.2 JDBC Themes
A JDBC theme is a theme that is dynamically defined with a map request. JDBC
themes are not stored permanently in the database, as is done with predefined
themes.
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For a JDBC theme, you must specify a valid SQL query that retrieves all the necessary
spatial data (geometries or other types of data, such as image, GeoRaster, network, or
topology). If attribute data is needed, such as for thematic mapping or spatial data
analysis, the query must also select it. In other words, you must provide a correct and
complete query for a JDBC theme. In addition to the query, you can also specify the
rendering and labeling styles to be used for the theme.
For a JDBC theme based on spatial geometries, the map visualizer processed the
columns specified in the query according to the following rules:
•
The column of type SDO_GEOMETRY is treated as the spatial data column.
•
Any column whose name or alias matches that specified in the JDBC theme's
label_column attribute is treated as the labeling column, whose values are used as
text for labels.
•
Any other columns are treated as attribute data columns, which may or may not be
used by the map visualizer. For example, if the rendering style is an advanced
style, any attribute columns are processed by that style in the order in which they
appear in the SELECT list in the query. Thus, if you are performing thematic
mapping and using an advanced style, you must specify all attribute columns that
are needed for the thematic mapping, in addition to the geometry column and
optional labeling column. (A labeling column can also be an attribute column, in
which case you do not need to specify that column in the SELECT list.)
Example 2-9 is a map request that includes a JDBC theme.
Example 2-9
JDBC Theme in a Map Request
<?xml version="1.0" standalone="yes"?>
<map_request title="My MAP" datasource = "mvdemo">
<themes>
<theme name="jdbc_theme_1">
<jdbc_query
datasource="mvdemo"
jdbc_srid="41052"
spatial_column="geometry"
render_style="C.RED">
SELECT geometry from states where name='MA'
</jdbc_query>
</theme>
</themes>
</map_request>
The full query that the map visualizer executes for the JDBC theme in Example 2-9 is:
SELECT geometry FROM states WHERE name='MA';
For this request, the map visualizer generates a map that contains only the selected
geometry as a result of executing this JDBC theme's query. In a more typical case,
however, the map request will need to use several JDBC themes to plot additional
dynamic data on top of the base map. Furthermore, the map request may have a
query window associated with it; that is, the user may want to see only a portion of the
area included in the whole base map. In this case, the SQL queries in the JDBC
themes will be subjected to a spatial window query, to eliminate any unwanted results.
•
Defining a Point JDBC Theme Based on Two Columns
•
Storing Complex JDBC Themes in the Database
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2.3.2.1 Defining a Point JDBC Theme Based on Two Columns
If a database table uses two columns (such as longitude and latitude) to represent a
point coordinate, you can define a JDBC theme based on the two columns to render
points. The table does not need to have a spatial geometry column, but it can have
one; however, if the theme request defines the point columns and also the geometry
column, the map visualizer will try to render the points using the two columns, not the
geometry column.
Example 2-10 is a JDBC theme that renders points from two columns, named
LONG_LOC and LAT_LOC, of a table named POI. The x_column and y_column
attributes specify the columns containing the point coordinate values. In this example,
the points are rendered using the C.RED style, and the table values from the NAME
column are rendered using the T.POI_NAME style.
Example 2-10
JDBC Theme Based on Columns
<map_request>
. . .
<center>
. . .
</center>
<themes>
<theme name="theme1" >
<jdbc_query
datasource="mvdemo"
jdbc_srid="8265"
x_column="long_loc"
y_column="lat_loc"
render_style="C.RED"
label_column="name"
label_style="T.POI_NAME"
>SELECT long_loc, lat_loc,name FROM poi
</jdbc_query>
</theme>
</themes>
</map_request>
If the request specifies a valid query window (that is, not the full extent), a WHERE
expression based on the size of the request window is automatically added to the
query.
Example 2-11
JDBC Theme Based on Columns, with Query Window
If the table has a geometry column, you can specify SQL code to use the geometry
column as a filter. Example 2-11 is similar to Example 2-10, but it adds the use of the
SDO_FILTER operator to specify a query window based on the geometry in the
column named GEOMETRY. In Example 2-11, the question mark (?) characters
indicate that the lower-left and upper-right coordinates of the query window rectangle
are taken from values supplied at runtime (not shown in this example).
<map_request>
. . .
<center>
. . .
</center>
<themes>
<theme name="theme1" >
<jdbc_query
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datasource="mvdemo"
jdbc_srid="8265"
x_column="long_loc"
y_column="lat_loc"
render_style="C.RED"
label_column="name"
label_style="T.POI_NAME"
>SELECT long_loc, lat_loc FROM poi WHERE
SDO_FILTER(geometry,MDSYS.SDO_GEOMETRY(2003, 8265, NULL,
MDSYS.SDO_ELEM_INFO_ARRAY(1, 1003, 3),
MDSYS.SDO_ORDINATE_ARRAY(?,?,?,?)),
'querytype=WINDOW') = 'TRUE'
</jdbc_query>
</theme>
</themes>
</map_request>
2.3.2.2 Storing Complex JDBC Themes in the Database
Sometimes the SQL query for a JDBC theme is so complex that you may want to save
the query. In such cases, you can define a predefined theme (whose definition is
stored in the database's USER_SDO_THEMES view), and then include the full SQL
query as the content of the <features> element in the styling rules for that theme.
The feature style specified in the <features> element is then used to render the
geometries retrieved using the full query. The base table as defined for such a theme
is ignored because the full SQL query already includes a FROM clause. The geometry
column defined in the USER_SDO_THEMES view is still needed, and it must be the
same as the geometry column selected in the user-supplied SQL query. If you have a
<label> element for a styling rule, the label style specified is used to label the
geometries, as long as the query selects a column that contains label text.
Example 2-12 is a sample <styling_rules> element of a predefined theme with a
complex SQL query.
Example 2-12
Complex Query in a Predefined Theme
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule>
<features style="L.POOR_ROADS" asis="true">
select sdo_lrs.clip_geom_segment(geometry,start_measure,end_measure)
geometry
from (select /*+ no_merge use_hash(a b) */
a.street_id, name, start_measure, end_measure, geometry
from (select /*+ no_merge */ a.street_id, name, geometry
from philly_roads a
where sdo_filter(geometry,sdo_geometry(2002,41124,null,
sdo_elem_info_array(1,2,1),
sdo_ordinate_array(?,?,?,?)),
'querytype=window')='TRUE') a,
philly_road_conditions b
where condition='POOR' and a.street_id = b.street_id)
</features>
</rule>
</styling_rules>
Even though Example 2-12 is defined as a predefined theme, the map visualizer still
treats it as a JDBC theme at runtime when a user requests a map that includes this
theme. As with a normal JDBC theme, the map visualizer by default imposes a window
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filtering process (if a query window was included in the map request) on top of the
SQL query. To override this default behavior and have the supplied query string
executed without any modification, specify asis="true" in the <features> element, as
shown in Example 2-12.
2.3.3 Image Themes
An image theme is a special kind of map visualizer theme useful for visualizing
geographically referenced imagery (raster) data, such as from remote sensing and
aerial photography.
You can define an image theme dynamically or permanently (as a predefined theme)
in the database. You can use image themes with vector (nonimage) themes in a map.
Figure 2-8 shows a map in which an image theme (showing an aerial photograph of
part of the city of Boston) is overlaid with themes showing several kinds of roadways in
the city.
Figure 2-8
Image Theme and Other Themes Showing Boston Roadways
Before you can define an image theme, you must follow these rules in organizing your
image data:
•
Store image data in its original format (such as JPEG) in a BLOB column in a
database table, or as an Oracle Multimedia object (ORDSYS.ORDImage) that
points to the original image file. For information about creating an
ORDSYS.ORDImage object, see Oracle Multimedia User's Guide.
•
Add a geometry (SDO_GEOMETRY) column to the same table, and store the
minimum bounding rectangle (MBR) for each image in that column.
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Each geometry in the MBR column contains the geographic bounds for an image,
not its size in the pixel space. For example, if an orthophoto image is 2000 by
2000 pixels in size, but covers a ground rectangle starting at the corner of
(936000, 248000) and having a width and height of 8000 meters, the MBR for the
geometry column should be populated with (936000, 248000, 944000, 256000).
•
Insert an entry for the geometry column in the USER_SDO_GEOM_METADATA
view.
•
Create a spatial index on the geometry column.
To predefine an image theme, follow the guidelines in Creating Predefined Image
Themes. To define a dynamic image theme in a map request, follow the guidelines for
defining a JDBC theme, as explained in JDBC Themes, but note the following
additional considerations with dynamic image themes:
•
You must provide the original image resolution information when defining an
image theme.
•
The map visualizer by default automatically scales the image data when
generating a map with an image theme, so that it fits the current query window. To
disable this automatic scaling, specify imagescaling="false" in the map request.
For any image theme definition, the map visualizer supports only GIF, JPEG, PNG,
and TIFF image formats.
•
Creating Predefined Image Themes
2.3.3.1 Creating Predefined Image Themes
To create a predefined image theme, you must store the definition of the image theme
in the database by inserting a row into the USER_SDO_THEMES view (described in
xxx_SDO_THEMES Views). Example 2-13 stores the definition of an image theme.
•
theme_type must be image in order for this theme to be recognized as an image
theme.
•
image_column specifies the column in the base table or view that stores the actual
image data.
•
image_format is a string identifying the format of the image data. If you specify GIF
or JPEG, the map visualizer can always render the image data.
•
image_resolution is an optional attribute that identifies the original image resolution
(number of image_unit units for each pixel).
•
image_unit is an optional attribute, except it is required if you specify the
image_resolution attribute. The image_unit attribute specifies the unit of the
resolution, such as M for meter. The value for this attribute must be one of the
values in the SDO_UNIT column of the MDSYS.SDO_DIST_UNITS table. In
Example 2-13, the image resolution is 2 meters per pixel.
The DTD for the <styling_rules> element is presented in Themes: Styling Rules.
Example 2-13
Creating a Predefined Image Theme
INSERT INTO user_sdo_themes VALUES (
'IMAGE_LEVEL_2',
'Orthophotos at pyramid level 2',
'IMAGES',
'IMAGE_MBR',
'<?xml version="1.0" standalone="yes"?>
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<styling_rules theme_type="image" image_column="image"
image_format="JPEG" image_resolution="2"
image_unit="M">
<rule >
<features style="C.RED"> plevel=2 </features>
</rule>
</styling_rules>' );
Example 2-13 creates an image theme named IMAGE_LEVEL_2. The base table (where
all image data and associated MBRs are stored) is named IMAGES, and the minimum
bounding rectangles (MBRs) for the images are stored in the column named
IMAGE_MBR. In the STYLING_RULES column of the USER_SDO_THEMES view, an
XML document with one <styling_rules> element is inserted.
The <styling_rules> element for an image theme has the following attributes:
2.3.4 GeoRaster Themes
A GeoRaster theme is a special kind of map visualizer theme useful for visualizing
GeoRaster objects. GeoRaster is a feature of Oracle Spatial and Graph that lets you
store, index, query, analyze, and deliver raster image and gridded data and its
associated metadata. GeoRaster objects are defined using the SDO_GEORASTER
data type. For detailed information about GeoRaster, see Oracle Spatial and Graph
GeoRaster Developer's Guide.
Before you can use the map visualizer with GeoRaster themes, you must ensure that
the Java Advanced Imaging (JAI) library files (jai_core.jar and jai_codec.jar) are in
the map visualizer library path. You must also perform the following actions with the
GeoRaster data:
1.
Georeference the GeoRaster data to establish the relationship between cell
coordinates of the GeoRaster data and real-world ground coordinates (or some
other local coordinates).
If you are using Oracle Database Release 10.1, you must also set the spatial
resolution values.
2.
Generate or define the spatial extent (footprint) associated with the raster data.
3.
Optionally, generate pyramid levels that represent the raster image or data at
different sizes and degrees of resolution.
4.
Insert a row into the USER_SDO_GEOM_METADATA view that specifies the
name of the GeoRaster table and the SPATIALEXTENT attribute of the GeoRaster
column (that is, the column of type SDO_GEORASTER). The following example
inserts a row for a table named GEOR_TABLE with a GeoRaster column named
GEOR_COLUMN:
INSERT INTO USER_SDO_GEOM_METADATA VALUES
( 'geor_table',
'geor_column.spatialextent',
SDO_DIM_ARRAY(
SDO_DIM_ELEMENT('X', 496602.844, 695562.844, 0.000005),
SDO_DIM_ELEMENT('Y',8788409.499,8973749.499, 0.000005)
),
82279 -- SRID
);
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5.
Create a spatial index on the spatial extent of the GeoRaster table. The following
example creates a spatial index named GEOR_IDX on the spatial extent of the
table named GEOR_TABLE:
CREATE INDEX geor_idx ON geor_table(geor_column.spatialextent)
INDEXTYPE IS MDSYS.SPATIAL_INDEX;
Example 2-17 in Creating Predefined GeoRaster Themes prepares GeoRaster data
for use and stores a GeoRaster theme in the database.
The map visualizer supports two types of map requests with objects from a GeoRaster
table:
•
A request containing a SQL statement to select one or more GeoRaster objects
•
A request specifying a single GeoRaster object by the combination of its raster
data table name and its rasterID attribute value in the SDO_GEORASTER object.
(The rasterID attribute value in the SDO_GEORASTER object is distinct from and
unrelated to any primary key or ID column in the GeoRaster table.)
The following elements and attributes apply to the definition of a GeoRaster theme:
•
<jdbc_georaster_query> element: Specifies that this is a dynamically defined
GeoRaster theme. For a theme that uses a SQL statement to select one or more
GeoRaster objects, this element contains the SQL query statement (without a
terminating semicolon).
•
georaster_table attribute: Specifies the name of the GeoRaster table.
•
georaster_column attribute: Specifies the name of the column of type
SDO_GEORASTER in the GeoRaster table.
•
polygon_mask attribute (optional): Specifies a set of two-dimensional coordinates
representing a polygon, to be used as a mask to make transparent the part of the
GeoRaster image that is outside the polygon mask. The coordinates are defined
as x1,y1,x2,y2, . . . . The mask coordinates must be in the data coordinate space.
•
raster_bands attribute (optional): Specifies the band composition to be assigned to
the red, green, and blue channels. If you specify only one value, the resulting
image uses one band (gray levels for monochromatic images). If you specify two
values, they are used for the red and green channels, and the default blue band
stored in the GeoRaster metadata is used for the blue channel. If you do not
specify this attribute, the map visualizer uses the default values stored in the
GeoRaster metadata.
•
raster_pyramid attribute (optional): Specifies the pyramid level (level of resolution).
If you do not specify this attribute, the map visualizer calculates the best pyramid
level for the current window query and device area.
•
raster_id attribute (only if the definition does not include a SQL statement):
Specifies the rasterID attribute value in the SDO_GEORASTER object definition
of the single GeoRaster object for the map request.
•
raster_table attribute (optional, and only if the definition does not include a SQL
statement): Specifies the raster data table associated with the single GeoRaster
object for the map request.
•
transparent_nodata attribute (optional): Specifies if any GeoRaster NODATA value
is to be rendered as transparent. The default value is "false".
Example 2-14 defines a GeoRaster theme that contains a SQL statement that selects
a single GeoRaster object. The theme assigns band 1 to the red channel, band 2 to
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the green channel, and band 3 to the blue channel. Because the raster_pyramid
attribute is not specified, the map visualizer calculates the best pyramid level by using
the spatial resolution values set during or after the georeferencing process. (In
Example 2-14, georid=1 in the WHERE clause refers to a column named GEORID in
the GeoRaster table named PCI_IMAGE.)
Example 2-15 defines a GeoRaster theme that specifies the single GeoRaster object
whose rasterID attribute value in the SDO_GEORASTER object is 1 (raster_id="1")
and associated with the raster data table named RDT_PCI. The theme specifies 2 as
the pyramid level.
Subtopics:
•
Creating Predefined GeoRaster Themes
•
Using Bitmap Masks with GeoRaster Themes
•
Reprojection of GeoRaster Themes
•
Virtual Mosaic Themes
Example 2-14
GeoRaster Theme Containing a SQL Statement
<theme name="georaster_theme">
<jdbc_georaster_query
georaster_table="pci_image"
georaster_column="georaster"
raster_bands="1,2,3"
jdbc_srid="82301"
datasource="mvdemo"
asis="false"> SELECT georaster FROM pci_image WHERE georid =1
</jdbc_georaster_query>
</theme>
Example 2-15
GeoRaster Theme Specifying a Raster ID and Raster Data Table
<theme name="georaster_theme">
<jdbc_georaster_query
georaster_table="pci_image"
georaster_column="georaster"
raster_id="1"
raster_table="rdt_pci"
raster_pyramid="2"
raster_bands="1,2,3"
jdbc_srid="82301"
datasource="mvdemo"
asis="false">
</jdbc_georaster_query>
</theme>
•
Creating Predefined GeoRaster Themes
•
Using Bitmap Masks with GeoRaster Themes
•
Reprojection of GeoRaster Themes
•
Virtual Mosaic Themes
2.3.4.1 Creating Predefined GeoRaster Themes
To create a predefined GeoRaster theme, you must store the definition of the
GeoRaster theme in the database by inserting a row into the USER_SDO_THEMES
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view (described in xxx_SDO_THEMES Views). Example 2-16 stores the definition of a
GeoRaster theme.
Example 2-16 creates a GeoRaster theme named GEOR_BANDS_012, in which band 0 is
assigned to the red channel, band 1 to the green channel, and band 2 to the blue
channel. The GeoRaster table name (GEOR_TABLE in this example) is inserted in the
BASE_TABLE column of the USER_SDO_THEMES view, the GeoRaster column
name (GEOR_COLUMN in this example) is inserted in the GEOMETRY_COLUMN
column, and an XML document with one <styling_rules> element is inserted in the
STYLING_RULES column.
In the <styling_rules> element for a GeoRaster theme, theme_type must be georaster
in order for this theme to be recognized as a GeoRaster theme.
The <styling_rules> element for a GeoRaster theme can contain the attributes
described in GeoRaster Themes, including raster_bands, raster_pyramid, raster_id,
and raster_table, as shown in Example 2-16. Alternatively, the <styling_rules>
element for a GeoRaster theme can be a rule definition. For example, to create a
GeoRaster theme that selects a GeoRaster object from the GeoRaster table satisfying
the WHERE clause condition georid=1, replace the <styling_rules> element in
Example 2-16 with the following:
<styling_rules theme_type="georaster">
<rule>
<features> georid=1
</features>
</rule>
</styling_rules>
The <styling_rules> element for a GeoRaster theme can also specify one or more
bitmap masks, as explained in Using Bitmap Masks with GeoRaster Themes.
The DTD for the <styling_rules> element is presented in Themes: Styling Rules.
Example 2-17 prepares GeoRaster data for use with a GeoRaster theme that is stored
in the database. Comments in the code example briefly describe the main steps. For
detailed information about requirements and steps for using GeoRaster data, see
Oracle Spatial and Graph GeoRaster Developer's Guide.
Example 2-16
Creating a Predefined GeoRaster Theme
INSERT INTO user_sdo_themes VALUES (
'GEOR_BANDS_012',
'Band 0 for red, 1 for green, 2 for blue',
'GEOR_TABLE',
'GEOR_COLUMN',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="georaster" raster_table="RDT_PCI"
raster_id="1" raster_bands="0,1,2">
</styling_rules>' );
Example 2-17
Preparing GeoRaster Data for Use with a GeoRaster Theme
connect scott
Enter password: password
SET
SET
SET
SET
ECHO ON
FEEDBACK 1
NUMWIDTH 10
LINESIZE 100
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SET PAGESIZE 10000
SET SERVEROUTPUT ON SIZE 5000
SET LONG 20000
SET TIMING ON
call dbms_java.set_output(5000);
-------------------------------------------------------------------- Create a GeoRaster table (a table that has a
-- column of SDO_GEORASTER object type).
------------------------------------------------------------------create table georaster_table
(georid
number primary key,
type
varchar2(32),
georaster sdo_georaster);
-------------------------------------------------------------------- Create the GeoRaster DML trigger on the GeoRaster table, if
-- the Oracle Database release is before 11.1. (In Release 11.1 and later
-- this trigger is created automatically, so you do not need to create
-- it manually.)
------------------------------------------------------------------call sdo_geor_utl.createDMLTrigger('georaster_table', 'georaster');
-------------------------------------------------------------------- Create a raster data table (RDT).
--- It is used to store cell data of GeoRaster objects.
-- This step is not a requirement. If the RDT table does not
-- exist, the GeoRaster procedures or functions will generate it
-- automatically whenever needed.
-- However, for huge GeoRaster objects, some tuning and setup on those
-- tables can improve the scalability and performance significantly.
-- In those cases, it is better for users to create the RDTs.
-- The primary key must be added to the RDT if you create it.
------------------------------------------------------------------create table rdt_geor of sdo_raster
(primary key (rasterId, pyramidLevel, bandBlockNumber,
rowBlockNumber, columnBlockNumber))
lob(rasterblock) store as (nocache nologging);
commit;
----------------- Import the image.
---------------connect system;
Enter password: password
call dbms_java.grant_permission('MDSYS','SYS:java.io.FilePermission',
'lbs/demo/images/l7_ms.tif', 'read' );
call dbms_java.grant_permission('SCOTT','SYS:java.io.FilePermission',
'lbs/demo/images/l7_ms.tif', 'read' );
connect scott;
Enter password: password
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declare
geor SDO_GEORASTER;
begin
delete from georaster_table where georid = 1;
insert into georaster_table
values( 1, 'TIFF', sdo_geor.init('rdt_geor', 1) );
select georaster into geor
from georaster_table where georid = 1 for update;
sdo_geor.importFrom(geor, '', 'TIFF', 'file',
'lbs/demo/images/l7_ms.tif');
update georaster_table set georaster = geor where georid = 1;
commit;
end;/
connect system;
Enter password: password
call dbms_java.revoke_permission('MDSYS','SYS:java.io.FilePermission',
'lbs/demo/images/l7_ms.tif', 'read' );
call dbms_java.revoke_permission('SCOTT','SYS:java.io.FilePermission',
'lbs/demo/images/l7_ms.tif', 'read' );
connect scott;
Enter password: password
--------------------------- Change the GeoRaster format, if needed.
-- To do this, you can call SDO_GEOR.changeFormatCopy.
-- The following operations for pyramiding, spatial resolution setup, and
-- spatial extent generation can also be combined into one PLSQL block.
-------------------------declare
gr1 sdo_georaster;
begin
--- Using changeFormat with a GeoRaster object:
--- 1. Select the source GeoRaster object.
select georaster into gr1
from georaster_table where georid = 1;
-- 2. Make changes. (Interleaving is application-dependent. For TIFF images,
-the default interleaving is BSQ.)
sdo_geor.changeFormat(gr1, 'blocksize=(512,512,3) interleaving=BIP');
-- 3. Update the GeoRaster object in the GeoRaster table.
update georaster_table set georaster = gr1 where georid = 1;
commit;
end;/
---------------------------- Generate pyramid levels (strongly recommended, but optional).
--------------------------declare
gr sdo_georaster;
begin
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-- 1. Select the source GeoRaster object.
select georaster into gr
from georaster_table where georid = 1 for update;
-- 2. Generate pyramids.
sdo_geor.generatePyramid(gr, 'resampling=NN');
-- 3. Update the original GeoRaster object.
update georaster_table set georaster = gr where georid = 1;
commit;
end;/
------------------------------ Georeference the GeoRaster object.
----------------------------DECLARE
gr sdo_georaster;
BEGIN
SELECT georaster INTO gr FROM georaster_table WHERE georid = 1 FOR UPDATE;
sdo_geor.georeference(gr, 82216, 1,
sdo_number_array(30, 0, 410000.000000),
sdo_number_array(0, -30,3759000.000000));
UPDATE georaster_table SET georaster = gr WHERE georid = 1;
COMMIT;
END;/
------------------------------ Set the spatial resolutions (required for 10gR1 only)
------------------------------ If you are using Oracle Database Release 10.1, set spatial resolutions. (Not
-- required if you are using Release 10.2.) The spatial resolution values of
-- (30, 30) are from the ESRI world file or from the georeferencing information;
-- however, you may have to compute these values if they are not part of
-- the original georeferencing metadata.
DECLARE
gr sdo_georaster;
BEGIN
SELECT georaster INTO gr FROM georaster_table WHERE georid = 1 FOR UPDATE;
sdo_geor.setSpatialResolutions(gr, sdo_number_array(30, 30));
UPDATE georaster_table SET georaster = gr WHERE georid = 1;
COMMIT;
END;
/
------------------------- Update the spatial extent.
-----------------------DECLARE
sptext sdo_geometry;
BEGIN
SELECT sdo_geor.generateSpatialExtent(a.georaster) INTO sptext
FROM georaster_table a WHERE a.georid=1 FOR UPDATE;
UPDATE georaster_table a SET a.georaster.spatialextent = sptext WHERE a.georid=1;
COMMIT;
END;/
commit;
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------------------------------------------------------------------- Create metadata information for the GeoRaster spatial extent column.
-----------------------------------------------------------------INSERT INTO USER_SDO_GEOM_METADATA
VALUES (
'GEORASTER_TABLE',
'georaster.spatialextent',
SDO_DIM_ARRAY(
SDO_DIM_ELEMENT('X', 410000.0, 470000.0, 0.000005),
SDO_DIM_ELEMENT('Y', 3699000.0,3759000., 0.000005)
),
82216 -- SRID
);
------------------------- Create a spatial index on the spatial extent.
-----------------------CREATE INDEX georaster_idx ON georaster_table(georaster.spatialextent)
INDEXTYPE IS MDSYS.SPATIAL_INDEX;
--------------------------------------------------------- Create a predefined GeoRaster theme for the map visualizer.
-------------------------------------------------------INSERT INTO user_sdo_themes VALUES (
'GEORASTER_TABLE',
'GeoTiff image',
'GEORASTER_TABLE',
'GEORASTER',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="georaster" raster_table="RDT_GEOR"
raster_id="1" raster_bands="0,1,2">
</styling_rules>' );
commit;
2.3.4.2 Using Bitmap Masks with GeoRaster Themes
In Oracle Spatial and Graph GeoRaster, bitmap masks can be assigned to GeoRaster
layers stored in the database. A bitmap mask is a special one-bit deep rectangular
raster grid with each pixel having either the value of 0 or 1. It is used to define an
irregularly shaped region inside another image. The 1-bits define the interior of the
region, and the 0-bits define the exterior of the region. For more information about
bitmap masks, see Oracle Spatial and Graph GeoRaster Developer's Guide.
To specify a bitmap mask with a GeoRaster theme, use the <bitmap_masks> element in
the <styling_rules> element for the predefined theme, as shown in Example 2-18.
The <bitmap_masks> element contains one or more <mask> elements, each with a mask
definition for a specific GeoRaster object. In Example 2-18, a mask is defined for
layers 1 and 2 of the GeoRaster object with the raster ID of 1 in the
RDT_MASS_COLOR_MOSAIC table. The <mask> element has the following attributes:
•
raster_id specifies the raster ID value of the GeoRaster object.
•
raster_table specifies the raster data table (RDT).
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•
layers specifies the layer numbers in the GeoRaster object to be used for the
mask.
•
zeromapping specifies the transparency value to be applied during rendering on
bitmap pixels with a value of 0 (zero). The attribute value can be from 0
(completely transparent) to 255 (completely opaque).
•
onemapping specifies the transparency value to be applied during rendering on
bitmap pixels with a value of 1. The attribute value can be from 0 (completely
transparent) to 255 (completely opaque).
Example 2-18
Bitmap Mask in Predefined GeoRaster Theme
<styling_rules theme_type="georaster" raster_id="1"
raster_table="RDT_MASS_COLOR_MOSAIC">
<bitmap_masks>
<mask layers="1,2" zeromapping="0" onemapping="255"/>
</bitmap_masks>
</styling_rules>
2.3.4.3 Reprojection of GeoRaster Themes
Effective with Oracle Spatial and Graph GeoRaster for Release 11.2.0.1, GeoRaster
objects can be reprojected into a different SRID. It is recommended that you apply
Oracle Database patch 10259201, to avoid black boundaries for adjacent reprojected
GeoRaster objects when the objects are rendered in the map visualizer. For more
information, see My Oracle Support document ID 1272931.1, Black Lines After
Reprojection Of Georaster Data Via Wms In Oracle Mapviewer.
In the map visualizer, a GeoRaster theme will be reprojected if its SRID is different
from the map request SRID. The reprojection is just for rendering, with no changes
made to the original GeoRaster object. For older databases without reprojection
support, the GeoRaster object will not be reprojected.
The reprojection modes available are BILINEAR (used as default), NN, CUBIC,
AVERAGE4, AVERAGE16. For more information about reprojection, see Oracle
Spatial and Graph GeoRaster Developer's Guide.
To specify a reprojection mode with a GeoRaster theme, use the reproj_mode keyword
in the <styling_rules> element for the predefined theme, as shown in Example 2-19.
Example 2-19
Reprojection Mode in Predefined GeoRaster Theme
<styling_rules theme_type="georaster" reproj_mode="CUBIC">
</styling_rules>
2.3.4.4 Virtual Mosaic Themes
In Oracle Spatial and Graph GeoRaster, a virtual mosaic is defined as any large
collection of georeferenced GeoRaster objects, rectified or unrectified, from one or
more GeoRaster tables or views that is treated as if it is a single GeoRaster object.
The virtual mosaic can be defined in different ways, like using a single or multiple
GeoRaster tables (or views with a GeoRaster column), and using a full SQL query
statement that results in a collection of GeoRaster objects.
The map visualizer supports the creation of the following types of predefined
GeoRaster virtual mosaic themes:
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•
A theme based on table with a GeoRaster column and possibly containing a query
condition. A list of tables with GeoRaster column can also be defined. The
following XML definition defines a virtual mosaic theme based table
LANDSAT5_IMAGES and GeoRaster column IMAGE:
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="georaster" virtual_mosaic="true">
<virtual_mosaic srid="32617" nodata_cell="true">
<tables>
<table name="LANDSAT5_IMAGES" georaster_column="IMAGE"/>
</tables>
</virtual_mosaic>
</styling_rules>
•
A theme based on a full SQL query. The following XML definition specifies a virtual
mosaic theme based on a SQL query:
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="georaster" virtual_mosaic="true">
<virtual_mosaic srid="32617" nodata_cell="true">
<sql>select image from landsat5_images</sql>
</virtual_mosaic>
</styling_rules>
The following parameters can be defined for a virtual mosaic theme.
srid: The spatial reference system (coordinate system) value.
nodata_cell: Specifies whether or not to consider NODATA (NODATA value or
NODATA bitmap mask) when handling the overlap area. TRUE causes any cell with
NODATA values to be considered as a NODATA cell, and the cell value is not involved
in the overlap area calculation; FALSE causes any cell with NODATA values to be
considered as normal cell, and the cell value is involved in the overlap area
calculation.The default value is FALSE. If the value is TRUE and the resampling method is
BILINEAR, BIQUADRATIC, CUBIC, AVERAGE4, or AVERAGE16, whenever a cell value involved in
the resampling calculation is a NODATA value, the result of the resampling is also a
NODATA value. The resulting NODATA value is the minimum NODATA value
associated with the current raster layer, if multiple NODATA values or value ranges
exist.
common_point_rule: The method for getting the cell value at the overlapping area. Can
have one of the following values:
•
OLDEST: The value from the GeoRaster object that has the oldest EndDataTime in the
metadata is used.
•
END: The value from the last encountered GeoRaster object is used.
•
LATEST: The value from the GeoRaster object that has the most recent EndDataTime
in the metadata is used.
•
OLDEST: The value from the GeoRaster object that has the oldest EndDataTime in the
metadata is used.
•
CTC: The value from the GeoRaster object that is closest to the center of the output
window is used.
•
HIGH: The maximum cell value of all the overlapping GeoRaster objects is used.
•
LOW: The minimum cell value of all the overlapping GeoRaster objects is used
•
AVERAGE: The average of all cell values from the overlapping GeoRaster objects is
used.
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•
HISHRES: The value from the GeoRaster object that has the highest spatial
resolution is used.
resampling_mode: Specifies the resampling method (if resampling is involved or
rectification is needed) to be used during the mosaic operation. Can have one of the
following values: NN, BILINEAR, BIQUADRATIC, CUBIC, AVERAGE4, or AVERAGE16.
resampling_tolerance: Specifies the tolerance for not doing resampling when the
source GeoRaster objects are not perfectly aligned. The value should be between 0
and 0.5, where the unit is pixel or cell (for example, 0.5 meaning one-half pixel or cell).
If not specified, 0.5 is used, which means no resampling will occur.
color_balance: Specifies the method for color balancing. Can have one of the following
values: NONE, LINEARSTRETCHING, NORMALIZATION.
min_stretch_value: Ignored if color_balance is not LINEARSTRETCHING; otherwise,
specifies the lowest value in the range of the linear stretching method. Defaults to 0.
max_stretch_value: Ignored if color_balance is not LINEARSTRETCHING; otherwise,
specifies the highest value in the range of the linear stretching method. Defaults to
255.
mean: Ignored if color_balance is not NORMALIZATION; otherwise, specifies the reference
mean for the normalization method.
standard_deviation: Ignored if color_balance is not NORMALIZATION; otherwise, specifies
the reference standard deviation for the normalization method.
2.3.5 Network Themes
A network theme is a special kind of map visualizer theme useful for visualizing
networks defined using the Oracle Spatial and Graph network data model. A network
consists of a set of nodes and links. A network can be directed or undirected, although
links and paths typically have direction. A network can be organized into different
levels of abstraction, called a network hierarchy. The map visualizer assumes that
network spatial tables in a network use the same coordinate system, and that these
tables are indexed and registered as described in Oracle Spatial and Graph Topology
Data Model and Network Data Model Graph Developer's Guide.
Network node, link, and path tables store geometries of type SDO_GEOMETRY. You
can create JDBC themes that use these geometries. In addition, you can define
dynamic themes that consider aspects of the network, such as the direction of links for
a directed network.
The following elements and attributes apply to the definition of a network theme:
•
<jdbc_network_query> element: Specifies that this is a dynamically defined network
theme.
•
network_name attribute: Specifies the name of the network.
•
network_level attribute (optional): Specifies the network hierarchy level to which
this theme applies. (For a nonhierarchical network, specify 1, which is the default
value.)
•
link_style attribute (optional): Specifies the style name to be used for links.
•
direction_style attribute (optional): Specifies the style name to be used for a link
direction marker (for example, a directional arrow image).
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•
bidirection_style attribute (optional): Specifies the style name to be used for a
bidirected link.
•
direction_position attribute (optional): Specifies the position of the direction
marker relative to the link start, as a number between 0 and 1. For example, 0.85
indicates 85 percent of the way between the link start and end points.
•
direction_markersize attribute (optional): Specifies the size (number of pixels) of
the direction marker.
•
direction_multimarker attribute (optional): Specifies if the direction marker should
be repeated over the link: true repeats the marker at a specified start position and
each subsequent interval of that distance; false (the default) does not repeat the
marker.
•
link_labelstyle attribute (optional): Specifies the style name to be used for link
labels in the column specified in the link_labelcolumn attribute.
•
link_labelcolumn attribute (optional): Specifies the name of the column containing
link labels to be rendered using the style specified in the link_labelstyle attribute.
•
node_style attribute (optional): Specifies the style name to be used for nodes.
•
node_markersize attribute (optional): Specifies the size (number of pixels) of the
node marker.
•
node_labelstyle attribute (optional): Specifies the style name to be used for node
labels in the column specified in the node_labelcolumn attribute.
•
node_labelcolumn attribute (optional): Specifies the name of the column containing
node labels to be rendered using the style specified in the node_labelstyle
attribute.
•
path_ids attribute (optional): Specifies one or more path ID values of stored paths
to be rendered. For more than one path, use commas to delimit the path ID
values. For example, path_ids="1,3,4" specifies that the paths with path ID values
1, 3, and 4 are to be rendered.
•
path_styles attribute (optional): Specifies one or more style names associated with
the paths specified in the path_ids attribute. For example,
path_styles="C.RED,C.GREEN,C.BLUE" specifies styles to be used to render the first,
second, and third paths (respectively) specified in the path_ids attribute.
•
path_labelstyle attribute (optional): Specifies the style name to be used for path
labels in the column specified in the path_labelcolumn attribute.
•
path_labelcolumn attribute (optional): Specifies the name of the column containing
path labels to be rendered using the style specified in the path_labelstyle
attribute.
Additional network theme attributes related to network analysis are described in Using
the Map Visualizer for Network Analysis.
A network theme can combine attributes for links, nodes, and paths, or any
combination. In such cases, the map visualizer first renders the links, then the paths,
and then the nodes.
Example 2-20 defines a network theme that specifies attributes for the display of links
and nodes in the network named NYC_NET.
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Example 2-20
Network Theme
<theme name="net_theme" user_clickable="false">
<jdbc_network_query
network_name="NYC_NET"
network_level="1"
jdbc_srid="8307"
datasource="mvdemo"
link_style="C.RED"
direction_style="M.IMAGE105_BW"
direction_position="0.85"
direction_markersize="8"
node_style="M.STAR"
node_markersize="5"
asis="false">
</jdbc_network_query>
</theme>
•
Creating Predefined Network Themes
•
Using the Map Visualizer for Network Analysis
2.3.5.1 Creating Predefined Network Themes
To create a predefined network theme, you must store the definition of the network
theme in the database by inserting a row into the USER_SDO_THEMES view
(described in xxx_SDO_THEMES Views). Example 2-21 stores the definition of a
network theme.
Example 2-21
Creating a Predefined Network Theme
INSERT INTO user_sdo_themes VALUES (
'NYC_NET_1',
'New York City network',
'NYC_NET_LINK_TABLE',
'GEOMETRY',
'<?xml version="1.0" standalone="yes"?>
<styling_rules
theme_type="network"
network_name="NYC_NET"
network_level="1">
<rule>
<features>
<link
style="C.RED"
direction_style="M.IMAGE105_BW"
direction_position="0.85"
direction_markersize="8">
</link>
<path
ids="1,3"
styles="C.BLUE,C.GREEN">
</path>
<node
style="M.CIRCLE"
markersize="5">
</node>
</features>
<label>
<link column="LINK_ID" style="T.STREET NAME"> 1 </link>
</label>
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</rule>
</styling_rules>' );
Example 2-21 creates a network theme named NYC_NET_1 for level 1 of the network
named NYC_NET. The network table name (NYC_NET_LINK_TABLE in this example) is
inserted in the BASE_TABLE column of the USER_SDO_THEMES view, the link
geometry column name (GEOMETRY in this example) is inserted in the
GEOMETRY_COLUMN column, and an XML document with one <styling_rules>
element is inserted in the STYLING_RULES column.
In the <styling_rules> element for a network theme, theme_type must be network in
order for this theme to be recognized as a network theme. Elements for links, paths,
and nodes can be specified in the same <features> element, as is done in
Example 2-21:
•
The link feature rule specifies the style C.RED and direction marker attributes for all
links.
•
The path feature rule specifies the style C.BLUE for paths with the path ID value 1,
and the style C.GREEN for paths with the path ID value 3.
•
The node feature rule specifies the style M.CIRCLE and a marker size of 5.
Example 2-21 also contains a <label> element for links, specifying the link column
LINK_ID and the label style T.STREET NAME.
The DTD for the <styling_rules> element is presented in Themes: Styling Rules.
2.3.5.2 Using the Map Visualizer for Network Analysis
The network model Java API provides several network analysis capabilities. You can
define map visualizer network themes that support the shortest-path and within-cost
analysis capabilities. Some attributes apply to both capabilities, and some attributes
apply only to the relevant associated capability.
For all network analysis capabilities, the <jdbc_network_query> element and the
network-related attributes described in Network Themes apply to the definition of the
network theme.
For shortest-path analysis, the following attributes apply to the definition of the network
theme:
•
analysis_algorithm attribute: Specifies the shortest-path analysis algorithm to use.
Must be either DIJKSTRA or ASEARCH.
•
shortestpath_style attribute: Specifies the style name to be used for the shortest
path.
•
shortestpath_startnode attribute: Specifies the start node to be used for the
analysis.
•
shortestpath_endnode attribute: Specifies the end node to be used for the analysis.
•
shortestpath_startstyle attribute (optional): Specifies the style name to be used
for the start node.
•
shortestpath_endstyle attribute (optional): Specifies the style name to be used for
the end node.
Example 2-22 defines a network theme that can be used for shortest-path analysis.
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For within-cost analysis, the following attributes apply to the definition of the network
theme:
•
analysis_algorithm attribute: Must be WITHINCOST.
•
withincost_startnode attribute: Specifies the start node to be used for the analysis.
•
withincost_cost attribute: Specifies the cost cutoff value for nodes to be included.
All nodes that can be reached from the start node at a cost less than or equal to
the specified value are included in the resulting display. Nodes that cannot be
reached from the start node or that can be reached only at a cost greater than the
specified value are not included.
•
withincost_startstyle attribute (optional): Specifies the style name to be used for
the start node.
•
withincost_style attribute: Specifies the style name to be used for links in the
displayed paths between the start node and each node that is within the specified
cost cutoff value.
Example 2-23 defines a network theme that can be used for within-cost analysis.
Example 2-22
Network Theme for Shortest-Path Analysis
<theme name="shortest_path_theme" user_clickable="false">
<jdbc_network_query
network_name="BI_TEST"
network_level="1"
jdbc_srid="0"
datasource="mvdemo"
analysis_algorithm="DIJKSTRA"
shortestpath_style="L.PH"
shortestpath_startnode="20"
shortestpath_endnode="101"
shortestpath_startstyle="M.STAR"
shortestpath_endstyle="M.CIRCLE"
asis="false">
</jdbc_network_query>
</theme>
Example 2-23
Network Theme for Within-Cost Analysis
<theme name="within_cost_theme" user_clickable="false">
<jdbc_network_query
network_name="BI_TEST"
network_level="1"
jdbc_srid="0"
datasource="mvdemo"
analysis_algorithm="WITHINCOST"
withincost_startnode="20"
withincost_style="L.PH"
withincost_cost="1"
withincost_startstyle="M.STAR"
asis="false">
</jdbc_network_query>
</theme>
2.3.6 Topology Themes
A topology theme is a special kind of map visualizer theme useful for visualizing
topologies defined using the Oracle Spatial and Graph topology data model. The
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topology data model lets you work with data about nodes, edges, and faces in a
topology. The spatial representations of nodes, edges, and faces are spatial
geometries of type SDO_GEOMETRY. For nodes and edges, the geometries are
explicitly stored; for faces, the initial lines (exterior and interior) are stored, allowing the
face geometry to be generated.
In addition to the spatial representation of nodes, edges, and faces, a topology can
have features. A feature (also called a topology geometry) is a spatial representation
of a real-world object. Each feature is defined as an object of type
SDO_TOPO_GEOMETRY, which identifies the topology geometry type, topology
geometry ID, topology geometry layer ID, and topology ID. For detailed information,
see Oracle Spatial and Graph Topology Data Model and Network Data Model Graph
Developer's Guide.
The map visualizer can render topology features. It can also render a theme in debug
mode (explained later in this section) to show the nodes, edges, and faces of a
topology. For each topology theme, the map visualizer uses the topology metadata
information stored in the USER_SDO_TOPO_METADATA view.
The following elements and attributes apply to the definition of a topology theme:
•
<jdbc_topology_query> element: Specifies that this is a dynamically defined
topology theme. The element can specify a SQL query statement (without a
terminating semicolon).
•
topology_name attribute: Specifies the name of the topology.
•
feature_table attribute: Specifies the name of the feature table.
•
spatial_column attribute: Specifies the name of the spatial feature column of type
SDO_TOPO_GEOMETRY.
•
label_column attribute: Specifies the column in the feature table that contains the
text label to be used with each feature.
•
label_style attribute: Specifies the name of the text style to be used to render the
labels in the label column.
•
render_style attribute: Specifies the name of the style to be used to render the
topology.
Example 2-24 defines a topology theme that specifies attributes for the display of
features and labels from the LAND_PARCELS table in the CITY_DATA topology. The
SQL statement specifies the spatial feature column and the label column, and it
includes all rows in the feature table.
The map visualizer also supports a debug mode that renders the nodes, edges, and
faces of a topology. To specify debug mode, include the mode="debug" attribute in the
<theme> element. In addition to the <jdbc_topology_query> attributes mentioned earlier
in this section, the following attributes can be used in debug mode:
•
edge_style attribute: Specifies the name of the style to be used to render edges.
•
edge_label_style attribute: Specifies the name of the text style to be used to
render edge labels.
•
edge_marker_style attribute: Specifies the name of the marker style to be used for
edge markers.
•
edge_marker_size attribute: Specifies the size (number of pixels) of for edge
markers.
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•
node_style attribute: Specifies the name of the style to be used to render nodes.
•
node_label_style attribute: Specifies the name of the text style to be used to
render node labels.
•
face_style attribute: Specifies the name of the style to be used to render faces.
•
face_label_style attribute: Specifies the name of the text style to be used to
render face labels.
Example 2-25 defines a debug-mode topology theme for rendering features, edges,
nodes, and faces from all feature tables in the CITY_DATA topology.
Example 2-24
Topology Theme
<theme name="topo_theme" user_clickable="false">
<jdbc_topology_query
topology_name="CITY_DATA"
feature_table="LAND_PARCELS"
label_column="FEATURE_NAME"
spatial_column="FEATURE"
label_style="T.CITY NAME"
render_style="C.COUNTIES"
jdbc_srid="0"
datasource="topology"
asis="false">select feature, feature_name from land_parcels
</jdbc_topology_query>
</theme>
Example 2-25
Topology Theme Using Debug Mode
<theme name="topo_theme" mode="debug" user_clickable="false">
<jdbc_topology_query
topology_name="CITY_DATA"
edge_style="C.RED"
edge_marker_style="M.IMAGE105_BW"
edge_marker_size="8"
edge_label_style="T.EDGE"
node_style="M.CIRCLE"
node_label_style="T.NODE"
face_style="C.BLUE"
face_label_style="T.FACE"
jdbc_srid="0"
datasource="topology"
asis="false">
</jdbc_topology_query>
</theme>
•
Creating Predefined Topology Themes
2.3.6.1 Creating Predefined Topology Themes
To create a predefined topology theme, you must store the definition of the topology
theme in the database by inserting a row into the USER_SDO_THEMES view
(described in xxx_SDO_THEMES Views). Example 2-26 stores the definition of a
topology theme.
Example 2-26 creates a topology theme named LANDPARCELS for the topology named
CITY_DATA. The feature table name (LAND_PARCELS in this example) is inserted in
the BASE_TABLE column of the USER_SDO_THEMES view, the feature column
name (FEATURE in this example) is inserted in the GEOMETRY_COLUMN column,
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and an XML document with one <styling_rules> element is inserted in the
STYLING_RULES column.
In the <styling_rules> element for a topology theme, theme_type must be topology in
order for this theme to be recognized as a topology theme. The theme in
Example 2-26 defines one styling rule that renders all land parcel features from the
CITY_DATA topology using the C.RED style and using the T.TEXT STYLE label style for
values in the FEATURE_NAME column of the feature table.
The DTD for the <styling_rules> element is presented in Themes: Styling Rules.
Example 2-26
Creating a Predefined Topology Theme
INSERT INTO user_sdo_themes VALUES (
'LANDPARCELS',
'Topology theme for land parcels',
'LAND_PARCELS',
'FEATURE',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="topology" topology_name="CITY_DATA">
<rule>
<features style="C.RED"></features>
<label column="FEATURE_NAME" style="T.TEXT STYLE"> </label>
</rule>
</styling_rules>' );
2.3.7 WFS Themes
A WFS theme is a special kind of map visualizer theme that supports the rendering of
data delivered using the Open GIS Consortium (OGC) Web Feature Service (WFS)
protocol, specifically the WFS 1.0.0 implementation specification.
WFS theme are conceptually similar to geometry themes, and users are able to render
and label features. The WFS operations GetCapabilities, DescribeFeatureType, and
GetFeature are used when rendering a WFS theme. When a WFS service is accessed,
the map visualizer caches the information about capabilities and feature types.
•
GetCapabilities retrieves the server general information, including the URL
addresses to issue requests and the features available. In general, a WFS
capability request has the form:
http://localhost:1979/geoserver/wfs/GetCapabilities?
SERVICE=WFS&VERSION=1.0.0&REQUEST=GetCapabilities
The result includes a <Capabilities> element with the URL addresses for the WFS
requests. For example, the following includes the GetCapabilities URLs for HTTP
GET and POST requests.
<Capability>
<Request>
<GetCapabilities>
<DCPType>
<HTTP>
<Get onlineResource="http://localhost:1979/geoserver/wfs/
GetCapabilities?" />
</HTTP>
</DCPType>
<DCPType>
<HTTP>
<Post onlineResource="http://localhost:1979/geoserver/wfs/
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GetCapabilities?" />
</HTTP>
</DCPType>
</GetCapabilities>
. . .
</Capability>
•
DescribeFeatureType retrieves the feature information, including attributes and
types.
•
GetFeature retrieves the feature geometries and attributes. The output format for
GetFeature requests is GML2.
The following attributes apply to the definition of a WFS theme:
•
datasource attribute: Specifies the map visualizer data source from which styles
will be loaded.
•
feature_attributes attribute: Specifies feature attributes (besides geometry and
label columns) that can be used with advanced styles.
•
feature_ids attribute: Specifies the WFS feature IDs to be retrieved. Feature IDs
are represented with the fid name in the WFS responses. If feature IDs are
specified, spatial filter and query conditions are not used in the WFS request.
•
feature_name attribute: Specifies the WFS feature name.
•
key_column attribute: Specifies the attribute to be used as a key column. Applies to
predefined themes, and can be used in Oracle Maps applications. If key_column is
not specified, fid is used as the key column.
•
label_column attribute: Specifies the column in the feature table that contains the
text label to be used with each WFS feature.
•
label_style attribute: Specifies the name of the text style to be used to render the
labels in the label column.
•
query_condition attribute: Specifies a WHERE clause condition to be applied to the
WFS theme. Cannot be a complex condition with a hierarchy of expressions
defined using multiple parentheses. Each string in the query must be separated by
a blank space. If the condition cannot be parsed, it is ignored on the WFS request.
Any query conditions are ignored if you specify the feature_ids attribute. The
following are examples of valid expressions:
state_name = 'New Hampshire' or state_name = 'New York'
(state_name = 'New Hampshire' or state_name = 'New York') and top_pop > 700000
(state_name = 'New Hampshire' or state_name = 'New York') and (top_pop > 700000)
•
render_style attribute: Specifies the name of the style to be used to render the
geometry.
•
service_url attribute: Corresponds to the capabilities address for HTTP GET
requests. The service_url parameter for the map visualizer must be the online
resource address for HTTP GET in the <GetCapabilities> element. In the preceding
example, the value to be used is: http://localhost:1979/geoserver/wfs/
GetCapabilities?
Do not include the Capabilities parameters SERVICE, VERSION, and REQUEST; use just
the URL from the capabilities information.
•
spatial_column attribute: Specifies the name of the spatial feature column of type
SDO_TOPO_GEOMETRY.
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•
srs attribute: Specifies the spatial reference system (coordinate system) name for
the WFS feature, in EPSG or Oracle Spatial and Graph format. For example, EPSG:
4325, SDO:8307, and 8307 (the Spatial and Graph SRID value) specify the same
SRS. If an EPSG SRS value is specified, the map visualizer tries to identify an
equivalent Spatial and Graph (SDO) SRID; and if no matching SRID is found, the
SRID for the theme is assumed to be zero (0). The map visualizer looks for
matching SRID values as follows:
•
1.
Use any custom mapping specified in an SDO to EPSG SRID mapping file
specified map visualizer configuration file, as explained inCustomizing SRS
Mapping.
2.
Use the Spatial and Graph function
SDO_CS.MAP_EPSG_SRID_TO_ORACLE to get the equivalent SDO code (if
this function is available in the version of Oracle Database used to store the
data).
3.
Use the EPSG code that is in the MDSYS.CS_SRS table, if a match can be
found.
user and password attributes can be defined to access a secured WFS server that
uses basic authentication.
If the WFS server is deployed in WebLogic Application Server, the parameter DUseSunHttpHandler=true must be added to the startup script of WebLogic server.
Example 2-27 shows a request with a dynamic WFS theme. The WFS service is
geoserver, and it is installed on the local system.
Example 2-27
WFS Request with a Dynamic WFS Theme
<?xml version="1.0" standalone="yes"?>
<map_request
title="WFS MAP"
datasource = "mvdemo"
width="640"
height="480"
bgcolor="#a6cae0"
antialiase="true"
mapfilename="wfs_map"
format="PNG_URL">
<center size="20.">
<geoFeature >
<geometricProperty typeName="center">
<Point>
<coordinates>-70., 44.</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="wfs" >
<wfs_feature_request
service_url="http://localhost:1979/geoserver/wfs/GetCapabilities?"
srs="EPSG:4326"
feature_name="states"
spatial_column="the_geom"
render_style="C.COUNTIES"
label_column="STATE_NAME"
label_style="T.STATE NAME"
datasource="mvdemo" />
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</theme>
</themes>
</map_request>
•
Creating Predefined WFS Themes
2.3.7.1 Creating Predefined WFS Themes
To create a predefined WFS theme, you must store the definition of the WFS theme in
the database by inserting a row into the USER_SDO_THEMES view (described in
xxx_SDO_THEMES Views). Example 2-28 stores the definition of a WFS theme.
In Example 2-28, the WFS feature POI is used as the base table, and the attribute
THE_GEOM is the spatial column. The styling rule information contains the service_url
and srs information; and although not shown inExample 2-28, it can also specify a
key_column value. The <features> and <label> elements of the styling rules are similar
to the rules used in geometry themes. Hidden information (<hidden_info> element) can
also be defined and used in Oracle Maps applications.
Example 2-29 shows a map request that uses the predefined theme created in
Example 2-28.
In some cases, proxy information may affect the access to WFS servers. If this occurs,
specify the appropriate proxy parameters in the map visualizer configuration file.
Example 2-28
Creating a Predefined WFS Theme
INSERT INTO user_sdo_themes VALUES (
'WFS_THEME1',
'WFS',
'POI',
'THE_GEOM',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="wfs" service_url="http://localhost:1979/geoserver/wfs/
GetCapabilities?" srs="EPSG:4326">
<hidden_info>
<field column="NAME" name="name"/>
<field column="MAINPAGE" name="mainpage"/>
</hidden_info>
<rule>
<features style="M.STAR"> </features>
<label column="NAME" style="T.STREET NAME"> 1 </label>
</rule>
</styling_rules>' );
Example 2-29
Map Request with Predefined WFS Theme
<?xml version="1.0" standalone="yes"?>
<map_request
title="Predefined WFS MAP"
datasource = "mvdemo"
width="640"
height="480"
bgcolor="#a6cae0"
antialiase="true"
format="PNG_STREAM">
<themes>
<theme name="wfs_theme1" />
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</themes>
</map_request>
2.3.8 WMTS Themes
A WMTS theme supports the rendering of data delivered using the Open GIS
Consortium (OGC) Web Map Tile Service (WMTS) standard, specifically the WMTS
1.0.0 implementation standard.
A WMTS theme fetches tile images from a WMTS-enabled server over the Internet
and renders the images. The tile images on a WMTS-enabled server are spatially
referenced with predefined content, extent, and resolution.
The WMTS operations GetCapabilities, GetTile, and GetFeatureInfo are used when
rendering a WMTS theme. When a WMTS service is accessed by the map visualizer,
it caches the capabilities information of that WMTS service. You may need to specify a
proxy server in Map Builder when creating a WMTS theme and to edit the map
visualizer configuration file (MapViewerConfig.xml) when a WMTS theme is being used.
•
A GetCapabilities operation retrieves the server's general information, including
the URL addresses to issue requests and the features available. In general, a
WMTS capability request has the form:
http://maps.opengeo.org/geowebcache/service/wmts?
service=WMTS&version=1.0.0&request=GetCapabilities
The result includes a <Capabilities> element with the URL addresses for the
WMTS requests. For example, the following includes the GetCapabilities URLs for
HTTP GET or POST requests:
<?xml version="1.0" encoding="UTF-8"?>
<Capabilities xmlns="http://www.opengis.net/wmts/1.0"
xmlns:ows="http://www.opengis.net/ows/1.1"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:gml="http://www.opengis.net/gml" xsi:schemaLocation="http://
www.opengis.net/wmts/1.0 http://schemas.opengis.net/wmts/1.0/
wmtsGetCapabilities_response.xsd"
version="1.0.0">
<ows:ServiceIdentification>
<ows:Title>Web Map Tile Service - GeoWebCache</ows:Title>
<ows:ServiceType>OGC WMTS</ows:ServiceType>
<ows:ServiceTypeVersion>1.0.0</ows:ServiceTypeVersion>
</ows:ServiceIdentification>
<ows:ServiceProvider>
<ows:ProviderName>http://maps.opengeo.org/geowebcache/service/wmts</
ows:ProviderName>
<ows:ProviderSite xlink:href="http://maps.opengeo.org/geowebcache/service/
wmts" />
<ows:ServiceContact>
<ows:IndividualName>GeoWebCache User</ows:IndividualName>
</ows:ServiceContact>
</ows:ServiceProvider>
<ows:OperationsMetadata>
<ows:Operation name="GetCapabilities">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://maps.opengeo.org/geowebcache/service/wmts?">
<ows:Constraint name="GetEncoding">
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<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
<ows:Operation name="GetTile">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://maps.opengeo.org/geowebcache/service/wmts?">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
<ows:Operation name="GetFeatureInfo">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://maps.opengeo.org/geowebcache/service/wmts?">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
</ows:OperationsMetadata>
<Contents>
<Layer>
<ows:Title>bluemarble</ows:Title>
<ows:WGS84BoundingBox>
<ows:LowerCorner>-180.0 -90.0</ows:LowerCorner>
<ows:UpperCorner>180.0 90.0</ows:UpperCorner>
</ows:WGS84BoundingBox>
<ows:Identifier>bluemarble</ows:Identifier>
<Style isDefault="true">
<ows:Identifier>_null</ows:Identifier>
</Style>
<Format>image/png</Format>
<Format>image/jpeg</Format>
<TileMatrixSetLink>
<TileMatrixSet>EPSG:4326</TileMatrixSet>
</TileMatrixSetLink>
<TileMatrixSetLink>
<TileMatrixSet>EPSG:900913</TileMatrixSet>
</TileMatrixSetLink>
</Layer>
...
<TileMatrixSet>
<ows:Identifier>EPSG:4326</ows:Identifier>
<ows:SupportedCRS>urn:ogc:def:crs:EPSG::4326</ows:SupportedCRS>
<TileMatrix>
<ows:Identifier>EPSG:4326:0</ows:Identifier>
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<ScaleDenominator>2.795411320143589E8</ScaleDenominator>
<TopLeftCorner>90.0 -180.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>2</MatrixWidth>
<MatrixHeight>1</MatrixHeight>
</TileMatrix>
...
</TileMatrixSet>
...
</Contents>
<ServiceMetadataURL xlink:href="http://maps.opengeo.org/geowebcache/service/wmts?
REQUEST=getcapabilities&amp;VERSION=1.0.0"/>
</Capabilities>
•
A GetTile operation retrieves a tile image from a WMTS server. A request to the
server contains parameters of key-value pairs (KVP) that define the tile image.
•
A GetFeatureInfo operation allows WMTS clients to request information at a
specific position of a specific tile for a specific query layer.
Detailed descriptions of these operations can be found at http://
www.opengeospatial.org/standards/wmts.
The following attributes apply to the definition of a WMTS theme:
•
current_threads attribute (optional): an integer (int) variable; the default is 8. It is
the number of concurrent threads for retrieving tile images from a WMTS server. In
general, a larger number of concurrent threads allows more threads to retrieve
image tiles in parallel from a map server. Other constraining factors may prevent
you from using a number in the hundreds, but you may try to set it 16, 32, or a
slightly larger value for faster processing.
•
format attribute: Specifies the tile image formats stored in the WMTS server. The
tif, jpeg, png, and png8 formats are supported in the map visualizer.
•
layer attribute: Specifies the layer name for which the tile images are to be
fetched.
•
matrix_set_id attribute: Specifies the ID of the matrix set from which the tile
images are to be fetched.
•
service_url attribute: Corresponds to the capabilities address for HTTP GET
requests. The service_url parameter for the map visualizer must be the online
resource address for HTTP GET in the <GetCapabilities> element. In the
preceding example, the value to be used is: http://maps.opengeo.org/geowebcache/
service/wmts?
•
snap_to_tile_scale attribute (optional): a Boolean value (true or false); the default
is false.
When snap_to_tile_scale is set to true, a request scale (derived from a devicewindow size and a request-data-window size) is snapped to a closest tile scale;
the map scale will be in the tile scale. For example, if there are tiles in scale series
of …, 1:4000, 1:2000, 1.1000, 1:500, …., a request scale of 1:1600 will be
snapped to the 1:2000 tile scale, and the map will be using the same 1:2000 scale,
as shown in Figure 2-9.
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Figure 2-9
snap_to_tile_scale Attribute
If a map request has more than one WMTS theme that specifies
snap_to_tile_scale as true, then only the first WMTS snap_to_tile_scale
specification is set to true and all others are reset to false. This is the logical
behavior. For example, if two such themes both have the attribute set to true, but
the two WMTS tile scale series are different from each other (the two map servers
may be from different institutions using different scale series), the first theme will
then use its closest tile scale to retrieve tile data and for the final request scale; at
the same time, the second theme has to reset its snap_to_tile_scale to false, then
has to find its own tile scale according to its tile_resizing_option, then retrieve
tiles, and finally resize the tiles to match the first theme's tile scale.
•
style attribute: Currently not used in the map visualizer; the default is the string
default.
•
tile_resizing_option attribute (optional): the string unbiased, expand_biased, or
contract_biased; the default is unbiased. If snap_to_tile_scale is set to true,
tile_resizing_option is ignored.
For more information, see How the tile_resizing_option Attribute Works.
•
timeout attribute (optional): an integer specifying a request's timeout period in
milliseconds; the default is 0, (that is, no limit for a request to wait for a response).
Specifying this attribute ensures that a map request is terminated when the map
server does not respond within the specified time period, and thus frees the
resources. You might try a value of 30000 (30,000 milliseconds, or 30 seconds).
•
top_left_corner_x attribute (optional): the x coordinate value of the top left corner
of the whole tile images' extent that is served by a WMTS server. If not specified,
the value retrieved from the WMTS server is used. If you specify this attribute, also
specify the top_left_corner_y attribute.
•
top_left_corner_y attribute (optional): the y coordinate value of the top left corner
of the whole tile images' extent that is served by a WMTS server. If not specified,
the value retrieved from the WMTS server is used. If you specify this attribute, also
specify the top_left_corner_x attribute.
•
version attribute: the version of the WMTS specification implemented by the
WMTS server.
•
How the tile_resizing_option Attribute Works
•
snap_to_tile_scale and tile_resizing_option Attribute Usage Guidelines
•
Creating Predefined WMTS Themes
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See Also:
OGC WMTS Support in the Map Visualization Component for information
about the WMTS service for map visualizer, WMTS Operations, and preparing
the WMTS service for the map visualizer.
2.3.8.1 How the tile_resizing_option Attribute Works
If a WMTS theme's snap_to_tile_scale attribute is false (the default) or omitted, a
request scale is always honored and the tile_resizing_option attribute value
(specified or defaulted) is used when choosing a proper tile scale. However, if
snap_to_tile_scale is true, the tile_resizing_option attribute value is ignored.
The tile_resizing_option attribute value can be one of the following string values:
string unbiased (the default), expand_biased, or contract_biased.
•
unbiased (the default): The closest tile scale level is chosen, and then the tile
images are expanded or contracted to generate a map in the request scale. For
example, in Figure 2-10 the tile scale 1:2000 is used to generate any request scale
map if a request scale falls within a scale range of 1:3000 and 1:1500.
Figure 2-10
•
unbiased tile_resizing_option Value
expand_biased: When identifying a proper tile scale to generate a map in a request
scale, a preference for expanding tile images to render a request map is used. In
other words, you prefer to use a smaller tile scale to generate a map for a request
scale. An 8:2 preference ratio for expanding is currently implemented. For
example, in Figure 2-11 the tile scale 1:2000 is used for generating a request map
if its scale is in the range of 1:2400 to 1:1200.
Figure 2-11
•
expand_biased tile_resizing_option Value
contract_biased: When identifying a proper tile scale to generate a map in request
scale, a preference for contracting tiles to render a request map is used. In other
words, you prefer to use a larger tile scale to generate a map for a request scale.
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An 8:2 preference ratio for contracting is currently implemented. For example, in
Figure 2-12 the tile scale 1:2000 is used for generating a request map if its scale is
in the range of 1:3600 to 1:1800.
Figure 2-12
contract_biased tile_resizing_option Value
See also snap_to_tile_scale and tile_resizing_option Attribute Usage Guidelines.
2.3.8.2 snap_to_tile_scale and tile_resizing_option Attribute Usage Guidelines
This section presents general guidelines for using the snap_to_tile_scale and
tile_resizing_option attributes to generate better quality maps. Because mapping has
a wide variety of applications, you may also use your domain knowledge to set
attribute values that best meet your needs.
Whenever possible, set snap_to_tile_scale to true to use a closest tile scale instead of
a request scale, because original tile maps have the best map quality.
However, if you must honor a request scale, consider the following when setting the
attributes:
•
If you set a tile_resizing_option value, omit the snap_to_tile_scale attribute or set
it to false (the default). If snap_to_tile_scale is set to true, a request scale will not
be honored, and instead the closest tile scale will be used.
•
If a map is a topographic map with annotations and thin linear features, you may
want to use the expand_biased option.
•
If a map is a thematic map, such as a land cover map, you may want to use the
contract_biased option.
•
If a map is a satellite image, you may want to use the unbiased or contract_biased
option.
Regarding the tile_resizing_option possible values:
•
In general, a contract_biased option may generate maps with more details, but
these maps may need more tiles than maps from an expand_biased option, and
retrieving more tiles takes more time.
•
If a request scale is honored (when the snap_to_tile_scale attribute is set to
false), when a request scale is close enough to a tile scale, then the same
operation will be employed (either expanding or contracting), regardless of the
specified tile_resizing_option. For example, if a request scale is 1:1900 in the
figures in How the tile_resizing_option Attribute Works, tile maps in 1:2000 will be
retrieved and expanded to render the request map in a map scale of 1:1900,
regardless of whether the unbiased, expand_biased, or contract_biased option is
specified; similarly, if a request scale is 1:2100, then tile maps in 1:2000 will also
be retrieved and then contracted to render the requested map in a scale of 1:2100.
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Example 2-30 shows a request with a dynamic WMTS theme, in which
snap_to_tile_scale="true" is specified.
Example 2-30
Request with a Dynamic WMTS Theme
<?xml version="1.0" standalone="yes"?>
<map_request title="OpenGeo wmts theme (bluemarble)"
datasource="mvdemo"
width="1024"
height="900"
mapfilename="Bluemarble"
format="PNG_STREAM">
<center size="80.0">
<geoFeature>
<geometricProperty typeName="center">
<Point>
<coordinates>-112, 42.0</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="wmtstheme: Earth" timeout="10000" snap_to_tile_scale="true">
<wmts_gettile_request>
<service_url> http://maps.opengeo.org/geowebcache/service/wmts </service_url>
<version> 1.0.0 </version>
<layer> bluemarble </layer>
<matrix_set_id> EPSG:4326 </matrix_set_id>
<format> image/png </format>
<style> default </style>
<top_left_corner_x> -180.0 </top_left_corner_x>
<top_left_corner_y> 90.0 </top_left_corner_y>
</wmts_gettile_request>
</theme></themes>
</map_request>
2.3.8.3 Creating Predefined WMTS Themes
To create a predefined WMTS theme, you must store the definition of the WMTS
theme in the database by inserting a row into the USER_SDO_THEMES view
(described in xxx_SDO_THEMES Views). Example 2-31 stores the definition of a
WMTS theme.
In Example 2-31, earth_image is the name of the WMTS theme, and table_spaceholder
and geom_col_spaceholder are dummy values to fill the BASE_TABLE and
GEOMETRY_COLUMN columns in the USER_SDO_THEMES view. The styling rule
information contains the service_url, layer, matrix_set_id, format, and style
information. The top_left_corner_x and top_left_corner_y attributes are not specified,
so by default the values retrieved from the WMTS server are used.
Example 2-32 shows a map request that uses the predefined theme created in
Example 2-31.
Example 2-31
Creating a Predefined WMTS Theme
INSERT INTO user_sdo_themes VALUES (
'earth_image',
'Opengeo.org demo',
'table_spaceholder',
'geom_col_spaceholder',
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'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="wmts">
<version> 1.0.0 </version>
<service_url> http://maps.opengeo.org/geowebcache/service/wmts </service_url>
<layer> bluemarble </layer>
<matrix_set_id> EPSG:4326 </matrix_set_id>
<format> image/png </format>
<style> default </style>
</styling_rules>');
Example 2-32
Map Request with Predefined WMTS Theme
<?xml version="1.0" standalone="yes"?>
<map_request
title="OpenGeo predefined wmts theme"
datasource="mvdemo"
width="1024"
height="768" mapfilename="Bluemarle: Earth"
format="PNG_STREAM">
<center size="10.0">
<geoFeature>
<geometricProperty typeName="center">
<Point>
<coordinates>-75.0,42.0</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="earth_image" />
</themes>
</map_request>
2.3.9 Custom Geometry Themes
Custom geometry themes are associated with external spatial data (spatial data in a
native format other than Oracle Spatial and Graph, such as shapefile). A custom
geometry theme uses a spatial provider class to retrieve the native data, and the
external provider must use the spatial data provider plug-in mechanism. The map
visualizer provides a spatial provider interface class that the external provider must
implement. The interface implementation has the following methods (some of them
mainly provide information that can be used in user interfaces of applications like Map
Builder):
public interface SDataProvider
{
/**
* Returns the initialization parameters for the provider.
* @return String[] - array with initialization parameter names
*/
public String[] getInitParameterNames();
/**
* Returns runtime parameter names. Runtime parameters are additional parameters
* that the provider may use when retrieving the data objects.
* @return String[] - array with runtime parameter names
*/
public String[] getRuntimeParameterNames();
/**
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* Returns a value that gives a hint for the runtime parameter value.
* This hin can be used as a tooltip in user intefaces.
* @param runtimeParam
* @return a String representing the hint value, or null if no hint is available
*/
public String getRuntimeParameterHintValue(String runtimeParam);
/**
* This method is used to set the initialization parameters for the specific
* data provider.
* @param params - parameters to be used by the initialization method.
* @return boolean - true if success; false otherwise
*/
public boolean init(Properties params);
/**
* This method creates and returns an instance of SDataSet which contains
* all the Spatial data produced by this provider, based on
* the given parameters for a specific incoming map request.
* <br>
* The map visualizer calls this method on the custom theme producer
implementation.
*
* @param queryWin the search area to retrieve spatial objects. The window is
* assumed to be already on data provider spatial reference system.
* @param nonSpatialColumns - the list of attributes that will return with objects.
* @param queryCondition - query condition expression (may have binding
parameters).
* @param bindingParameters - binding variables for query condition with binding
parameters.
* @param params - parameters that the provider may use to retrieve the data.
* @return SDataObject - an instance of SDataSet class; null if failed.
*/
public SDataSet buildDataSet(Rectangle2D queryWin,String []nonSpatialColumns,
String queryCondition,Object[] bindingParameters,
Properties params);
/**
* Returns the list of existing attributes for this data provider.
* @param params parameters that the provider may use to get the attribute list.
* @return Field[] - array of attributes for this provider.
*/
public Field[] getAttributeList(Properties params);
/**
* Returns the data set spatial extent MBR.
* @param params parameters that the provider may use to get the data extents
* @return Rectangle2D - data spatial extent for this provider.
*/
public Rectangle2D getDataExtents(Properties params);
/**
* Returns if provider can build spatial indexes.
* If true, means that buildSpatialIndex method can be called.
* @return
*/
public boolean canBuildSpatialIndex();
/**
* Builds a spatial index on the data set.
* @param params parameters that the provider may use to build the spatial index.
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* @return boolean - true if saptial index creation is successful.
*/
public boolean buildSpatialIndex(Properties params);
/**
* Clears provider internal caches (if provider implement caches).
*/
public void clearCache();
/**
* Returns the parameter names that can be used to query for spatial tables.
* Can be used more as information for user interfaces.
* @return
*/
public String[] getParametersToQuerySpatialMetadata();
/**
* Returns the spatial tables and spatial columns.
* @param params must define the parameters returned from
* getParametersToQuerySpatialMetadata.
* @return an array list defining the table name(index [0])
*
and spatial column (index[1])
*/
public String[][] getSpatialTables(Properties params);
}
The init and buildDataSet methods must be implemented. The other method
implementations can be empty; however applications (such as the Oracle Map Builder
Tool) can make use of these methods to handle the information about spatial data
providers. A provider can implement its own spatial indexing mechanism; the map
visualizer offers an implementation for the shapefile provider, and the
buildSpatialIndex method creates an indexing file with the .oix extension in the
shapefile directory. Creating and Registering a Custom Spatial Data Provider contains
an example of how to implement and register a sample spatial provider with the map
visualizer.
To render native data in the map visualizer with custom geometry themes, follow these
steps:
1.
Implement a spatial provider class based on the plug-in interface, and generate a
jar file with the provider implementation. Copy the jar file to a directory that is part
of the map visualizer CLASSPATH definition.
2.
Register the provider in the map visualizer configuration. The map visualizer ships
with a shapefile provider to access ESRI shapefiles, a GDAL-OGR provider to
access data formats supported by OGR, and a Teradata provider to access data
stored in a Teradata database. (See the GDAL-OGR and Teradata documentation
for detailed information about handling spatial data in these environments.) The
GDAL-OGR library gdal.jar, and Teradata libraries terajdbc4.jar and
tdgssconfig.jar, must be on server classpath. The registration section in the map
visualizer configuration file looks like this:
<s_data_provider
id="shapefileSDP"
class="oracle.sdovis.ShapefileDataProvider"
>
<parameters>
<parameter name="datadir" value="/temp/data" />
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</parameters>
</s_data_provider>
Each provider must have id and class names defined: id is a unique name that
identifies the provider, and class corresponds to the Java class implementation.
The <parameters> element defines the initialization parameters of the provider.
For the shapefile provider, the initialization parameter datadir defines where the
map visualizer will look for the data files, and thus it should be a directory that is
accessible to the map visualizer. The map visualizer first looks for data files based
on the theme definition information; and if the data path defined in the theme
definition is not accessible, the map visualizer looks for the data path defined in
the configuration file.
3.
Create custom geometry themes associated with the external spatial data
provider.
Example 2-33
Defining a Dynamic Custom Geometry Theme
<theme name="custom_geom_theme_1" >
<custom_geom_theme
provider_id="shapefileSDP"
srid="26986"
render_style="C.RED"
label_column="parcel_id"
label_style="T.CITY NAME"
datasource="mvdemo">
<parameters>
<parameter name="filename" value="/lbs/demo/shapefile/parcel.shp"/>
</parameters>
</custom_geom_theme>
</theme>
Example 2-34
Storing a Predefined Custom Geometry Theme
insert into user_sdo_themes values (
'SHAPE_THEME',
'Shapefile theme',
'CUSTOM_TABLE',
'GEOMETRY',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="geom_custom" srid="26986" provider_id="shapefileSDP">
<rule>
<features style="C.RED"> </features>
<label column="PARCEL_ID" style="T.CITY NAME"> 1 </label>
</rule>
<parameters>
<parameter name="filename" value="/lbs/demo/shapefile/parcel.shp"/>
</parameters>
</styling_rules>'
);
Although the external spatial data is outside the Oracle database, you still need to
have a database connection to render this data. The database is used to store the
metadata information related with the theme, as well as the styling information used to
render and to label the data.
Example 2-33 shows the definition for a dynamic custom geometry theme. The XML
element <custom_geom_theme> identifies a custom geometry theme. The <parameters>
element defines the runtime parameters to be used by the provider. In this case
"filename" is a runtime parameter, and "/lbs/demo/shapefile/parcel.shp" defines the
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file path. The map visualizer first attempts to use this file path definition; but if it is not
accessible, it uses the data directory value defined in the configuration file for the
shapefile spatial provider.
The runtime parameters for the available spatial providers are as follows (note that
Map Builder provides the option to encrypt parameter values):
•
For a shapefile provider:
–
•
filename: full path to the shapefile (.shp) on disk
For GDAL-OGR:
–
datasource: a full OGR data source string. Depending on the data source
format, this string can vary.(see the GDAL-OGR documentation for detailed
information about connecting to different formats supported by GDAL-OGR.)
For file formats, this parameter's value is usually the full path to the archive.
For database connections, enter the full connection string to access the spatial
table and spatial column. For example, for a Postgis table name STATES with
one spatial column, the value might be:
datasource = PG:dbname='template_postgis' host='localhost' port='5432'
user='postgres' password='manager' tables=states
•
For a Teradata provider:
–
jdbcurl: the JDBC connection to Teradata database. The string format is:
jdbc:teradata://<host_address>/
DATABASE=<db_name>,DBS_PORT=<db_port>,TMODE=ANSI,CHARSET=UTF8
–
user: database user.
–
password: database password.
–
containerds: Optional. Name of Teradata container data source defined on the
application server (WebLogic, for example). If defined, this will be used first in
the map visualizer, instead of the jdbcurl value.
–
basetable: name of the spatial table.
–
geomcolumn: name of the spatial column.
–
fetchsize: Optional. Number of rows to be prefetched.
The available attributes for a dynamic custom geometry theme are:
•
provider_id specifies the spatial provider.
•
datasource specifies the Oracle database connection. This connection is used to
retrieve the styles to render the spatial data.
•
srid specifies the spatial reference system (Oracle Spatial and Graph coordinate
system).
•
render_style specifies the style to be used when rendering the features.
•
label_column specifies the name of the column containing label text to be used with
the theme.
•
label_style specifies the style to be used when labeling the features.
•
feature_attributes specifies additional attributes that can be used with advanced
styles.
•
key_column specifies a key attribute that can be used in Oracle Maps applications.
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•
query_condition specifies the WHERE clause to filter feature selection. Shapefile
providers do not support a query condition; however an OGR provider can be used
to render shapefiles with a query condition. The query condition expression can
define binding parameters (for example, attr = :1).
Example 2-34 shows how to store a predefined custom geometry theme definition.
Use GEOMETRY as the geometry column name, and you can specify any name for
the base table name. The "theme_type=geom_custom" attribute identifies the theme as a
custom theme. The <rule> element has the same function as for an Oracle Spatial and
Graph geometry theme. The <parameters> element defines the runtime parameters that
the provider accepts. For the shapefile provider, the runtime parameter filename
defines the path to the shapefile data.
You can override the runtime parameters section of a predefined custom geometry
theme by the specifying the parameters in a map_request. For example, you can
include the following in a <map_request> element:
<theme name="CUSTOM_THEME" >
<parameters>
<parameter name="filename" value="/lbs/demo/shapefile/counties.shp"/>
</parameters>
</theme>
2.3.10 Annotation Text Themes
Oracle Spatial and Graph supports annotation text as specified in the OpenGIS
Implementation Specification for Geographic information - Simple feature access - Part
1: Common architecture, which defines annotation text as "simply placed text that
can carry either geographically-related or ad-hoc data and process-related information
as displayable text. This text may be used for display in editors or in simpler maps. It is
usually lacking in full cartographic quality, but may act as an approximation to such
text as needed by any application."
Oracle Spatial and Graph provides the ST_ANNOTATION_TEXT object type for
storing annotation text, and the USER_ANNOTATION_TEXT_METADATA and
ALL_ANNOTATION_TEXT_METADATA views for storing metadata related to
annotation text. For more information about annotation text support, see Oracle Spatial
and Graph Developer's Guide.
Each annotation text object may have one or more elements, and each element is
defined by the following:
•
Value: Text associated with element. If the value is null, the text is derived from
the first non-null preceding element value. If all preceding elements have null
values, the text is a text expression value derived from the metadata.
•
Location: Spatial location associated with the annotation text object.
•
Leader line: Linear feature associated with the annotation text object.
•
Attributes: Graphic attributes used to display the text. If the value is null, graphic
attributes are derived from the attributes value in the metadata.
The text expression in the metadata views can be any of the following:
•
A column name.
•
A function applied to a column name. For example: substr(my_col,1,3)
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•
The concatenation of two or more column names. For example: column_1 ||
column_2 || column_3
•
A text value that is unrelated to a column name. In this case, it is treated as a
simple text string that is used for any text element that has a null value.
Annotation text themes in the map visualizer are associated with database tables that
have a column of type ST_ANNOTATION_TEXT. For each annotation text element,
the map visualizer will render:
•
The value (if not null) of the annotation text element as a string, using a text style
that is created at real time based on the element attributes.
•
The leader line (if not null) associated with the annotation text element. In this
case, users can select a map visualizer style to render the leader line.
Each annotation text element has an envelope represented by a geometry, and which
is used for spatial indexing. Therefore, you must do the following to use spatial
indexing with annotation text tables in the map visualizer:
1.
Insert a row into the USER_ANNOTATION_TEXT_METADATA view that specifies
the name of the annotation text table and the PRIVATEENVELOPE attribute of the
annotation text column (that is, the column of type ST_ANNOTATION_TEXT).
The following example inserts a row for a table named ANNOTEXT_TABLE with
an annotation text column named TEXTOBJ:
INSERT INTO USER_SDO_GEOM_METADATA
VALUES (
'ANNOTEXT_TABLE',
'TEXTOBJ.PRIVATEENVELOPE',
SDO_DIM_ARRAY(
SDO_DIM_ELEMENT('X', 0.0, 10.0, 0.0005),
SDO_DIM_ELEMENT('Y', 0.0,10.0, 0.0005)
),
null -- SRID
);
2.
Create a spatial index on the annotation text envelope of the annotation text table.
The following example creates a spatial index named ANNO_TEXT_IDX on the
annotation envelope of the table named ANNOTEXT_TABLE:
CREATE INDEX anno_text_idx ON annotext_table(textobj.privateenvelope)
INDEXTYPE IS mdsys.spatial_index;
For themes with valid SRID information, if the metadata base map scale is defined, the
element text sizes will be scaled as maps zoom in or out.
Example 2-35 defines the styling rules for a predefined annotation text theme in the
map visualizer. The structure is similar to other map visualizer themes. Currently, just
one styling rule is processed for each annotation theme. In this example, the theme
type is annotation, the feature style L.PH is used to render leader lines, and the query
condition (id = 1 or id = 2) is appended on the final query.
Example 2-36 shows the theme definition for a dynamic annotation text theme. The
parameters defined are:
•
datasource: the data source name
•
jdbc_srid: the spatial reference identifier
•
annotation_table: the annotation text table
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•
annotation_column: the annotation text column
•
leaderline_style: the leader line style to be used
Example 2-37 is similar to Example 2-36, but it adds the behavior that if the
annotation_column column contains a null value, then the value in the textexpr_column
is used for the annotation instead. In Example 2-37, assume that the
ANNOTATION_TABLE table contains a column named DEFAULT_ANNOTATION
(which is used in Example 2-38). This additional column is specified in the
textexpr_column attribute and in the SELECT statement.
Example 2-38 creates an annotation text table and prepares it to be used with the map
visualizer.
Example 2-35
Styling Rules for a Predefined Annotation Text Theme
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="annotation">
<rule>
<features style="L.PH"> (id = 1 or id = 2) </features>
</rule>
</styling_rules>
Example 2-36
Dynamic Annotation Text Theme Definition
<themes>
<theme name="theme1" >
<jdbc_annotation_query
datasource="tilsmenv"
jdbc_srid="0"
annotation_table="ANNOTEXT_TABLE"
annotation_column="textobj"
leaderline_style="L.PH"
>select textobj from annotext_table
</jdbc_annotation_query>
</theme>
</themes>
Example 2-37
Column
Dynamic Annotation Text Theme with Default Annotation
<themes>
<theme name="theme1" >
<jdbc_annotation_query
datasource="tilsmenv"
jdbc_srid="0"
annotation_table="ANNOTEXT_TABLE"
annotation_column="textobj"
textexpr_column="default_annotation"
leaderline_style="L.PH"
>select textobj, default_annotation from annotext_table
</jdbc_annotation_query>
</theme>
</themes>
Example 2-38
SET
SET
SET
SET
SET
ECHO ON
FEEDBACK
NUMWIDTH
LINESIZE
PAGESIZE
Script to Generate Annotation Text Data
1
10
100
10000
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SET SERVEROUTPUT ON SIZE 5000
SET LONG 20000
SET TIMING ON
call dbms_java.set_output(5000);
---------------------------------------------------------------------- Create an annotation text table (a table that has a
-- column of ST_ANNOTATION_TEXT object type), and insert some records.
--------------------------------------------------------------------create table annotext_table (
id number,
default_annotation varchar2(32),
textobj ST_ANNOTATION_TEXT);
insert into annotext_table values (1,'Text_1',
ST_ANNOTATION_TEXT(
ST_ANNOTATIONTEXTELEMENT_ARRAY(
ST_ANNOT_TEXTELEMENT_ARRAY(
ST_ANNOTATIONTEXTELEMENT('Sample Label 1',
SDO_GEOMETRY(2001, null, sdo_point_type(1,1,null),null,null),
SDO_GEOMETRY(2002,null,null,
SDO_ELEM_INFO_ARRAY(1,2,1),
SDO_ORDINATE_ARRAY(0,0, 1,1)), NULL)))));
insert into annotext_table values (2,'Text_2',
ST_ANNOTATION_TEXT(
ST_ANNOTATIONTEXTELEMENT_ARRAY(
ST_ANNOT_TEXTELEMENT_ARRAY(
ST_ANNOTATIONTEXTELEMENT('Sample Label 2',
SDO_GEOMETRY(2001,null,sdo_point_type(10,10,null),null,null),
SDO_GEOMETRY(2002,null,null,
SDO_ELEM_INFO_ARRAY(1,2,1),
SDO_ORDINATE_ARRAY(5,10, 10,10)), NULL)))));
insert into annotext_table values (3, 'Text_3',
ST_ANNOTATION_TEXT(
ST_ANNOTATIONTEXTELEMENT_ARRAY(
ST_ANNOT_TEXTELEMENT_ARRAY(
ST_ANNOTATIONTEXTELEMENT(null,
SDO_GEOMETRY(2002, null, null,
SDO_ELEM_INFO_ARRAY(1,2,1),
SDO_ORDINATE_ARRAY(2,5,4,5,6,5)),
SDO_GEOMETRY(2002,null,null,
SDO_ELEM_INFO_ARRAY(1,2,1),
SDO_ORDINATE_ARRAY(4,3, 4,5)),
'<?xml version="1.0" encoding="UTF-8" ?>
<textAttributes xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="../../annotation_text.xsd">
<textStyle fontFamily="Dialog" fontSize="14" fill="blue"/>
<textlayout/>
</textAttributes>'
)))));
---------------------------------------------------------------------- Register the annotation text table in the user metadata view.
--------------------------------------------------------------------insert into USER_ANNOTATION_TEXT_METADATA values(
'ANNOTEXT_TABLE', 'TEXTOBJ', null, null, null);
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---------------------------------------------------------------------- Update the metadata information.
--------------------------------------------------------------------update user_annotation_text_metadata set
text_expression='default_annotation',
text_attributes =
'<?xml version="1.0" encoding="UTF-8" ?>
<textAttributes xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="../../annotation_text.xsd">
<textStyle fontFamily="Serif" fontSize="14" fill="#ff0000"/>
<textlayout/>
</textAttributes>';
---------------------------------------------------------------------- Register the annotation text geometry envelope on the user
-- metadata view of geometries.
--------------------------------------------------------------------INSERT INTO USER_SDO_GEOM_METADATA
VALUES (
'ANNOTEXT_TABLE',
'TEXTOBJ.PRIVATEENVELOPE',
SDO_DIM_ARRAY(
SDO_DIM_ELEMENT('X', 0.0, 10.0, 0.0005),
SDO_DIM_ELEMENT('Y', 0.0,10.0, 0.0005)
),
null -- SRID
);
---------------------------------------------------------------------- Create a spatial index on the annotation text envelope.
--------------------------------------------------------------------create index anno_text_idx on annotext_table(textobj.privateenvelope)
indextype is mdsys.spatial_index;
---------------------------------------------------------------------- Insert a predefined theme into the map visualizer's theme view.
--------------------------------------------------------------------INSERT INTO user_sdo_themes VALUES (
'ANNOTEXT_THEME',
'Annotation text',
'ANNOTEXT_TABLE',
'TEXTOBJ',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="annotation">
<rule >
<features style="L.PH"> </features>
</rule>
</styling_rules>' );
commit;
2.3.11 LRS (Linear Referencing System) Themes
An LRS theme is a special kind of map visualizer theme useful for visualizing features
defined using the linear referencing system (LRS) of Oracle Spatial and Graph, which
is explained in Oracle Spatial and Graph Developer's Guide.
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Two tables are needed by an LRS theme: one (the LRS table) has an LRS geometry
column, and the other (the join table) has one or two measure columns. Point events
must have one measure column in the join table (for example, a road sign located at a
measure of m1, and an accident that occurred at a measure of m2); while linear
events must have two measure columns, one for a starting measure and one for an
end measure (for example, from measure m1 to measure m2 the road pavement
condition is poor, and from measure n1 to measure n2 the condition is fair). Each
event is stored in one row in the join table.
After an LRS theme is defined, you only need to specify the theme name in a map
request when you use the theme. The map visualizer automatically finds the theme's
definition and constructs a query that joins these two specified tables; it then
generates the geometry data by internally using an LRS function, either
SDO_LRS.LOCATE_PT for point events or SDO_LRS.CLIP_GEOM_SEGMENT for
linear events. The map visualizer then renders the generated point or linear segment,
together with their attribute data, according to the styling rules for the theme.
To create a predefined LRS theme, you must store the definition of the LRS theme in
the database by inserting a row into the USER_SDO_THEMES view. Example 2-39
stores the definition of an LRS theme named LRS_THEME.
In Example 2-39, the LRS table name (INTERSTATES_LRS, which has three
columns, GEOM, HIGHWAY, and ROUTEN) is inserted in the BASE_TABLE column
of the USER_SDO_THEMES view, the LRS geometry column (GEOM) is inserted in
the GEOMETRY_COLUMN column, and XML document with one <styling_rules>
element is inserted into the STYLING_RULES column.
In the <styling_rules> element for an LRS theme, theme_type must be lrs in order for
this theme to be recognized as an LRS theme.
If the optional key_column attribute is omitted, no key column is included when
constructing a query string to fetch data from a database. This is different from a
predefined geometry theme, in which the ROWID column is the default key column.
The child elements <rule>, <hidden_info>, <join_table>, and <join_columns> can be
included within the <styling_rules> element. The <join_table> and <join_columns>
child elements are specific to LRS themes.
The <rule> element for an LRS theme is similar to the definition in a predefined
themes, but its child element <features> must contain an asis attribute with its value
set to true (asis="true").There can be 0, 1, or more <rule> elements within a
<styling_rules> element.
The <hidden_info> element is optional for an LRS theme. It is defined for use in Oracle
Maps applications. It specifies a list of attributes from either the LRS table or the join
table, or both.
In <join_table> element, the name attribute (pavement_condition in this example)
specifies the join table name. In this example, the join table contains columns such as
id, seg_id, condition, from_measure, and to_measure. If two measure columns are
used to define linear events in the join table, then attributes start_measure and
end_measure (from_measure and to_measure in this example) must be specified, which
indicate column names of measurements in the join table. If the join table contains one
measure for point events, then a measure attribute is specified in this <join_table>
element.
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In the <join_columns> element, the lrs_table_column and join_table_column attributes
must be specified, where lrs_table_column defines the column from the LRS table, and
join_table_column specifies the column from the join table to join these two tables.
Example 2-40 shows a map request that uses the predefined LRS theme from
Example 2-39.
See Also:
XML Format for Styles, Themes, Base Maps, and Map Tile Layers for
reference information about elements and attributes specific to LRS themes
(such as the <join_table> and <join_columns> elements).
Example 2-39
Creating an LRS Theme
INSERT INTO user_sdo_themes (name, description, base_table, geometry_column,
styling_rules)
VALUES (
'LRS_THEME',
'LRS theme example with 3 rules, 2 measure columns',
'INTERSTATES_LRS',
'GEOM',
'<?xml version="1.0" standalone="yes"?>
<styling_rules key_column="id" theme_type="lrs">
<rule>
<features asis="true">
condition=''good''
</features>
<label column="condition" style="T.STREET NAME"/>
<rendering>
<style name="L.PTH"/>
</rendering>
</rule>
<rule>
<features asis="true">
condition=''fair''
</features>
<label column="condition" style="T.STREET NAME"/>
<rendering>
<style name="L.SH"/>
</rendering>
</rule>
<rule>
<features asis="true">
condition=''poor''
</features>
<label column="condition" style="T.STREET NAME"/>
<rendering>
<style name="L.MAJOR STREET"/>
</rendering>
</rule>
<hidden_info>
<field column="highway"
name="highway name"/>
<field column="routen"
name="highway number"/>
<field column="condition"
name="pavement condition"/>
</hidden_info>
<join_table
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name="pavement_condition"
start_measure="from_measure"
end_measure="to_measure"
/>
<join_columns
lrs_table_column="highway"
join_table_column="seg_id"
/>
</styling_rules>'
);
Example 2-40
Map Request with Predefined LRS Theme
<?xml version="1.0" standalone="yes"?>
<map_request
title="LRS Theme test"
datasource="mvdemo"
width="640"
height="480"
bgcolor="#a6caf0"
antialiase="true"
format="PNG_STREAM">
<center size="45">
<geoFeature>
<geometricProperty typeName="center">
<Point>
<coordinates>-95, 35</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="LRS_THEME"/>
</themes>
</map_request>
2.3.12 Thematic Mapping
Thematic mapping refers to the drawing of spatial features based on their attribute
values. The map visualizer uses thematic mapping to create maps in which colors or
symbols are applied to features to indicate their attributes. For example, a Counties
theme can be drawn using colors with different hues that map directly to the population
density of each county, or an Earthquakes theme can be plotted with filled circles
whose sizes map to the scale or damage of each earthquake.
To achieve thematic mapping, you must first create an advanced style that is suitable
for the type of thematic map, and then create a theme for the features specifying the
advanced style as the rendering style. In the styling rules for the theme, you must also
specify attribute columns in the table or view whose values will be used to determine
exactly how a feature will be rendered thematically by the advanced style.
For example, assume that you wanted to display a map in which the color used for
each region reflects the level of sales for a particular product. To do this, create an
advanced style that defines a series of individual range-based buckets (see Individual
Range-Based Buckets), where each bucket contains a predefined range of sales
values for a product, and each bucket has an associated rendering style. (Each region
will be rendered using the style associated with the range in which that region's sales
value falls.) Also specify the name of the column or columns that provide the attribute
values to be checked against the ranges. In other words, the advanced style defines
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how to map regions based on their sales values, and the theme's styling rules tie
together the advanced style and the attribute column containing the actual sales
values.
Figure 2-13 shows the relationship between an advanced style and a theme, and how
the style and the theme relate to the base table. In this figure, the advanced style
named V.SALES defines the series of buckets. The predefined theme named
SALES_BY_REGION specified the V.SALES style in its styling rules. The theme also identifies
the SALES column in the REGIONS table as the column whose value is to be
compared with the bucket ranges in the style. (Each bucket could be associated with a
labeling style in addition to or instead of a rendering style, as explained in Specifying a
Label Style for a Bucket.)
Figure 2-13
Thematic Mapping: Advanced Style and Theme Relationship
In addition to the individual range-based buckets shown in Figure 2-13, the map
visualizer supports other bucket styles, as explained in Bucket Styles. You can also
use more than one attribute column for thematic mapping, such as when drawing pie
charts.
The rest of this section presents additional examples of thematic mapping.
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Example 2-41 is the XML definition for an Earthquakes theme.
Note:
The label attribute value (for example, label="less than 4") is not displayed
on the map, but is used only in a label that is compiled for an advanced style.
The seq attribute value (for example, seq="0") is ignored by the map visualizer,
which determines sequence only by the order in which elements appear in a
definition.
Example 2-42 used the <VariableMarkerStyle> tag. The following examples use the
<ColorSchemeStyle> tag in creating thematic maps of census blocks in California.
Example 2-43 illustrates the use of a graduated color scale for a thematic mapping of
population density. Example 2-44 is a thematic mapping of average household income
using a graduated color scale. Example 2-45 is also a thematic mapping of average
household income, but it uses a specific color style for each income range rather a
graduated scale.
•
m.esso gasstation, m.texaco gasstation, and the other style names have a space
between the words in their names.
•
The names are not case-sensitive. Therefore, be sure not to use case as a way of
differentiating names. For example, m.esso gasstation and M.ESSO GASSTATION are
considered the same name.
•
A default collection bucket can be specified by using #DEFAULT# as its value. This
bucket is used for any column values (gas station names) that are not specified in
the other buckets.
A theme (theme_gasstation) is then defined that specifies the column (MERK) in the
table that contains company names. The styling rules of the theme are shown in
Example 2-47.
Table 2-2
Table Used with Gasoline Stations Theme
Column
Data Type
FID
NOT NULL NUMBER
ID
NUMBER
NAAM
VARCHAR2(31)
STRAAT_
VARCHAR2(30)
NR
NUMBER
TV
VARCHAR2(1)
AAND
VARCHAR2(2)
PCODE
VARCHAR2(6)
PLAATS
VARCHAR2(10)
GEOM
SDO_GEOMETRY
MERK
VARCHAR2(40)
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In this table, the GEOM column contains spatial geometries, and the MERK column
contains company names (Shell, Esso, and so on).
The styling rules for the theme_gasstation theme specify that the marker (style
v.gasstations) at a location specified by the content of the GEOM column is
determined by the value of the MERK column for that row. The style v.gasstations
(see Example 2-46) specifies that if the column value is Shell, use the style m.shell
gasstation; if the column value is Esso, use the style m.esso gasstation; and so on,
including if the column value is any one of Avia, Benzinex, Q8, Total, and Witte Pomp,
use the style m.generic gasstation; and if the column value is none of the preceding,
use the style m.default gasstation.
Example 2-41
XML Definition of Styling Rules for an Earthquakes Theme
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="nature">
<rule column="RICHTER_SCALE">
<features style="v.earthquakes">
</features>
</rule>
</styling_rules>
The theme in Example 2-41 has only one rule. The <rule> element includes an
attribute named column that does not appear in the Airport theme in Example 2-6. The
column attribute specifies one or more columns (comma-delimited) that provide the
attribute values needed for thematic mapping. The style specified for the <features>
element is named v.earthquakes, and it is an advanced style.
Another part of the definition of the Earthquakes theme specifies the table that contains
the data to be rendered. This table must contain a column named RICHTER_SCALE
in addition to a column (of type SDO_GEOMETRY) for the spatial data. (The table and
the column of type SDO_GEOMETRY must be identified in the BASE_TABLE and
GEOMETRY_COLUMN columns, respectively, of the USER_SDO_THEMES view,
which is described in xxx_SDO_THEMES Views.) The RICHTER_SCALE column
must be of type NUMBER. To understand why, look at the advanced style definition in
Example 2-42.
Example 2-42
Advanced Style Definition for an Earthquakes Theme
<?xml version="1.0" ?>
<AdvancedStyle>
<VariableMarkerStyle basemarker="m.circle" startsize="7" increment="4">
<Buckets>
<RangedBucket seq="0" label="less than 4" high="4"/>
<RangedBucket seq="1" label="4 - 5" low="4" high="5"/>
<RangedBucket seq="2" label="5 - 6" low="5" high="6"/>
<RangedBucket seq="3" label="6 - 7" low="6" high="7"/>
<RangedBucket seq="4" label="7 and up" low="7"/>
</Buckets>
</VariableMarkerStyle>
</AdvancedStyle>
This style specifies that the marker named m.circle is used to indicate the location of
an earthquake. The size of the marker to be rendered for an earthquake depends on
the numeric value of the RICHTER_SCALE column for that row. In this example there
are five buckets, each covering a predetermined range of values. For example, if an
earthquake is of magnitude 5.7 on the Richter scale, the marker size will be 15 pixels
(7 + 4 + 4), because the value 5.7 falls in the third bucket (5 - 6) and the starting
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marker size is 7 pixels (startsize="7") with an increment of 4 for each range
(increment="4").
Example 2-43
Mapping Population Density Using a Graduated Color Scheme
# ca pop density usbg_hhinfo
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="political">
<rule column="densitycy">
<features style="v.CA Pop density">
</features>
</rule>
</styling_rules>
The table named USBG_HHINFO includes a column named DENSITYCY (used in
Example 2-43). The definition of the style (v.CA Pop density) that corresponds to this
population density theme is as follows:
<?xml version="1.0" ?>
<AdvancedStyle>
<ColorSchemeStyle basecolor="#ffff00" strokecolor="#00aaaa">
<Buckets low="0.0" high="20000.0" nbuckets="10"/>
</ColorSchemeStyle>
</AdvancedStyle>
The base color (basecolor) and the stroke color (strokecolor) are 24-bit RGB (redgreen-blue) values specified using a hexadecimal notation. The base color value is
used for the first bucket. The color value for each subsequent bucket is obtained by
first converting the base color from the RGB to the HSB (hue-saturation-brightness)
model and then reducing the brightness by a fixed increment for each bucket. Thus,
the first bucket is the brightest and the last is the darkest.
As in Example 2-43, Example 2-44 illustrates the use of a base color and a graduated
color scheme, this time to show household income.
Example 2-44
Scheme
Mapping Average Household Income Using a Graduated Color
<?xml version="1.0" standalone="yes"?>
<!-- # ca hh income theme table = usbg_hhinfo -->
<styling_rules>
<rule column="avghhicy">
<features style="v.ca income">
</features>
</rule>
</styling_rules>
The table named USBG_HHINFO includes a column named AVGHHICY (used in
Example 2-44 and Example 2-45). The definition of the style (v.ca income) that
corresponds to this average household income theme is as follows:
<?xml version="1.0" ?>
<AdvancedStyle>
<ColorSchemeStyle basecolor="#ffff00" strokecolor="#00aaaa">
<!-- # income range with a color gradient -->
<Buckets>
<RangedBucket seq="0" label="less than 10k" high="10000"/>
<RangedBucket seq="1" label="10-15k" low="10000" high="15000"/>
<RangedBucket seq="2" label="15-20k" low="15000" high="20000"/>
<RangedBucket seq="3" label="20-25k" low="20000" high="25000"/>
<RangedBucket seq="4" label="25-35k" low="25000" high="35000"/>
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<RangedBucket
<RangedBucket
<RangedBucket
<RangedBucket
<RangedBucket
<RangedBucket
<RangedBucket
<RangedBucket
</Buckets>
</ColorSchemeStyle>
</AdvancedStyle>
seq="5" label="35-50k" low="35000" high="50000"/>
seq="6" label="50-75k" low="50000" high="75000"/>
seq="7" label="75-100k" low="75000" high="100000"/>
seq="8" label="100-125k" low="100000" high="125000"/>
seq="9" label="125-150k" low="125000" high="150000"/>
seq="10" label="150-250k" low="150000" high="250000"/>
seq="11" label="250-500k" low="250000" high="500000"/>
seq="12" label="500k and up" low="500000"/>
For individual range-based buckets, the lower-bound value is inclusive, while the
upper-bound value is exclusive (except for the range that has values greater than any
value in the other ranges; its upper-bound value is inclusive). No range is allowed to
have a range of values that overlaps values in other ranges.
Example 2-45 uses specific color styles for each average household income range.
Example 2-45 Mapping Average Household Income Using a Color for Each
Income Range
<?xml version="1.0" standalone="yes"?>
<!-- # ca hh income theme table = usbg_hhinfo -->
<styling_rules>
<rule column="avghhicy">
<features style="v.ca income 2">
</features>
</rule>
</styling_rules>
The definition of the v.ca income 2 style is as follows:
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets>
<!-- # income ranges with specific colors -->
<RangedBucket seq="0" label="less than 10k" high="10000" style="c.rb13_1"/>
<RangedBucket seq="1" label="10-15k" low="10000" high="15000" style="c.rb13_2"/>
<RangedBucket seq="2" label="15-20k" low="15000" high="20000" style="c.rb13_3"/>
<RangedBucket seq="3" label="20-25k" low="20000" high="25000" style="c.rb13_4"/>
<RangedBucket seq="4" label="25-35k" low="25000" high="35000" style="c.rb13_5"/>
<RangedBucket seq="5" label="35-50k" low="35000" high="50000" style="c.rb13_6"/>
<RangedBucket seq="6" label="50-75k" low="50000" high="75000" style="c.rb13_7"/>
<RangedBucket seq="7" label="75-100k" low="75000" high="100000" style="c.rb13_8"/>
<RangedBucket seq="8" label="100-125k" low="100000" high="125000" style="c.rb13_9"/>
<RangedBucket seq="9" label="125-150k" low="125000" high="150000" style="c.rb13_10"/>
<RangedBucket seq="10" label="150-250k" low="150000" high="250000" style="c.rb13_11"/>
<RangedBucket seq="11" label="250-350k" low="250000" high="350000" style="c.rb13_12"/>
<RangedBucket seq="12" label="350k and up" low="350000" style="c.rb13_13"/>
</Buckets>
</BucketStyle>
</AdvancedStyle>
Each <RangedBucket> definition has a specified style.
The following examples create an advanced style to identify gasoline stations operated
by different oil companies, and a theme that uses the style. A <CollectionBucket> tag is
used to associate a column value (Shell; Esso; Texaco; BP; any of Avia, Benzinex, Q8,
Total, Witte Pomp; and all others for a default category) with a style appropriate for that
company's stations, as shown in Example 2-46.
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Example 2-46
Advanced Style Definition for Gasoline Stations Theme
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets>
<CollectionBucket seq="0" label="Shell" style="m.shell gasstation">
Shell
</CollectionBucket>
<CollectionBucket seq="1" label="Esso" style="m.esso gasstation">
Esso
</CollectionBucket>
<CollectionBucket seq="2" label="Texaco" style="m.texaco gasstation">
Texaco
</CollectionBucket>
<CollectionBucket seq="3" label="BP" style="m.bp gasstation">
BP
</CollectionBucket>
<CollectionBucket seq="4" label="Other" style="m.generic gasstation">
Avia,Benzinex,Q8,Total,Witte Pomp
</CollectionBucket>
<CollectionBucket seq="5" label="DEFAULT" style="m.default gasstation">
#DEFAULT#
</CollectionBucket>
</Buckets>
</BucketStyle>
</AdvancedStyle>
Notes on Example 2-46:
Example 2-47
Styling Rules of Theme Definition for Gasoline Stations
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule column="merk">
<features style="v.gasstations">
</features>
<label column="merk" style="t.SansSerif red 10">
1
</label>
</rule>
</styling_rules>
This theme depends on a table named NED_GASSTATIONS, which has the columns
shown in Table 2-2 (with column names reflecting the fact that the developer's
language is Dutch).
•
Thematic Mapping Using External Attribute Data
2.3.12.1 Thematic Mapping Using External Attribute Data
Previous discussion of thematic mapping has assumed that both the attribute data
(such as population of sales totals) and the geospatial data (geometry objects
representing boundaries, locations, and so on) are in the same database. However,
the attribute data can come from a source outside the current database; for example,
the attribute data might reflect aggregated results of a business intelligence (BI) query
performed on a different database, or the attribute data might come from a commadelimited list of sales values exported from a spreadsheet. Such attribute data, from
outside the database that contains the geospatial data, is called external attribute
data.
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To use external attribute data with the map visualizer, you must use the nonspatial
data provider plug-in mechanism, in which a custom data provider is associated with
a map visualizer theme (predefined or dynamic) in the same map request. When the
map visualizer processes the theme, it calls the nonspatial data provider to join
nonspatial attribute data with the spatial data that has been fetched for the theme.
To use a nonspatial data provider, follow these steps:
1.
Implement your Java nonspatial data provider by implementing the map visualizer
defined interface oracle.mapviewer.share.ext.NSDataProvider.
2.
Register the nonspatial data provider implementation with the map visualizer (in its
configuration file). There you can also specify a set of global parameters that your
implementation may depend on. Each custom data provider implementation class
must have a unique ID that you assign.
3.
Place a library containing the nonspatial data provider implementation classes in
the library path of the map visualizer, such as its web/WEB-INF/lib directory.
4.
Include the nonspatial data provider implementation in a map request by invoking
the following method on the map visualizer Java client API class MapViewer:
addNSDataProvider(java.lang.String providerId,
java.lang.String forTheme,
java.lang.String spatialKeyColumn,
java.lang.String customRenderingStyle,
java.util.Properties params,
long timeout)
For information about the addNSDataProvider parameters, see the Javadoc
reference information for the map visualizer, available at a URL in the form http://
host:port/mapviewer/mapclient, where host and port indicate where Oracle Fusion
Middleware listens for incoming requests. For example: http://www.mycorp.com:
8888/mapviewer/mapclient
Example 2-48 shows a simple nonspatial data provider implementation. This
implementation is also supplied with the map visualizer as a default nonspatial data
provider.
Example 2-48
Nonspatial (External) Data Provider Implementation
import
import
import
import
java.io.BufferedReader;
java.io.FileReader;
java.util.Properties;
java.util.Vector;
import
import
import
import
oracle.mapviewer.share.ext.NSDataSet;
oracle.mapviewer.share.ext.NSDataProvider;
oracle.mapviewer.share.ext.NSRow;
oracle.lbs.util.Logger;
import oracle.mapviewer.share.Field;
/**
* A simple implementation of the NSDataProvider interface. When invoked, it
supplies tabular attribute data to the map visualizer out
* of a file or URL. The data in the file must be orgazined as following: <br>
* <UL>
* <LI> The first line contain a single character which is the delimiter
*
between columns in the subsequent lines.
* <LI> Each line after the first in the file represent one data row
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* <LI> Each field in the row must be separated by the delimiter char only
* <LI> The first field in each line must be a string (key) that serves as the
*
key; the rest of the fields must be numeric values
* </UL>
*
* When incorporating this data provider in a map request, one of the following
* two parameters must be specified:
* <UL>
* <LI> file if the custom data is stored in a local file; this parameter
*
specifies the full path to that file
* <LI> url if the custom data can be accessed from a web; this parameter
*
specifeis the full URL to the data file.
* </UL>
*
*
*/
public class NSDataProviderDefault implements NSDataProvider
{
private static Logger log = Logger.getLogger("oracle.sdovis.nsdpDefault");
public boolean init(Properties params)
{
return true;
}
public NSDataSet buildDataSet(Properties params)
{
String file = params.getProperty("file");
if(file!=null)
return readFromFile(file);
String url = params.getProperty("url");
if(url!=null)
return readFromUrl(url);
log.error("Must supply either file or url for default NS data provider.");
return null;
}
public void destroy()
{
}
protected NSDataSet readFromFile(String file)
{
BufferedReader in = null;
try{
in = new BufferedReader(new FileReader(file));
String line = in.readLine();
String delimiter = line.substring(0,1);
Vector rows = new Vector();
while ( (line=in.readLine()) != null)
{
NSRow row = buildRow(line, delimiter);
if(row!=null)
rows.add(row);
}
NSDataSet res = new NSDataSet(rows);
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return res;
}catch(Exception ex)
{
log.error(ex);
return null;
} finally
{
try{
if(in!=null)
in.close();
}catch(Exception e){}
}
}
protected NSDataSet readFromUrl(String url)
{
log.error("url not supported yet.");
return null;
}
protected NSRow buildRow(String line, String delimiter)
{
if(line==null || line.length()<1)
return null;
String[] fields = line.split(delimiter);
if(fields==null || fields.length==0)
return null;
Field[] row = new Field[fields.length];
Field a = new Field(fields[0]);
a.setKey(true);
row[0] = a;
for (int i = 1; i < fields.length; i++)
{
try{
double d = Double.parseDouble(fields[i]);
a = new Field(d);
row[i] = a;
}catch(Exception e)
{
log.warn("invalid row field (key="+fields[0]+")");
return null;
}
}
return new NSRow(row);
}
}
2.3.13 Attributes Affecting Theme Appearance
Some attributes of the <theme> element affect only the appearance of the map display,
rather than determining the data to be associated with the theme. These appearancerelated attributes control whether and how the theme is processed and rendered when
a map is generated. Examples include the following attributes:
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•
min_scale and max_scale determine whether or not a theme is displayed at various
map scales (levels of resolution). For example, if you are displaying a map of
streets, there are certain map scales at which the streets would become too dense
for a usable display, such as when viewing an entire state or province. In this
case, you should create a theme for streets, and specify minimum and maximum
scale values to ensure that individual streets affected by the theme are displayed
when the scale is appropriate and otherwise are not displayed.
•
labels_always_on determines whether or not labels for the theme will be displayed
if they would overlap another label. By choosing appropriate labels_always_on
values and choosing an appropriate order of themes to be processed within a map
request, you can control how cluttered the labels might become and which labels
have priority in getting displayed.
•
fast_unpickle determines the unpickling (unstreaming) method to be used, which
can involve a trade-off between performance and precision in the display.
•
fixed_svglabel, visible_in_svg, selectable_in_svg, onclick, onmousemove,
onmouseover, and onmouseout affect the appearance of SVG maps.
To specify any appearance-related attributes, use the <theme> element (described in
[31.2.20]) with the XML API.
2.4 Maps
A map can consist of a combination of elements and attributes.
These elements and attributres can include the following:
•
Background image
•
Title
•
Legend
•
Query window
•
Footnote (such as for a copyright notice)
•
Base map
•
Predefined themes (in addition to any in the base map)
•
JDBC themes (with dynamic queries)
•
Dynamically defined (temporary) styles
These elements and attributes, when specified in a map request, define the content
and appearance of the generated map. Map Visualization Servers contains detailed
information about the available elements and attributes for a map request.
A map can have a base map and a stack of themes rendered on top of each other in a
window. A map has an associated coordinate system that all themes in the map must
share. For example, if the map coordinate system is 8307 (for Longitude / Latitude
(WGS 84), the most common system used for GPS devices), all themes in the map
must have geometries defined using that coordinate system.
You can add themes to a map by specifying a base map name or by using the
programming interface to add themes. The order in which the themes are added
determines the order in which they are rendered, with the last specified theme on top,
so be sure you know which themes you want in the background and foreground.
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All base map names and definitions for a database user are stored in that user's
USER_SDO_MAPS view, which is described in Map Visualizer Metadata Views and
xxx_SDO_MAPS Views. The DEFINITION column in the USER_SDO_MAPS view
contains an XML definition of a base map.
Example 2-49 shows a base map definition.
Example 2-49
XML Definition of a Base Map
<?xml version="1.0" ?>
<map_definition>
<theme name="theme_us_states"
<theme name="theme_us_parks"
<theme name="theme_us_highways"
<theme name="theme_us_streets"
</map_definition>
min_scale="10" max_scale="0"/>
min_scale="5" max_scale="0"/>
min_scale="5" max_scale="0"/>
min_scale="0.05" max_scale="0"/>
Each theme in a base map can be associated with a visible scale range within which it
is displayed. In Example 2-49, the theme named theme_us_streets is not displayed
unless the map request is for a map scale of 0.05 or less and greater than 0 (in this
case, a scale showing a great deal of detail). If the min_scale and max_scale attributes
are not specified, the theme is displayed whenever the base map is displayed. (For
more information about map scale, see Map Size and Scale.)
The display order of themes in a base map is the same as their order in the base map
definition. In Example 2-49, the theme_us_states theme is rendered first, then
theme_us_parks, then theme_us_highways, and finally (if the map scale is within all
specified ranges) theme_us_streets.
•
Map Size and Scale
•
Map Legend
2.4.1 Map Size and Scale
Map size is the height of the map in units of the map data space. For example, if the
map data is in WGS 84 geographic coordinates, the map center is (-120.5, 36.5), and
the size is 2, then the height of the map is 2 decimal degrees, the lower Y (latitude)
value is 35.5 degrees, and the upper Y value is 37.5 decimal degrees.
Map scale is expressed as units in the user's data space that are represented by 1
inch on the screen or device. Map scale for the map visualizer is actually the
denominator value in a popular method of representing map scale as 1/n, where:
•
1, the numerator, is 1 unit (1 inch for the map visualizer) on the displayed map.
•
n, the denominator, is the number of units of measurement (for example, decimal
degrees, meters, or miles) represented by 1 unit (1 inch for the map visualizer) on
the displayed map.
For example:
•
If 1 inch on a computer display represents 0.5 decimal degree of user data, the
fraction is 1/0.5. The decimal value of the fraction is 2.0, but the scale value for the
map visualizer is 0.5.
•
If 1 inch on a computer display represents 2 miles of user data, the fraction is 1/2.
The decimal value of the fraction is 0.5, but the scale value for the map visualizer
is 2.
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•
If 1 inch on a computer display represents 10 miles of user data, the fraction is
1/10. The decimal value of the fraction is 0.1, but the scale value for the map
visualizer is 10.
The min_scale and max_scale attributes in a <theme> element describe the visible scale
range of a theme. These attributes control whether or not a theme is displayed,
depending on the current map scale. The default scale value for min_scale is positive
infinity, and the default value for max_scale is negative infinity (or in other words, by
default display the theme for all map scales, if possible given the display
characteristics).
•
min_scale is the value to which the display must be zoomed in for the theme to be
displayed. For example, if parks have a min_scale value of 5 and if the current map
scale value is 5 or less but greater than the max_scale value, parks will be included
in the display; however, if the display is zoomed out so that the map scale value is
greater than 5, parks will not be included in the display.
•
max_scale is the value beyond which the display must be zoomed in for the theme
not to be displayed. For example, if counties have a max_scale value of 3 and if the
current map scale value is 3 or less, counties will not be included in the display;
however, if the display is zoomed out so that the map scale value is greater than
3, counties will be included in the display.
A high min_scale value is associated with less map detail and a smaller scale in
cartographic terms, while a high max_scale value is associated with greater map detail
and a larger scale in cartographic terms. (Note that the map visualizer meaning of map
scale is different from the popular meaning of cartographic map scale.) The min_scale
value for a theme should be larger than the max_scale value. Example 2-49 in Maps
includes min_scale and max_scale values.
You also assign scale values for theme labels, to enable the showing or hiding of
labels with values different from the base theme scales, by using the theme label scale
parameters label_min_scale and label_max_scale. These parameters are similar to the
min_scale and max_scale parameters, but the labels are shown if the map scale is in the
visible range defined by label_min_scale and label_max_scale. (The label scale values
are ignored if the theme is not in the visible scale range defined by min_scale and
max_scale.) The following is a theme definition with label scale values; the labels will be
shown when the map scale is between 5 and 2, but the theme features will be shown
when the map scale is between 10 and 0:
<theme name="theme_us_states" min_scale="10" max_scale="0"
label_min_scale="5" label_max_scale="2"/>
To determine the current map scale for a map returned by the map visualizer, first find
the map size, namely the height (vertical span) of the map in terms of the coordinate
system associated with the map data. For example, assume that a map with a height
of 10 (miles, meters, decimal degrees, or whatever unit of measurement is associated
with the data) is requested, and that the map is drawn on a device with a size of 500
by 350 pixels, where 350 is the height. The map visualizer assumes a typical screen
resolution of 96 dpi. Because 96 pixels equals 1 inch, the height of the returned map is
3.646 inches (350/96 = 3.646). In this example, the size of the map is 10, and
therefore the map scale is approximately 2.743 (10/3.646 = 2.743).
Alternatively, you can request a map using a map scale value without specifying a unit,
such as 50000 for a scale of 1:50000, by specifying the scale_mode theme attribute
value as ratio. (If the scale_mode theme attribute value is screen_inch, the scale refers
to a unit.) To use a scale defined without a unit, request the map specifying the center
and ratio scale.
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To find the equivalent map visualizer screen inch scale for a ratio scale, follow these
steps:
1.
Find the numerical fraction of a meter associated with one screen pixel. For
example, if the screen resolution is 96 dpi (dots per inch), the number of meters on
the screen for each screen pixel is 0.000265 (that is, 0.0254/96).
2.
Find the map scale for one screen pixel (the mapdotScale value), as follows:
3.
•
For projected data (meters), multiply the result of step 1 by the ratio scale. For
example, if the ratio scale is 50000 (50 thousand) and the screen resolution is
96 dpi, the result is 13.25 meters for each pixel (50000 * 0.000265).
•
For geodetic data (degrees), multiply the result of step 1 by the number of
meters (on the surface of the Earth) for each degree. (This number will depend
on the coordinate system associated with the data.) For example, if one
degree = 111195 meters and if the screen resolution is 96 dpi, the result is
29.466675 meters for each pixel (111195 * 0.000265).
•
For data using any other unit, use the approach for projected data using
meters.
Because the map visualizer scale is per screen inch instead of per screen pixel,
multiply the result of step 2 by the dpi value. For example, if the result of step 2 is
13.25 meters at 96 dpi, the number of meters for each screen inch is 1272 (13.25 *
96).
2.4.2 Map Legend
A map legend is an inset illustration drawn on top of the map and describing what
various colors, symbols, lines, patterns, and so on represent. You have flexibility in
specifying the content and appearance of the legend. You can:
•
Customize the background, border style, and font
•
Have one or more columns in the legend
•
Add space to separate legend entries
•
Indent legend entries
•
Use any map visualizer style, including advanced styles
Example 2-50 is an excerpt from a request that includes a legend.
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Figure 2-14
Map with Legend
Notes on Example 2-50 and Figure 2-14:
•
This example shows a legend with a single column, although you can create
multiple columns in a legend.
•
Each entry in the column definition can identify label text and whether the text is
the legend title (is_title="true"), a style name and associated text, or a separator
(is_separator="true") for vertical blank space to be added (after the cities entry in
this example).
As an alternative to specifying the legend content in one or more <column> elements,
you can request an automatic legend based on the map request. With an automatic
legend, you specify the legend header, and the map visualizer generates the legend
based on the themes that have any interaction with the map area. Themes from the
map request and from the base map are considered. (Some legend items might not be
visible, though, such as if a theme interacts with the query window but no features of
the theme are visible on the map.)
Example 2-51 is a map request that requests an automatic legend (because the
<legend> element does not include any <column> elements).
Example 2-52 requests an automatic legend in which the <legend> elements specifies
the themes to be used to generate the legend items. In this example, even if the map
result shows more themes, the legend items are based on the THEME_COUNTIES_3397829
and THEME_US_AIRPORT themes specified in the <legend> element.
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You cannot combine an automatic legend with the use of <column> elements. If the
<legend> element contains any <column> elements, a column/entry legend is created.
The map visualizer uses the following considerations when it builds automatic legend
items:
•
Each legend column has a maximum of five entries (an advanced style is
considered one entry).
•
The legend text for simple rendering styles comes from the theme description if
defined, otherwise from the theme name.
•
If a rendering style is used in more than one theme, the style is repeated in the
legend but with text related to the theme to which it applies.
•
Labeling styles are not repeated in the legend. The style text for labeling styles
comes from the style description.
•
Advanced styles are not repeated in the legend.
If you also specify a map title, note, or logo (or any combination), be sure that the
legend and the other features have different positions. (Map titles, notes, and logos
are explained in Specifying Global Map Configuration Options.) The default position for
a legend is SOUTH_WEST.
Example 2-50
Legend Included in a Map Request
<?xml version="1.0" standalone="yes"?>
<map_request
basemap="density_map"
datasource = "mvdemo"
width="640"
height="480"
bgcolor="#a6cae0"
antialiase="false"
format="PNG_STREAM">
<center size="4.2">
<geoFeature render_style="m.image134_bw">
<geometricProperty typeName="center">
<Point srsName="SDO:8307">
<coordinates>-121.2615, 37.5266</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<legend bgstyle="fill:#ffffff;fill-opacity:100;stroke:#a3a3a3" profile="MEDIUM"
position="SOUTH_WEST">
<column>
<entry text="Legend" is_title="true" />
<entry style="M.IMAGE134_BW" text="Center" />
<entry style="M.ALL_CITY_L2" text="Cities" />
<entry is_separator="true" />
<entry style="L.S04_ROAD_INTERSTATE" text="Interstates" />
<entry text="County population:" />
<entry style="V.COUNTY_POP_DENSITY_8" tab="1" />
</column>
</legend>
<!-<themes>
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</themes>
-->
</map_request>
Figure 2-14 shows a map with the legend specified in Example 2-50.
Example 2-51
Map Request with Automatic Legend
<?xml version="1.0" standalone="yes"?>
<map_request
title="Automatic legend"
datasource = "mvdemo"
width="640"
height="480"
bgcolor="#a6cae0"
antialiase="false"
format="PNG_STREAM">
<center size="4.5">
<geoFeature >
<geometricProperty typeName="center">
<Point>
<coordinates>-122.2615, 37.5266</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="THEME_COUNTIES_3397829" />
<theme name="THEME_US_ROAD1" />
<theme name="THEME_US_AIRPORT" />
</themes>
<legend bgstyle="fill:#ffffff;fill-opacity:128;stroke:#ff0000;stroke-opacity:128"
profile="medium" font="Courier">
</legend>
</map_request>
Example 2-52
Automatic Legend with Themes Specified
<map_request
title="Legend with themes defined"
datasource = "mvdemo"
width="640"
height="480"
bgcolor="#a6cae0"
antialiase="false"
format="PNG_STREAM">
<center size="4.5">
<geoFeature >
<geometricProperty typeName="center">
<Point>
<coordinates>-122.2615, 37.5266</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="THEME_COUNTIES_3397829" />
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<theme name="THEME_US_ROAD1" />
<theme name="THEME_US_AIRPORT" />
</themes>
<legend bgstyle="fill:#ffffff;fill-opacity:128;stroke:#ff0000;stroke-opacity:128"
profile="medium" font="Courier">
<themes>
<theme name="THEME_COUNTIES_3397829" />
<theme name="THEME_US_AIRPORT" />
</themes>
</legend>
</map_request>
2.5 Data Sources
A data source corresponds to a database schema or user.
Before you can draw any spatial data in a database schema, you must first define
(create) a data source for the schema, either permanently or dynamically:
•
You can define a data source permanently by specifying its connection information
and user login credentials in the map visualizer configuration file
(mapViewerConfig.xml).
•
You can define or modify a data source dynamically using the map visualizer
administration (Admin) page.
Each map request must specify a master data source. You can, however, specify a
different data source for individual themes added to the map request. This makes it
easy to aggregate data stored across different database schemas. If a theme has no
specified data source, it is associated with the master data source. A base map (and
thus the themes included in it) is always associated with the master data source.
When a theme is processed, all of its underlying data, as well as the styles referenced
in its definition, must be accessible from the data source or sources associated with
the theme.
Each data source has associated renderers (sometimes called mappers or map
makers), the number of which is determined by the number_of_mappers attribute in the
<map_data_source> element. This attribute (described in Defining Permanent Map Data
Sources) affects the number of database connections created for each data source
when map requests are processed. The number of renderers specified in a data
source also is the maximum number of concurrent requests that can be processed for
that data source. Each additional renderer requires only a small amount of memory, so
the main potential disadvantage of specifying a large number of renderers (such as
100) is that the underlying CPU resource might be strained if too many map requests
are allowed to come through, thus affecting the performance of the entire map
visualizer server.
Each data source has its own internal metadata cache. The metadata cache holds the
definitions of all accessed styles, as well as of all predefined themes that originate
from the data source. This eliminates the need to query the database repeatedly for
the definition of a style or predefined theme whenever it is needed.
•
Catalog Data Sources
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2.5.1 Catalog Data Sources
A catalog data source gets all of its data from local files. The local directory where the
data files are stored is relative to where the mapViewerConfig.xml file is stored. From
another perspective, a catalog data source does not need the Oracle database,
because all necessary data (the spatial geometry data and its attributes, as well as the
metadata for how to rend the spatial data, such as styles and themes) is stored in local
files.
The following are the general steps for creating and using a catalog data source:
1.
Export the Necessary Metadata from an Oracle Database
2.
Export the Necessary Spatial Tables
3.
Edit the Map Visualizer Configuration File to Add the Catalog Data Source
4.
Restart the Map Visualizer Server
•
Export the Necessary Metadata from an Oracle Database
•
Export the Necessary Spatial Tables
•
Edit the Map Visualizer Configuration File to Add the Catalog Data Source
•
Restart the Map Visualizer Server
2.5.1.1 Export the Necessary Metadata from an Oracle Database
Before creating a catalog data source, you must use the Map Builder utility to export
the metadata to USER_SDO_CACHED_MAPS.xml, USER_SDO_THEMES.xml, and
USER_SDO_STYLES.xml files. The following considerations apply:
•
Only external tile layers are supported in catalog data source. So, the tile layers
exported into USER_SDO_CACHED_MAPS.xml must be external tile layers, such
as Bing Maps or Oracle eLocation map services.
•
All styles needed by the themes in USER_SDO_THEMES.xml must be exported in
to the USER_SDO_STYLES.xml file.
•
You need note all required spatial data tables (themes' base tables from which to
fetch spatial data) used by all of the exported themes, so that you can export each
base table into a GeoJSON file (explained in Export the Necessary Spatial
Tables).
1.
In the Map Builder utility, select Tools, then Export Metadata to XML.
2.
Select a temporary directory to store the metadata.
3.
Accept the default prefix (USER_SDO_) for the table names.
4.
Select the tile layers, themes, and styles to export. (If you are not sure which
styles are needed for the desired themes, you may export all styles.)
5.
Click OK to perform the export operation.
The USER_SDO_CACHED_MAPS.xml, USER_SDO_THEMES.xml, and USER_SDO_STYLES.xml files
are created in the specified directory.
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2.5.1.2 Export the Necessary Spatial Tables
For a catalog data source, the spatial data sets are stored in GeoJSON files. One
GeoJSON file corresponds to one spatial table is the database. To export spatial
tables, you send requests to the map visualizer server.
For example, if a spatial table called OBIEE_COUNTRY is needed by a catalog data
source theme (assume that the theme is also called OBIEE_COUNTRY) in the
USER_SDO_THEMES.xml file, then this spatial table needs to be exported as a GeoJSON
file. As a convention, you may name it with the same name as the name of the spatial
table. In this case, it is named as OBIEE_CONTRY.json.
1.
Check the themes definition from the USER_SDO_THEMES.xml file. For example, if a
theme named OBIEE_COUNTRY uses the OBIEE_COUNTRY spatial table, then
the spatial table needs to be exported. The table's columns and expected names
must be identified, and the column names are the same as the name attributes in
the theme definition. In the following example, the ISO_COUNTRY_CODE column
is mapped as Country Code:
<theme>
<name>OBIEE_COUNTRY</name>
<description><![CDATA[OBIEE Country]]></description>
<base_table>OBIEE_COUNTRY</base_table>
<geometry_column>GEOMETRY</geometry_column>
<styling_rules><![CDATA[<?xml version="1.0" standalone="yes"?><styling_rules>
<hidden_info>
<field column="ISO_COUNTRY_CODE" name="Country Code"/>
<field column="NAME" name="Country Name"/>
<field column="NAME_INIT" name="Country Name (Init)"/>
</hidden_info>
<rule>
<features style="C.AIRPORTS"> </features>
<label column="NAME_LABEL" style="T.COUNTRY_NAME_10"> 1 </label>
</rule>
</styling_rules>]]></styling_rules>
</theme>
. . .
2.
Identify the spatial table columns. In the following example, base table
OBIEE_COUNTRY has the spatial geometry column named GEOMETRY:
SQL> describe obiee_country
Name
Null?
----------------------------- -------NAME
NAME_INIT
OBIEE_LOWER
ISO_COUNTRY_CODE
SQKM
NAME_LABEL
GEOMETRY
3.
Type
---------------------------VARCHAR2(255 CHAR)
VARCHAR2(1020 CHAR)
VARCHAR2(1020 CHAR)
VARCHAR2(5)
NUMBER(11)
VARCHAR2(255 CHAR)
MDSYS.SDO_GEOMETRY
Create request strings to the map visualizer data server. For example, if
OBIEE_COUNTRY is the base table, and if the map visualizer is running at
localhost:8080, and if the data source name is my_ds_name with spatial data
retrieval enabled, you can send a request string like the following:
http://localhost:8080/ mapviewer/dataserver/my_ds_name?
t=obiee_country&sql=select iso_country_code as id, iso_country_code as "country
Code", name as "Country Name", name_init as "Country Name (Init)", name_label,
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geometry from
obiee_country&id_col=id&simplify=true&threshold=90&include_label_box=true
You can save the data set with a name OBIEE_COUNTRY.json in this case to the
temporary folder where the exported metadata (the USER_SDO_CACHED_MAPS.xml,
USER_SDO_THEMES.xml, and USER_SDO_STYLES.xml files) is stored.
2.5.1.3 Edit the Map Visualizer Configuration File to Add the Catalog Data
Source
Edit the mapViewerConfig.xml file and add the catalog data source. For example:
<map_data_source name="catalogds1"
catalog_dir="../catalogs/datafolder1"
private="true"
number_of_mappers="3"
allow_jdbc_theme_based_foi="true"
editable="false"/>
For the preceding catalog data source definition, you must create the specified
catalog_dir folder relative to where the mapViewerConfig.xml file is stored, and then
copy all data files into the folder: that is, the three exported metadata files
(USER_SDO_CACHED_MAPS.xml, USER_SDO_THEMES.xml, and USER_SDO_STYLES.xml) and all
exported GeoJSON files, such as OBIEE_COUNTRY.json in this example.
2.5.1.4 Restart the Map Visualizer Server
Restart the map visualizer server.
After the map visualizer server is restarted, all the exported tile layers and themes
should be accessible from this catalog data source. For example, you should see a
map image if you send a map request like the following:
http://localhost:8080/mapviewer/omserver?xml_request= <?xml version="1.0"
standalone="yes"?> <map_request datasource = "catalogds1" width="1024" height="768"
format="PNG_STREAM"> <center size="200"> <geoFeature><geometricProperty
typeName="center"> <Point> <coordinates>0, 0</coordinates> </Point> </
geometricProperty></geoFeature> </center> <themes> <theme name="OBIEE_COUNTRY"> </
theme> </themes> </map_request>
2.6 How a Map Is Generated
When a map request arrives at the map visualizer server, the server picks a free
renderer associated with the master data source in the request.
This topic describes the process that the map visualizer server follows to generate a
map. In brief, the map visualizer performs the following steps:
1.
Parse and process the incoming XML map request.
2.
Prepare the data for each theme (executed in parallel).
3.
Render and label each theme.
4.
Generate final images or files.
Each map generated by the map visualizer results from its receiving a valid XML map
request. The XML map request is parsed and its content is validated. The map
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visualizer then creates any dynamic styles specified in the XML request. It builds a
theme list from all themes included in the base map (if a base map is specified), as
well as any specified predefined or JDBC themes. All individual features in the request
are grouped into a single temporary theme. In other words, after parsing the incoming
request, all data that must be shown on the map is presented in a list of themes to the
map visualizer rendering engine.
The ordering of the themes in the list is important, because it determines the order in
which the themes are rendered. All themes included in the base map (when present)
are added to the list first, followed by all specified themes (predefined or JDBC). The
theme that contains all the individual features is added as the last theme on the list.
Any other requested features of a map (such as legend, map title, or footnote), are
created and saved for rendering later.
For each theme in the request, the map visualizer then creates a separate execution
thread to prepare its data, so that preparation of the themes takes place in parallel. For
a predefined theme, this means formulating a query based on the theme's definition
and any other information, such as the current map request window. This query is sent
to the database for execution, and the result set is returned. The map visualizer
creates individual renderable objects based on the result set.
•
For predefined themes that are fully cached, no query is sent to the database,
because all renderable objects are readily available.
•
For JDBC themes, the query supplied by the user is either executed as is (when
the asis attribute value is TRUE in the JDBC theme definition) or with a spatial filter
subquery automatically applied to it. The spatial filter part is used to limit the
results of the user's query to those within the current requested window.
•
For themes that already have renderable features (such as the one containing all
individual features in a request), there is no need to create renderable objects.
After all themes for the map request have been prepared and all necessary data has
been collected, the map visualizer starts to render the map. It creates an empty new
in-memory image to hold the result map, and paints the empty image with the
necessary backgrounds (color or image). It then renders all of the themes in the theme
list.
Note:
All image or GeoRaster themes are always rendered first, regardless of their
position in the theme list. All other themes, however, are rendered in the order
in which they appear in the theme list.
For each theme, features are rendered in an order determined internally by the map
visualizer. The rendering of each feature involves invoking the drawing methods of its
rendering style. After all themes have been rendered, the labeling process starts. For
each theme whose features must be labeled with text, the map visualizer invokes
algorithms to label each feature, with the specific algorithm depending on the type of
feature (such as polygon or line).
After all themes have been rendered and (when needed) labeled, the map visualizer
plots any additional map features (such as a legend) on the internal map image. The
map visualizer then converts that image into the desired format (such as PNG or GIF)
specified in the original map request; however, for SVG maps, instead of using an
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internal image, the map visualizer initially creates an empty SVG map object, then
creates an SVG document as a result of the rendering process, and inserts it into the
map object.
2.7 Cross-Schema Map Requests
A database user can issue a map request specifying a theme that uses data
associated with another database user, to select data from tables that the other data
source user is authorized to access.
For example, assume that user SCOTT wants to issue a map request using data
associated with user MVDEMO. In general, user SCOTT must be granted SELECT
access on relevant tables owned by user MVDEMO, and the <theme> element should
generally specify any tables in schema-name.table-name format. In this example
scenario:
•
For a geometry table, grant the SELECT privilege on the geometry table of
MVDEMO to SCOTT (see Example 2-53).
•
For a GeoRaster table, grant the SELECT privilege on the GeoRaster table and
raster data table or tables of MVDEMO to SCOTT (see Example 2-54).
•
For a topology data model table, grant the SELECT privilege on the topology table,
topology column index table, and related topology information tables (topologyname_EDGE$, topology-name_NODE$, topology-name_FACE$, topologyname_RELATION$) of MVDEMO to SCOTT (see Example 2-55).
•
For network data model tables, grant the SELECT privilege on the network link,
node, path, and path-link tables of MVDEMO to SCOTT (see Example 2-56).
Example 2-53 shows a dynamic theme that accesses the MVDEMO.STATES
geometry table from a data source defined on the SCOTT user.
Example 2-54 shows a dynamic theme that accesses the
MVDEMO.GEORASTER_TABLE GeoRaster table and its RDT from a data source
defined on the SCOTT user. Specify the base (GeoRaster) table in schemaname.table-name format.
Example 2-55 shows a dynamic theme that accesses the MVDEMO.LAND_PARCELS
topology table and information tables for the CITY_DATA topology from a data source
defined on the SCOTT user. Specify the feature table and the topology in schemaname.object-name format, if they are owned by a different schema than the one
associated with the data source.
In Example 2-55, you must grant SELECT on the topology column index table name
(<topology-column-index-table-name>) because the spatial index table associated with
the feature table topology column is used by the map visualizer in topology queries.
You can determine the topology column index table name as follows. Assume the
following information:
•
Topology feature table owner: MVDEMO
•
Topology feature table name: LAND_PARCELS
•
Topology feature table topology column name: FEATURE
The following query returns the index table name (in this example, MDTP_14E60$):
SQL> select sdo_index_table from all_sdo_index_info
where table_owner = 'MVDEMO'
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and table_name = 'LAND_PARCELS'
and column_name = 'FEATURE'
SDO_INDEX_TABLE
-------------------------------MDTP_14E60$
Then, modify the last GRANT statement in Example 2-55 to specify the <topologycolumn-index-table-name>. In this case:
SQL> grant select on MDTP_14E60$ to SCOTT;
Example 2-56 shows a dynamic theme that accesses the MVDEMO.BI_TEST network
and its link, node, path, and path-link tables. Specify the network name in schemaname.network-name format.
Example 2-53
Cross-Schema Access: Geometry Table
SQL> grant select on STATES to SCOTT;
. . .
<themes>
<theme name="theme1">
<jdbc_query
datasource="scottds"
spatial_column="geom"
render_style="MVDEMO:C.COUNTIES"
jdbc_srid="8265"
>SELECT geom from MVDEMO.STATES</jdbc_query>
</theme>
</themes>
Example 2-54
Cross-Schema Access: GeoRaster Table
SQL> grant select on GEORASTER_TABLE to SCOTT;
SQL> grant select on RDT_GEOR1 to SCOTT;
. . .
<themes>
<theme name="georaster_theme">
<jdbc_georaster_query
georaster_table="MVDEMO.georaster_table"
georaster_column="georaster"
raster_table="rdt_geor1"
raster_id="1"
jdbc_srid="8307"
datasource="scottds"
asis="false">
</jdbc_georaster_query>
</theme>
</themes>
Example 2-55
Cross-Schema Access: Topology Feature Table
SQL> grant select on CITY_DATA_FACE$ to SCOTT;
SQL> grant select on CITY_DATA_EDGE$ to SCOTT;
SQL> grant select on CITY_DATA_NODE$ to SCOTT;
SQL> grant select on CITY_DATA_RELATION$ to SCOTT;
SQL> grant select on LAND_PARCELS to SCOTT;
SQL> grant select on <topology-column-index-table-name> to SCOTT;
. . .
<themes>
<theme name="topo_theme" >
<jdbc_topology_query
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topology_name="MVDEMO.CITY_DATA"
feature_table="MVDEMO.LAND_PARCELS"
spatial_column="FEATURE"
render_style="MVDEMO:C.COUNTIES"
jdbc_srid="0"
datasource="scottds"
asis="false">select feature from MVDEMO.land_parcels
</jdbc_topology_query>
</theme>
</themes>
Example 2-56
Cross-Schema Access: Network Tables
SQL> grant select on BI_TEST_LINK$ to SCOTT;
SQL> grant select on BI_TEST_NODE$ to SCOTT;
SQL> grant select on BI_TEST_PATH$ to SCOTT;
SQL> grant select on BI_TEST_PLINK$ to SCOTT;
. . .
<themes>
<theme name="net_theme" >
<jdbc_network_query
network_name="MVDEMO.BI_TEST"
network_level="1"
jdbc_srid="0"
datasource="scottds"
link_style="MVDEMO:C.RED"
node_style="MVDEMO:M.CIRCLE"
node_markersize="5"
asis="false">
</jdbc_network_query>
</theme>
</themes>
2.8 Workspace Manager Support in the Map Visualizer
Workspace Manager is an Oracle Database feature that lets you version-enable one
or more tables in the database.
After a table is version-enabled, users in a workspace automatically see the correct
version of database rows in which they are interested. For detailed information about
Workspace Manager, see Oracle Database Workspace Manager Developer's Guide.
You can request a map from a specific workspace, at a specific savepoint in a
workspace, or at a point close to a specific date in a workspace. The following
attributes of the <theme> element are related to support for Workspace Manager:
•
workspace_name attribute: specifies the name of the workspace from which to get
the map data.
•
workspace_savepoint attribute: specifies the name of the savepoint to go to in the
specified workspace.
•
workspace_date attribute: specifies the date to go to (that is, a point at or near the
specified date) in the specified workspace.
•
workspace_date_format attribute: specifies the date format. The default is
mmddyyyyhh24miss. This attribute applies only if you specified the workspace_date
attribute.
•
workspace_date_nlsparam attribute: specifies globalization support options. The
options and default are the same as for the nlsparam argument to the TO_CHAR
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function for date conversion, which is described in Oracle Database SQL
Language Reference.
•
workspace_date_tswtz attribute: specifies a Boolean value. TRUE means that the
input date is in timestamp with time zone format; FALSE (the default) means that the
input date is a date string.
The workspace_name attribute is required for the use of Workspace Manager support in
the map visualizer.
If you specify neither the workspace_savepoint nor workspace_date attribute, the map
visualizer goes to the latest version of the workspace defined. If you specify both the
workspace_savepoint and workspace_date attributes, the map visualizer uses the
specified date instead of the savepoint name.
Example 2-57 shows the definition of a dynamic theme that uses attributes (shown in
bold) related to Workspace Manager support. In this example, the map visualizer will
render the data related to workspace wsp_1 at the savepoint sp1.
The following considerations apply to the map visualizer caching of predefined themes
(explained in Caching of Predefined Themes) and the use of Workspace Managerrelated map visualizer attributes:
•
The Workspace Manager-related attributes are ignored for predefined themes if
the caching attribute is set to ALL in the <styling_rules> element for the theme.
•
No caching data is considered if you specify the workspace_name attribute.
Example 2-57
Workspace Manager-Related Attributes in a Map Request
<?xml version="1.0" standalone="yes"?>
<map_request
. . .
<themes>
<theme name="wmtheme" user_clickable="false"
workspace_name="wsp_1" workspace_savepoint="sp1" >
<jdbc_query
spatial_column="GEOM"
render_style="stylename"
jdbc_srid="8307"
datasource="mvdemo"
asis="false"> select GEOM,ATTR from GEOM_TABLE
</jdbc_query>
</theme>
</themes>
. . .
</map_request>
2.9 Map Visualizer Metadata Views
The mapping metadata describing base maps, themes, and styles is stored in the
global tables SDO_MAPS_TABLE, SDO_THEMES_TABLE, and
SDO_STYLES_TABLE, which are owned by MDSYS.
However, you should never directly update these tables. Each map visualizer user has
the following views available in the schema associated with that user:
•
USER_SDO_STYLES and ALL_SDO_STYLES contain information about styles.
These views are described in xxx_SDO_STYLES Views.
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•
USER_SDO_THEMES and ALL_SDO_THEMES contain information about
themes. These views are described in xxx_SDO_THEMES Views.
•
USER_SDO_MAPS and ALL_SDO_MAPS contain information about base maps.
These views are described in xxx_SDO_MAPS Views.
•
USER_SDO_CACHED_MAPS and ALL_SDO_CACHED_MAPS contain
information about configuration settings for map tile layers. These views are
described in xxx_SDO_CACHED_MAPS Views.
Note:
You can use the Map Builder tool (described in Oracle Map Builder Tool) to
manage most mapping metadata. However, for some features you must use
SQL statements to update the map visualizer metadata views.
The USER_SDO_xxx views contain metadata information about mapping elements
(styles, themes, base maps, cached maps) owned by the user (schema), and the
ALL_SDO_xxx views contain metadata information about mapping elements on which
the user has SELECT permission.
The ALL_SDO_xxx views include an OWNER column that identifies the schema of the
owner of the object. The USER_SDO_xxx views do not include an OWNER column.
All styles defined in the database can be referenced by any user to define that user's
themes, markers with a text style, or advanced styles. However, themes and base
maps are not shared among users; so, for example, you cannot reference another
user's themes in a base map that you create.
The following rules apply for accessing the mapping metadata:
•
If you need to add, delete, or modify any metadata, you must perform the
operations using the USER_SDO_xxx views. The ALL_SDO_xxx views are
automatically updated to reflect any changes that you make to USER_SDO_xxx
views.
•
If you need only read access to the metadata for all styles, you should use the
ALL_SDO_STYLES view. Both the OWNER and NAME columns make up the
primary key; therefore, when you specify a style, be sure to include both the
OWNER and NAME.
The preceding map visualizer metadata views are defined in the following file:
$ORACLE_HOME/lbs/admin/mapdefinition.sql
The map visualizer also uses some other metadata views, which may be defined in
other files. You should never modify the contents of these views, which include the
following:
•
MDSYS.USER_SDO_TILE_ADMIN_TASKS includes information about long tasks
related to map tile management. If you stop a long map tile layer task such as
prefetching and then restart the task, the map visualizer uses the information in
the USER_SDO_TILE_ADMIN_TASKS view to resume the task rather than start
over at the beginning.
•
xxx_SDO_STYLES Views
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•
xxx_SDO_THEMES Views
•
xxx_SDO_MAPS Views
•
xxx_SDO_CACHED_MAPS Views
2.9.1 xxx_SDO_STYLES Views
The USER_SDO_STYLES and ALL_SDO_STYLES views have the columns listed in
Table 2-3.
Table 2-3
xxx_SDO_STYLES Views
Column Name
Data Type
Description
OWNER
VARCHAR2
Schema that owns the style (ALL_SDO_STYLES only)
NAME
VARCHAR2
Unique name to be associated with the style
TYPE
VARCHAR2
One of the following values: COLOR, MARKER, LINE,
AREA, TEXT, or ADVANCED
DESCRIPTION VARCHAR2
Optional descriptive text about the style
DEFINITION
CLOB
XML definition of the style
IMAGE
BLOB
Image content (for example, airport.gif) for marker or area
styles that use image-based symbols (for markers) or fillers
(for areas)
GEOMETRY
SDO_GEOME (Reserved for future use)
TRY
Depending on the Oracle Database release, the ALL_SDO_STYLES view may contain
sample styles owned by the MDSYS schema. If these styles are defined on your
system, you can specify them in theme definitions and map requests, and you can
examine the XML definitions for ideas to use in defining your own styles.
To specify a style (or other type of map visualizer object) that is owned by a schema
other than the one for the current user, you must specify the schema name, and you
must use a colon (:), not a period, between the schema name and the object name.
The following excerpt from a <jdbc_query> element refers to the style named C.RED
owned by the MDSYS schema:
<jdbc_query . . . render_style="MDSYS:C.RED">
. . .
</jdbc_query>
Example 2-58 finds the names of all currently defined styles owned by the MDSYS
schema, and it displays the type, description, and XML definition of one of the styles.
(The example output is reformatted for readability.)
Example 2-58
Finding Styles Owned by the MDSYS Schema
SELECT owner, name FROM all_sdo_styles
WHERE owner = 'MDSYS';
OWNER
-------------------------------MDSYS
MDSYS
MDSYS
MDSYS
NAME
-------------------------------C.BLACK
C.BLACK GRAY
C.BLUE
C.COUNTIES
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MDSYS
. . .
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
. . .
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
MDSYS
. . .
C.FACILITY
L.MAJOR STREET
L.MAJOR TOLL ROAD
L.MQ_ROAD2
L.PH
L.POOR_ROADS
L.PTH
L.RAILROAD
L.RAMP
L.SH
L.STATE BOUNDARY
M.REDSQ
M.SMALL TRIANGLE
M.STAR
M.TOWN HALL
M.TRIANGLE
T.AIRPORT NAME
T.CITY NAME
T.MAP TITLE
T.PARK NAME
T.RED STREET
T.ROAD NAME
T.SHIELD1
T.SHIELD2
T.STATE NAME
T.STREET NAME
-- Display the type, description, and XML definition of one style.
SET LONG 4000;
SELECT owner, name, type, description, definition
FROM all_sdo_styles WHERE name = 'L.PH';
OWNER NAME
------ ----MDSYS L.PH
TYPE
-----LINE
DESCRIPTION
-----------------Primary highways
DEFINITION
--------------------------------------------------------------------------<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<desc></desc>
<g class="line" style="fill:#33a9ff;stroke-width:4">
<line class="parallel" style="fill:#aa55cc;stroke-width:1.0"/>
</g>
</svg>
2.9.2 xxx_SDO_THEMES Views
The USER_SDO_THEMES and ALL_SDO_THEMES views have the columns listed in
Table 2-4.
Table 2-4
xxx_SDO_THEMES Views
Column Name
Data Type
Description
OWNER
VARCHAR2
Schema that owns the theme (ALL_SDO_THEMES only)
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Table 2-4
(Cont.) xxx_SDO_THEMES Views
Column Name
Data Type
Description
NAME
VARCHAR2
Unique name to be associated with the theme
DESCRIPTION
VARCHAR2
Optional descriptive text about the theme
BASE_TABLE
VARCHAR2
Table or view containing the spatial geometry column
GEOMETRY_C
OLUMN
VARCHAR2
Name of the spatial geometry column (of type
SDO_GEOMETRY)
STYLING_RULE CLOB
S
XML definition of the styling rules to be associated with the
theme
2.9.3 xxx_SDO_MAPS Views
The USER_SDO_MAPS and ALL_SDO_MAPS views have the columns listed in
Table 2-5.
Table 2-5
xxx_SDO_MAPS Views
Column Name
Data Type
Description
OWNER
VARCHAR2
Schema that owns the base map (ALL_SDO_MAPS only)
NAME
VARCHAR2
Unique name to be associated with the base map
DESCRIPTION
VARCHAR2
Optional descriptive text about the base map
DEFINITION
CLOB
XML definition of the list of themes and their scale value
range information to be associated with the base map
2.9.4 xxx_SDO_CACHED_MAPS Views
The USER_SDO_MAPS and ALL_SDO_MAPS views have the columns listed in
Table 2-6.
Table 2-6
xxx_SDO_CACHED_MAPS Views
Column Name
Data Type
Description
NAME
VARCHAR2
Unique name of the cached map source
DESCRIPTION
VARCHAR2
Optional descriptive text about the cached map source
TILES_TABLE
VARCHAR2
(Not currently used)
IS_ONLINE
VARCHAR2
YES if the map tile layer is online, or NO if the map tile layer is
offline. When a tile is missing from the cache and the map
tile layer is online, the map tile server will fetch the tile and
return the fetched tile to the client. When a tile is missing and
the map tile layer is offline, the map tile server will not fetch
the tile but will return a blank image to the client.
IS_INTERNAL
VARCHAR2
YES if the map source is an internal map source, or NO if the
map source is an external map source
DEFINITION
CLOB
XML definition of the map tile layer, as described later in this
section.
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Table 2-6
(Cont.) xxx_SDO_CACHED_MAPS Views
Column Name
Data Type
Description
BASE_MAP
VARCHAR2
Name of the cached map visualizer base map, if the map
source is an internal map source
MAP_ADAPTER BLOB
The jar file that contains the adapter Java classes of the
external map services provider, as described later in this
section.
For detailed information about using the USER_SDO_CACHED_MAPS view, see Map
Tile Server Configuration.
2.10 Oracle Maps
Oracle Maps is the name for a suite of technologies for developing high-performance
interactive web-based mapping applications. It consists of components from both the
server side and the client side.
•
Overview of Oracle Maps
•
Architecture for Oracle Maps Applications
2.10.1 Overview of Oracle Maps
Oracle Maps consists of the following main components:
•
A map tile server that caches and serves pregenerated map image tiles upon a
map image tile request
•
A map server that generates maps form spatial data to the mapping client upon a
client map image request
•
A map data server that fetches spatial data from a spatial data provider to the
mapping client
•
An Ajax-based JavaScript mapping client. (Ajax is an acronym for asynchronous
JavaScript and XML.) This client provides functions for browsing and interacting
with maps, as well as a flexible application programming interface (API).
The map tile server (map image caching engine, described in Map Tile Server)
automatically fetches and caches map image tiles rendered by the Oracle Spatial and
Graph map visualizer or other web-enabled map providers. It also serves cached map
image tiles to the clients, which are web applications developed using the Oracle Maps
client API. The clients can then automatically stitch multiple map image tiles into a
seamless large map. Because the map image tiles are normally pregenerated and
cached, the application users will experience fast map viewing performance.
The JavaScript mapping client is a browser side map display engine that fetches map
content from the servers, and presents it to client applications. It:
•
Fetches map images tiles from a map visualizer server, from a third party map
service provider, or from its local disk-storage
•
Retrieves spatial data from a map visualizer server, from a third party spatial data
provider, or from its local disk-storage and then renders the spatial data into map
images by itself on the client side
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•
Provides customizable map-related user interaction controls, such as map
dragging and clicking, for the application
•
Provides other built-in features and utilities to customize the map contents and
map layout design
The JavaScript mapping client can be easily integrated with any web application or
portal.
2.10.2 Architecture for Oracle Maps Applications
Figure 2-15 shows the architecture of web mapping applications that are developed
using Oracle Maps.
Figure 2-15
Architecture for Oracle Maps Applications
Referring to Figure 2-15, applications interact with the Oracle Maps architecture as
follows:
•
The application is developed using JavaScript, and it runs inside the JavaScript
engine of the web browser.
•
The application invokes the JavaScript map client to fetch the map image tiles
from the map tile server, and then it displays the map in the web browser.
•
The application invokes the JavaScript map client to fetch the map image in other
form of map services (such as WMS and WMTS) from the server and then
displays the map image.
•
The application invokes the JavaScript map client to fetch spatial data from the
map data server and then renders the map image to display.
•
The JavaScript map client controls map-related user interaction for the application.
•
When the map visualizer server receives a map image request, the request can be
one of its several supported types: a map image tile request to its map tile server,
a map image request to its map server, a WMS map request to its WMS server, or
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a WMTS map image tile request to its WMTS server. Each request will be handled
by the server accordingly.
Example 1: When the map tile server receives a map image tile request, it first
checks to see if the requested tile is already cached. If the tile is already in the
cache, the cached tile is then returned to the client. If the tile is not in the cache,
then the map tile server fetches the tile into the cache and returns it to the client.
Tiles can be fetched either directly from the map visualizer map rendering engine
or from an external web map service provider.
Example 2: When the server receives a map image request (instead of a map tile
request) to its map server, the map server renders the image and returns it to the
client. Note that in contrast to the map tile server, the map server generates a map
according to a specified data bounds and renders the data onto an image with
specified dimension, but it does not cache the map image.
•
When the map data server receives a map data request, it retrieves the spatial
data and returns the spatial data, not map images, to the client.
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Map Visualization Servers
The map visualizer, as a set of Java Enterprise Edition packages, contains a collection
of servers to provide mapping services.
These services include a map server, a map data server, a map tile server, a WMS
server (see OGC WMS Support in the Map Visualization Component), and a WMTS
server (see OGC WMTS Support in the Map Visualization Component).When you
develop Oracle Maps applications, the Oracle Maps API and the map visualizer server
will identify the needed service and then issue map service request to the proper
server. You normally do not need to send service requests explicitly in your map
applications; however, if you are familiar with the map visualizer servers described in
this chapter, it can help if you need to debug or optimize the application.
Topics:
•
Map Visualizer Map Data Server
The map visualizer map data server provides services for streaming live data from
a database server to a client.
•
Map Tile Server
The map tile server is a map image caching engine that fetches, caches, and
serves pregenerated, fixed-size map image tiles.
3.1 Map Visualizer Map Data Server
The map visualizer map data server provides services for streaming live data from a
database server to a client.
The data can be consumed by the Oracle Maps JavaScript API client, or be edited by
the API editing utilities. It is also used as the middle-tier component for handling data
synchronization tasks.
At the most basic level, a client sends a request to the map data server, specifying the
name of a theme and an optional bounding box. The server then returns the live data
(including both geometries and attributes) in compressed GeoJSON format.
•
Domains and Map Data Server URL Patterns
•
Map Data Server Request Parameters
•
Interpreting Data Returned from the Map Data Server
•
Map Data Server Error Handling
3.1.1 Domains and Map Data Server URL Patterns
The map data server uses domains, where each domain corresponds to a map
visualizer data source. For example, to request data from the mvdemo data source, the
URL must have the following pattern:
http://example.com:8080/mapviewer/dataserver/mvdemo?
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In this URL request, /dataserver refers to the map data server. /mvdemo is the path
information, which indicates which domain or data source this request is directed
against. There is no need to specify the data source explicitly in the rest of the URL
request. This URL pattern provides flexibility in terms of protection. A user or a web
administrator can easily set up different levels of protection for different domains using
such a URL pattern.
To get a quick help regarding the full list of supported HTTP request parameters, you
can issue a request that includes the help parameter. For example:
http://example:8080/mapviewer/dataserver/mvdemo?help=true
This example returns a list of supported parameters. (Note that the /mvdemo path is still
required even for this help request.)
3.1.2 Map Data Server Request Parameters
In a map data server request to get data, the URL must include appropriate query
parameters. The data could be from a map visualizer predefined geometry theme or
JDBC theme.
•
Getting Data from a Predefined Geometry Theme
•
Getting Data from a JDBC Theme
•
Getting Annotation Text from a JDBC Theme
•
Getting Topology Data
3.1.2.1 Getting Data from a Predefined Geometry Theme
Before getting data from a predefined geometry theme, be sure that the predefined
geometry theme is properly defined. If it is not properly defined, modify its definition or
create a new predefined geometry theme with the proper definition.
Besides the geometry column of a spatial table, if you also need some attribute
columns for an application, then your geometry theme's STYLING_RULES column
must have the <hidden_info> element for defining needed attributes. For example, if
your application needs a geometry theme (such as CUSTOMERS) to represent a
spatial table, and if you also need each customer's name, city, and sales amount, then
the STYLING_RULES should look similar to the following:
SQL> select STYLING_RULES from user_sdo_themes where name='CUSTOMERS';
STYLING_RULES
-------------------------------------------------------------------------------<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="name" name="Name"/>
<field column="city" name="City"/>
<field column="sales" name="Sales"/>
</hidden_info>
<rule>
<features style="M.STOPLIGHT_RED"> </features>
</rule>
</styling_rules>
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The Map Builder utility is the recommended tool for modifying or creating geometry
themes.
For information using styling rules in a predefined geometry theme, see Styling Rules
in Predefined Spatial Geometry Themes.
The following parameters are available for a map data server request to get data from
a map visualizer predefined geometry theme. The t (theme name) parameter is
required; the others are optional.
•
t: Name of the theme.
•
bbox: Bounding box. Must be a comma-delimited list of minx,miny,maxx,maxy.
•
to_srid: SRID (spatial reference system) in which to return the data.
•
bbox_srid: SRID (spatial reference system) of the bounding box, if different from
the native SRID of the data.
•
seq: Sequence ID, to be used when getting data in multipart format.
•
dadp: Digits after decimal point: the maximum number of digits after the decimal
point for the coordinates in the returned data.
•
include_style_info: Determines whether styling information (rendering/labeling
style name and related columns) should be included with each feature. (The
default is true.)
•
include_label_box: Determines whether a label box should be included with each
polygon feature. (The default is true.) A label box is a near maximum rectangle
inside the polygon. A label placed inside this rectangle is guaranteed to be
completely inside the polygon feature. This parameter is ignored for non-polygon
features.
The following are some examples.
To get all the data from the CITIES table in the 3857 SRID:
http://example:8080/mapviewer/dataserver/mvdemo?t=theme_demo_cities&to_srid=3857
To get all the data from the CITIES table that interacts with a specified bbox in 3857
SRID:
http://example:8080/mapviewer/dataserver/mvdemo?
t=theme_demo_cities&bbox=-122.0,25,-100,45&to_srid=3857
To get all the data from the CITIES table that interacts with a specified bbox in 3857
SRID, with 3 digits after the decimal points, and without styling information:
http://example:8080/mapviewer/dataserver/mvdemo?
t=theme_demo_cities&bbox=-122.0,25,-100,45&to_srid=3857&dadp=3&include_style_info=
no
To get all data from the COUNTIES table and include label boxes:
http://example:8080/mapviewer/dataserver/mvdemo?
t=theme_demo_counties&include_label_box=yes
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3.1.2.2 Getting Data from a JDBC Theme
The following parameters are available for a map data server request to get data from
a map visualizer theme based on a dynamic JDBC theme. The t (theme name) and
sql (SQL query) parameters are required; the others are optional.
•
t: Name of the theme.
•
sql: The complete SQL query, properly URL encoded.
•
asis: Determines whether the query should be executed "as is". The default is
false, which causes the map visualizer to embed the SQL query as a subquery of
its spatial filter query. If the value is true, the map visualizer does not attempt to
modify the supplied query string.
•
bbox: Bounding box. Must be a comma-delimited list of minx,miny,maxx,maxy.
•
to_srid: SRID (spatial reference system) in which to return the data.
•
bbox_srid: SRID (spatial reference system) of the bounding box, if different from
the native SRID of the data.
•
seq: Sequence ID, to be used when getting data in multipart format.
•
dadp: Digits after decimal point: the maximum number of digits after the decimal
point for the coordinates in the returned data.
•
include_style_info: Determines whether styling information (rendering/labeling
style name and related columns) should be included with each feature. (The
default is true.)
•
include_label_box: Determines whether a label box should be included with each
polygon feature. (The default is true.) A label box is a near maximum rectangle
inside the polygon. A label placed inside this rectangle is guaranteed to be
completely inside the polygon feature. This parameter is ignored for non-polygon
features.
The following are some examples.
To get all the data of the CITIES table in SRID 3857:
http://example:8080/mapviewer/dataserver/mvdemo?t=theme1&sql=select+*+from
+cities&to_srid=3857
To get all the data of the table CITIES within a given bbox in SRID 3857:
http://example:8080/mapviewer/dataserver/mvdemo?t=theme1&sql=select+*+from
+cities&to_srid=3857&bbox=-122.0,25,-100,45
To run the query as is, without a bbox and return data in SRID 3857:
http://example:8080/mapviewer/dataserver/mvdemo?t=theme1&sql=select+*+from
+cities&to_srid=3857&bbox=-122.0,25,-100,45&asis=t
3.1.2.3 Getting Annotation Text from a JDBC Theme
A request to retrieve annotation text elements from a JDBC theme is similar to that in
Getting Data from a JDBC Theme
The following parameters are available for a map data server request to get data from
a map visualizer theme based on a dynamic JDBC theme. The t (theme name), sql
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(SQL query, geom_type, and base_table parameters are required; the others are
optional.
•
t: Name of the theme.
•
sql: The complete SQL query, properly URL encoded.
•
geom_type: Must be specified as annotation to indicate that the spatial column is on
annotation type.
•
base_table: The database table (for the server to read annotation text metadata
information for that table).
•
asis: Determines whether the query should be executed "as is". The default is
false, which causes the map visualizer to embed the SQL query as a subquery of
its spatial filter query. If the value is true, the map visualizer does not attempt to
modify the supplied query string.
•
bbox: Bounding box. Must be a comma-delimited list of minx,miny,maxx,maxy.
•
to_srid: SRID (spatial reference system) in which to return the data.
•
bbox_srid: SRID (spatial reference system) of the bounding box, if different from
the native SRID of the data.
•
seq: Sequence ID, to be used when getting data in multipart format.
•
dadp: Digits after decimal point: the maximum number of digits after the decimal
point for the coordinates in the returned data.
•
include_style_info: Determines whether styling information (rendering/labeling
style name and related columns) should be included with each feature. (The
default is true.)
•
include_label_box: Determines whether a label box should be included with each
polygon feature. (The default is true.) A label box is a near maximum rectangle
inside the polygon. A label placed inside this rectangle is guaranteed to be
completely inside the polygon feature. This parameter is ignored for non-polygon
features.
The following example retrieves annotation text information:
http://example:8080/mapviewer/dataserver/tilsmenv?t=theme1&sql=select+*+from
+annotext_table&geom_col=textobj&geom_type=annotation&base_table=annotext_table&bb
ox=0,0,10,10
A typical response includes the annotation text table metadata information plus the
annotation text feature. Each annotation text feature can have one or more text
elements. Each text element can be defined by a text value, a location, a leader line,
and graphic attributes. Refer to OGC specification of annotation texts for additional
information.
The response looks like the following:
{"type":"AnnotationText",
"collectionName":"theme1",
"srs":0,
"geodetic":false,
"bbox":[0, 0, 10, 10],
"attr_names":["ID"],
"attr_types":["double"],
"default_text_attributes":
{"fontWeight":"Normal","fontStyle":"Normal","textDecoration":"None","letterSpacing":"
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Normal","wordSpacing":"Normal","fill":"black","fill-opacity":
1.0,"stroke":"black","strokeWidth":1.0,"stroke-opacity":
1.0,"horizontalAlignment":"start","verticalAlignment":"top","multilineJustification":
"left","multilineSpacing":0.0},
"metadata":{"textExpression":"name","textAttributes":
{"fontFamily":"Serif","fontSize":14.0,"fill":"#ff0000"}},
"features":[
{"type":"AnnoText", "elements":[{"location":{"type":"Point", "coordinates":[1,
1]},"textValue":"Sample Label 1","leaderLine":{"type":"LineString", "coordinates":
[0,0,1,1]}}],"envelope":{"type":"Rectangle", "coordinates":[0,0,1,1]},"properties":
{"ID":"1.0"}},
{"type":"AnnoText", "elements":[{"location":{"type":"LineString", "coordinates":
[2,5,4,5,6,5]},"leaderLine":{"type":"LineString", "coordinates":
[4,3,4,5]},"textAttributes":{"fontFamily":"Dialog","fontSize":
14.0,"fill":"blue"}}],"envelope":{"type":"Rectangle", "coordinates":
[2,3,6,5]},"properties":{"ID":"3.0"}},
{"type":"AnnoText", "elements":[{"location":{"type":"Point", "coordinates":[10,
10]},"textValue":"Sample Label 2","leaderLine":{"type":"LineString", "coordinates":
[5,10,10,10]}}],"envelope":{"type":"LineString", "coordinates":
[5,10,10,10]},"properties":{"ID":"2.0"}}
]}
3.1.2.4 Getting Topology Data
A topology set is defined by a set of topology primitives (faces, edges, and nodes(.
Each topology feature can be associated with one or more topology primitives.
A request to retrieve the topology primitives must contain the topology parameter, as in
the following example:
http://example:8080/mapviewer/dataserver/tilsmenv?
topology=city_data&bbox=10,10,35,35
The response includes all primitives that interact with input MBR:
{"type":"TopologyPrimitives",
"topology":"city_data",
"srs":0,
"bbox":[0, 0, 62, 42],
"face_attr_names":
["FACE_ID","BOUNDARY_EDGE_ID","ISLAND_EDGE_ID_LIST","ISLAND_NODE_ID_LIST"],
"face_attr_types":["integer","integer","array:integer","array:integer"],
"edge_attr_names":
["EDGE_ID","START_NODE_ID","END_NODE_ID","NEXT_LEFT_EDGE_ID","PREV_LEFT_EDGE_ID","NEX
T_RIGHT_EDGE_ID","PREV_RIGHT_EDGE_ID","LEFT_FACE_ID","RIGHT_FACE_ID"],
"edge_attr_types":
["integer","integer","integer","integer","integer","integer","integer","integer","int
eger"],
"node_attr_names":["NODE_ID","EDGE_ID","FACE_ID"],
"node_attr_types":["integer","integer","integer"],
"primitives":[
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[3,30,15,38]},
"properties":{"FACE_ID":"1", "BOUNDARY_EDGE_ID":"1", "ISLAND_EDGE_ID_LIST":[25]}},
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[9,14,21,22]},
"properties":{"FACE_ID":"3", "BOUNDARY_EDGE_ID":"19"}},
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[9,6,21,14]},
"properties":{"FACE_ID":"6", "BOUNDARY_EDGE_ID":"20"}},
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[17,30,31,40]},
"properties":{"FACE_ID":"2", "BOUNDARY_EDGE_ID":"2", "ISLAND_NODE_ID_LIST":[4]}},
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[21,6,35,14]},
"properties":{"FACE_ID":"7", "BOUNDARY_EDGE_ID":"10"}},
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{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[21,14,35,22]},
"properties":{"FACE_ID":"4", "BOUNDARY_EDGE_ID":"17"}},
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[35,14,47,22]},
"properties":{"FACE_ID":"5", "BOUNDARY_EDGE_ID":"15"}},
{"type":"Face", "mbr_geometry":{"type":"Rectangle", "coordinates":[35,6,47,14]},
"properties":{"FACE_ID":"8", "BOUNDARY_EDGE_ID":"16"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":
[8,30,16,30,16,38,3,38,3,30,8,30]}, "properties":{"EDGE_ID":"1",
"START_NODE_ID":"1", "END_NODE_ID":"1", "NEXT_LEFT_EDGE_ID":"1",
"PREV_LEFT_EDGE_ID":"1", "NEXT_RIGHT_EDGE_ID":"-1", "PREV_RIGHT_EDGE_ID":"-1",
"LEFT_FACE_ID":"1", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":
[4,31,7,31,7,34,4,34,4,31]}, "properties":{"EDGE_ID":"26", "START_NODE_ID":"20",
"END_NODE_ID":"20", "NEXT_LEFT_EDGE_ID":"26", "PREV_LEFT_EDGE_ID":"26",
"NEXT_RIGHT_EDGE_ID":"-26", "PREV_RIGHT_EDGE_ID":"-26", "LEFT_FACE_ID":"9",
"RIGHT_FACE_ID":"1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[9,22,21,22]},
"properties":{"EDGE_ID":"6", "START_NODE_ID":"16", "END_NODE_ID":"17",
"NEXT_LEFT_EDGE_ID":"7", "PREV_LEFT_EDGE_ID":"21", "NEXT_RIGHT_EDGE_ID":"-21",
"PREV_RIGHT_EDGE_ID":"19", "LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"3"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[9,14,9,22]},
"properties":{"EDGE_ID":"21", "START_NODE_ID":"15", "END_NODE_ID":"16",
"NEXT_LEFT_EDGE_ID":"6", "PREV_LEFT_EDGE_ID":"22", "NEXT_RIGHT_EDGE_ID":"9",
"PREV_RIGHT_EDGE_ID":"-6", "LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"3"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[9,14,21,14]},
"properties":{"EDGE_ID":"9", "START_NODE_ID":"15", "END_NODE_ID":"14",
"NEXT_LEFT_EDGE_ID":"19", "PREV_LEFT_EDGE_ID":"-21", "NEXT_RIGHT_EDGE_ID":"-22",
"PREV_RIGHT_EDGE_ID":"20", "LEFT_FACE_ID":"3", "RIGHT_FACE_ID":"6"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[9,6,21,6]},
"properties":{"EDGE_ID":"12", "START_NODE_ID":"8", "END_NODE_ID":"9",
"NEXT_LEFT_EDGE_ID":"20", "PREV_LEFT_EDGE_ID":"-22", "NEXT_RIGHT_EDGE_ID":"22",
"PREV_RIGHT_EDGE_ID":"-13", "LEFT_FACE_ID":"6", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[9,35,13,35]},
"properties":{"EDGE_ID":"25", "START_NODE_ID":"21", "END_NODE_ID":"22",
"NEXT_LEFT_EDGE_ID":"-25", "PREV_LEFT_EDGE_ID":"-25", "NEXT_RIGHT_EDGE_ID":"25",
"PREV_RIGHT_EDGE_ID":"25", "LEFT_FACE_ID":"1", "RIGHT_FACE_ID":"1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[9,6,9,14]},
"properties":{"EDGE_ID":"22", "START_NODE_ID":"8", "END_NODE_ID":"15",
"NEXT_LEFT_EDGE_ID":"21", "PREV_LEFT_EDGE_ID":"-12", "NEXT_RIGHT_EDGE_ID":"12",
"PREV_RIGHT_EDGE_ID":"-9", "LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"6"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":
[25,30,31,30,31,40,17,40,17,30,25,30]}, "properties":{"EDGE_ID":"2",
"START_NODE_ID":"2", "END_NODE_ID":"2", "NEXT_LEFT_EDGE_ID":"3",
"PREV_LEFT_EDGE_ID":"-3", "NEXT_RIGHT_EDGE_ID":"-2", "PREV_RIGHT_EDGE_ID":"-2",
"LEFT_FACE_ID":"2", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[21,6,35,6]},
"properties":{"EDGE_ID":"13", "START_NODE_ID":"9", "END_NODE_ID":"10",
"NEXT_LEFT_EDGE_ID":"18", "PREV_LEFT_EDGE_ID":"-20", "NEXT_RIGHT_EDGE_ID":"-12",
"PREV_RIGHT_EDGE_ID":"-14", "LEFT_FACE_ID":"7", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[21,22,35,22]},
"properties":{"EDGE_ID":"7", "START_NODE_ID":"17", "END_NODE_ID":"18",
"NEXT_LEFT_EDGE_ID":"8", "PREV_LEFT_EDGE_ID":"6", "NEXT_RIGHT_EDGE_ID":"-19",
"PREV_RIGHT_EDGE_ID":"17", "LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"4"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[21,6,21,14]},
"properties":{"EDGE_ID":"20", "START_NODE_ID":"9", "END_NODE_ID":"14",
"NEXT_LEFT_EDGE_ID":"-9", "PREV_LEFT_EDGE_ID":"12", "NEXT_RIGHT_EDGE_ID":"13",
"PREV_RIGHT_EDGE_ID":"10", "LEFT_FACE_ID":"6", "RIGHT_FACE_ID":"7"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[35,14,21,14]},
"properties":{"EDGE_ID":"10", "START_NODE_ID":"13", "END_NODE_ID":"14",
"NEXT_LEFT_EDGE_ID":"-20", "PREV_LEFT_EDGE_ID":"18", "NEXT_RIGHT_EDGE_ID":"17",
"PREV_RIGHT_EDGE_ID":"-19", "LEFT_FACE_ID":"7", "RIGHT_FACE_ID":"4"}},
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{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[21,14,21,22]},
"properties":{"EDGE_ID":"19", "START_NODE_ID":"14", "END_NODE_ID":"17",
"NEXT_LEFT_EDGE_ID":"-6", "PREV_LEFT_EDGE_ID":"9", "NEXT_RIGHT_EDGE_ID":"-10",
"PREV_RIGHT_EDGE_ID":"-7", "LEFT_FACE_ID":"3", "RIGHT_FACE_ID":"4"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[25,30,25,35]},
"properties":{"EDGE_ID":"3", "START_NODE_ID":"2", "END_NODE_ID":"3",
"NEXT_LEFT_EDGE_ID":"-3", "PREV_LEFT_EDGE_ID":"2", "NEXT_RIGHT_EDGE_ID":"2",
"PREV_RIGHT_EDGE_ID":"3", "LEFT_FACE_ID":"2", "RIGHT_FACE_ID":"2"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[35,6,47,6]},
"properties":{"EDGE_ID":"14", "START_NODE_ID":"10", "END_NODE_ID":"11",
"NEXT_LEFT_EDGE_ID":"16", "PREV_LEFT_EDGE_ID":"-18", "NEXT_RIGHT_EDGE_ID":"-13",
"PREV_RIGHT_EDGE_ID":"-16", "LEFT_FACE_ID":"8", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[35,14,47,14]},
"properties":{"EDGE_ID":"11", "START_NODE_ID":"13", "END_NODE_ID":"12",
"NEXT_LEFT_EDGE_ID":"15", "PREV_LEFT_EDGE_ID":"-17", "NEXT_RIGHT_EDGE_ID":"-18",
"PREV_RIGHT_EDGE_ID":"16", "LEFT_FACE_ID":"5", "RIGHT_FACE_ID":"8"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[35,6,35,14]},
"properties":{"EDGE_ID":"18", "START_NODE_ID":"10", "END_NODE_ID":"13",
"NEXT_LEFT_EDGE_ID":"10", "PREV_LEFT_EDGE_ID":"13", "NEXT_RIGHT_EDGE_ID":"14",
"PREV_RIGHT_EDGE_ID":"-11", "LEFT_FACE_ID":"7", "RIGHT_FACE_ID":"8"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[35,22,47,22]},
"properties":{"EDGE_ID":"8", "START_NODE_ID":"18", "END_NODE_ID":"19",
"NEXT_LEFT_EDGE_ID":"-15", "PREV_LEFT_EDGE_ID":"7", "NEXT_RIGHT_EDGE_ID":"-17",
"PREV_RIGHT_EDGE_ID":"15", "LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"5"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[35,14,35,22]},
"properties":{"EDGE_ID":"17", "START_NODE_ID":"13", "END_NODE_ID":"18",
"NEXT_LEFT_EDGE_ID":"-7", "PREV_LEFT_EDGE_ID":"-10", "NEXT_RIGHT_EDGE_ID":"11",
"PREV_RIGHT_EDGE_ID":"-8", "LEFT_FACE_ID":"4", "RIGHT_FACE_ID":"5"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":
[36,38,38,35,41,34,42,33,45,32,47,28,50,28,52,32,57,33]}, "properties":
{"EDGE_ID":"4", "START_NODE_ID":"5", "END_NODE_ID":"6", "NEXT_LEFT_EDGE_ID":"-5",
"PREV_LEFT_EDGE_ID":"-4", "NEXT_RIGHT_EDGE_ID":"4", "PREV_RIGHT_EDGE_ID":"5",
"LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":
[41,40,45,40,47,42,62,41,61,38,59,39,57,36,57,33]}, "properties":{"EDGE_ID":"5",
"START_NODE_ID":"7", "END_NODE_ID":"6", "NEXT_LEFT_EDGE_ID":"-4",
"PREV_LEFT_EDGE_ID":"-5", "NEXT_RIGHT_EDGE_ID":"5", "PREV_RIGHT_EDGE_ID":"4",
"LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[47,14,47,22]},
"properties":{"EDGE_ID":"15", "START_NODE_ID":"12", "END_NODE_ID":"19",
"NEXT_LEFT_EDGE_ID":"-8", "PREV_LEFT_EDGE_ID":"11", "NEXT_RIGHT_EDGE_ID":"-16",
"PREV_RIGHT_EDGE_ID":"8", "LEFT_FACE_ID":"5", "RIGHT_FACE_ID":"-1"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[47,6,47,14]},
"properties":{"EDGE_ID":"16", "START_NODE_ID":"11", "END_NODE_ID":"12",
"NEXT_LEFT_EDGE_ID":"-11", "PREV_LEFT_EDGE_ID":"14", "NEXT_RIGHT_EDGE_ID":"-14",
"PREV_RIGHT_EDGE_ID":"-15", "LEFT_FACE_ID":"8", "RIGHT_FACE_ID":"-1"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[4, 31]}, "properties":
{"NODE_ID":"20", "EDGE_ID":"26", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[8, 30]}, "properties":
{"NODE_ID":"1", "EDGE_ID":"1", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[9, 6]}, "properties":
{"NODE_ID":"8", "EDGE_ID":"12", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[9, 35]}, "properties":
{"NODE_ID":"21", "EDGE_ID":"25", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[9, 14]}, "properties":
{"NODE_ID":"15", "EDGE_ID":"21", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[9, 22]}, "properties":
{"NODE_ID":"16", "EDGE_ID":"6", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[13, 35]}, "properties":
{"NODE_ID":"22", "EDGE_ID":"-25", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[20, 37]}, "properties":
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{"NODE_ID":"4", "EDGE_ID":"0", "FACE_ID":"2"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[21,
{"NODE_ID":"14", "EDGE_ID":"19", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[21,
{"NODE_ID":"17", "EDGE_ID":"7", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[21,
{"NODE_ID":"9", "EDGE_ID":"20", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[25,
{"NODE_ID":"2", "EDGE_ID":"2", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[25,
{"NODE_ID":"3", "EDGE_ID":"-3", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[35,
{"NODE_ID":"13", "EDGE_ID":"17", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[35,
{"NODE_ID":"10", "EDGE_ID":"18", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[35,
{"NODE_ID":"18", "EDGE_ID":"8", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[36,
{"NODE_ID":"5", "EDGE_ID":"4", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[41,
{"NODE_ID":"7", "EDGE_ID":"5", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[47,
{"NODE_ID":"12", "EDGE_ID":"15", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[47,
{"NODE_ID":"11", "EDGE_ID":"-14", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[47,
{"NODE_ID":"19", "EDGE_ID":"-15", "FACE_ID":"0"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[57,
{"NODE_ID":"6", "EDGE_ID":"-4", "FACE_ID":"0"}}
]}
14]}, "properties":
22]}, "properties":
6]}, "properties":
30]}, "properties":
35]}, "properties":
14]}, "properties":
6]}, "properties":
22]}, "properties":
38]}, "properties":
40]}, "properties":
14]}, "properties":
6]}, "properties":
22]}, "properties":
33]}, "properties":
To retrieve topology features, the following example specifies the topology, base_table,
and geom_col parameters (where grom_col refers to the topology column):
http://example:8080/mapviewer/dataserver/tilsmenv?
topology=city_data&base_table=land_parcels&geom_col=feature
The response to this request is similar to the following:
{"type":"TopologyFeatures",
"topology":"CITY_DATA",
"topology_id":5,
"topology_owner":"TILSZUSER",
"tolerance":5.0E-5,
"srs":0,
"table_schema":"TILSZUSER",
"table_name":"LAND_PARCELS",
"topo_column":"FEATURE",
"layer_id":1,
"layer_type":"POLYGON",
"layer_level":0,
"child_layer":0,
"node_sequence":"CITY_DATA_NODE_S",
"edge_sequence":"CITY_DATA_EDGE_S",
"face_sequence":"CITY_DATA_FACE_S",
"feature_sequence":"CITY_DATA_TG_S",
"digits_right_decimal":16,
"attr_names":["FEATURE_NAME"],
"attr_types":["string"],
"features":[
{"type":"topology", "tg_id":4, "primitives":[{"topo_id":3,"topo_type":3},{"topo_id":
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6,"topo_type":3}], "properties":{"FEATURE_NAME":"P1"}},
{"type":"topology", "tg_id":5, "primitives":[{"topo_id":4,"topo_type":3},{"topo_id":
7,"topo_type":3}], "properties":{"FEATURE_NAME":"P2"}},
{"type":"topology", "tg_id":6, "primitives":[{"topo_id":5,"topo_type":3},{"topo_id":
8,"topo_type":3}], "properties":{"FEATURE_NAME":"P3"}},
{"type":"topology", "tg_id":7, "primitives":[{"topo_id":2,"topo_type":3}],
"properties":{"FEATURE_NAME":"P4"}},
{"type":"topology", "tg_id":8, "primitives":[{"topo_id":1,"topo_type":3}],
"properties":{"FEATURE_NAME":"P5"}}
]}
To specific primitive faces, edges, and nodes, the following example define the
primitive identifiers:
http://example:8080/mapviewer/dataserver/tilsmenv?
topology=city_data&face_ids=-1&edge_ids=3,4&node_ids=5
The response to this request is similar to the following:
{"type":"TopologyPrimitives",
"topology":"city_data",
"srs":0,
"bbox":[0, 0, 57, 38],
"face_attr_names":
["FACE_ID","BOUNDARY_EDGE_ID","ISLAND_EDGE_ID_LIST","ISLAND_NODE_ID_LIST"],
"face_attr_types":["integer","integer","array:integer","array:integer"],
"edge_attr_names":
["EDGE_ID","START_NODE_ID","END_NODE_ID","NEXT_LEFT_EDGE_ID","PREV_LEFT_EDGE_ID","NEX
T_RIGHT_EDGE_ID","PREV_RIGHT_EDGE_ID","LEFT_FACE_ID","RIGHT_FACE_ID"],
"edge_attr_types":
["integer","integer","integer","integer","integer","integer","integer","integer","int
eger"],
"node_attr_names":["NODE_ID","EDGE_ID","FACE_ID"],
"node_attr_types":["integer","integer","integer"],
"primitives":[
{"type":"Face", "properties":{"FACE_ID":"-1", "BOUNDARY_EDGE_ID":"0",
"ISLAND_EDGE_ID_LIST":[-1,-2,4,6]}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":[25,30,25,35]},
"properties":{"EDGE_ID":"3", "START_NODE_ID":"2", "END_NODE_ID":"3",
"NEXT_LEFT_EDGE_ID":"-3", "PREV_LEFT_EDGE_ID":"2", "NEXT_RIGHT_EDGE_ID":"2",
"PREV_RIGHT_EDGE_ID":"3", "LEFT_FACE_ID":"2", "RIGHT_FACE_ID":"2"}},
{"type":"Edge", "geometry":{"type":"LineString", "coordinates":
[36,38,38,35,41,34,42,33,45,32,47,28,50,28,52,32,57,33]}, "properties":
{"EDGE_ID":"4", "START_NODE_ID":"5", "END_NODE_ID":"6", "NEXT_LEFT_EDGE_ID":"-5",
"PREV_LEFT_EDGE_ID":"-4", "NEXT_RIGHT_EDGE_ID":"4", "PREV_RIGHT_EDGE_ID":"5",
"LEFT_FACE_ID":"-1", "RIGHT_FACE_ID":"-1"}},
{"type":"Node", "geometry":{"type":"Point", "coordinates":[36, 38]}, "properties":
{"NODE_ID":"5", "EDGE_ID":"4", "FACE_ID":"0"}}
]}
3.1.3 Interpreting Data Returned from the Map Data Server
The map data server returns data in a compressed GeoJSON format. Some minor
changes and additions to the standard GeoJSON are made to improve performance
and the usefulness of the information.
The following is a sample response:
{"type":"FeatureCollection",
"collectionName":"theme1",
"srs":3857,
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"geodetic":false,
"bbox":[-17566686.86258, 2414218.89842, -7905675.57465, 8629389.76988],
"attr_names":["CITY","STATE_ABRV","POP90","RANK90"],
"attr_types":["string","string","double","double"],
"features":[
{"type":"Feature","_id":"AAASQ3AAEAAAAMbAAA","geometry": {"type":"Point",
"coordinates":[-119.99823, 38.9052]},"properties":{"CITY":"SOUTH LAKE TAHOE",
"SALES":"125.8", "NAME":"FACTORY STORES AT THE Y", "_label_":"FACTORY STORES AT THE
Y"},"styles":{"rendering":{"style":"M.SMALL CIRCLE"},"labeling":{"style":"T.RED
STREET", "columns":["_label_"]}}},
{"type":"Feature","_id":"AAASQ3AAEAAAAMbAAB","geometry": {"type":"Point",
"coordinates":[-121.95073, 37.53356]},"properties":{"CITY":"FREMONT",
"SALES":"186.8", "NAME":"OHLONE VILLAGE", "_label_":"OHLONE VILLAGE"},"styles":
{"rendering":{"style":"M.SMALL CIRCLE"},"labeling":{"style":"T.RED STREET",
"columns":["_label_"]}}},
{"type":"Feature","_id":"AAASQ3AAEAAAAMbAAC","geometry": {"type":"Point",
"coordinates":[-118.48844, 34.02353]},"properties":{"CITY":"SANTA MONICA",
"SALES":"9.1", "NAME":"SANTA MONICA PLACE", "_label_":"SANTA MONICA PLACE"},"styles":
{"rendering":{"style":"M.SMALL CIRCLE"},"labeling":{"style":"T.RED STREET",
"columns":["_label_"]}}},
{"type":"Feature","_id":"AAASQ3AAEAAAAMbAAD","geometry": {"type":"Point",
"coordinates":[-118.55093, 34.42104]},"properties":{"CITY":"SANTA CLARITA",
"SALES":"52.6", "NAME":"VALENCIA TOWN CENTER", "_label_":"VALENCIA TOWN
CENTER"},"styles":{"rendering":{"style":"M.SMALL CIRCLE"},"labeling":{"style":"T.RED
STREET", "columns":["_label_"]}}},
{"type":"Feature","_id":"AAASQ3AAEAAAAMbAAE","geometry": {"type":"Point",
"coordinates":[-122.56007, 38.08187]},"properties":{"CITY":"NOVATO",
"SALES":"119.1", "NAME":"VINTAGE OAKS AT NOVATO", "_label_":"VINTAGE OAKS AT
NOVATO"},"styles":{"rendering":{"style":"M.SMALL CIRCLE"},"labeling":{"style":"T.RED
STREET", "columns":["_label_"]}}}]}
The response contains a minimal header plus an array of features. The header
includes the spatial reference system (srs) ID and the minimum bounding box of the
result data. The array of features includes attribute names and their types. Possible
type names include:
"byte","short","int","long","float","double","char","string","boolean", "date"
For each feature, the following fields apply:
•
type: Always Feature.
•
_id: Optional ID or key attribute.
•
geometry: The actual geometry encoded in the modified GeoJSON format.
•
properties: An object containing all the properties (name-value pairs) for the
feature.
•
styles: An optional styling information object. Contains two embedded objects,
rendering and labeling, which share the same structure: basically an object
containing a style field and an optional columns array. Currently only predefined
themes support including styling information in the response; a dynamic theme's
response contains no styling information.
•
label_box: A 4-element array specifying the minX, minY, maxX, and maxY of the label
box. Only a polygon can have a label box.
Note that the labeling text is always included as a pseudo-property with the name
_label_ in the property list.
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3.1.4 Map Data Server Error Handling
If the map data server cannot process a data request, it will send a JSON response
containing an error object. This JSON error object may look like the following:
{"error":
{"code": "ora-500",
"message": "Table requested does not exist",
"details": "maybe a stack trace here..."
}
}
In the preceding JSON object, code is the error code known only to the map data
serve, message contains a short message that can be displayed to the end user in a
warning dialog, and details is an optional field that may contain more details (such as
the stack trace if included).
3.2 Map Tile Server
The map tile server is a map image caching engine that fetches, caches, and serves
pregenerated, fixed-size map image tiles.
It is implemented as a Java servlet that is part of the map visualizer server. The map
tile server accepts requests that ask for map image tiles specified by tile zoom level
and tile location (mesh code), and it sends the requested tiles back to clients.
Figure 3-1 shows the basic workflow of the map tile server.
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Figure 3-1
Workflow of the Map Tile Server
As shown in Figure 3-1, when the map tile server receives a request for a map tile, it
searches for the tile in the cache storage system. If the tile is cached, the map tile
server sends the tile to the client. If the tile is not cached, the map tile server fetches
the tile, saves it in the cache, and sends it to the client.
You can use the map visualizer administration tool to manage the map tile server.
•
Map Tile Server Concepts
•
Map Tile Server Configuration
•
Map Cache Auto-Update
•
UTFGrid for Map Tiles: Including Text Information About Features
•
External Map Source Adapter
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3.2.1 Map Tile Server Concepts
This section explains map tile server concepts that you need to know to be able to use
Oracle Maps effectively.
•
Map Tile Layers and Map Tile Sources
•
Storage of Map Image Tiles
•
Coordinate System for Map Tiles
•
Tile Mesh Codes
•
Map Tile Requests
•
Tiling Rules
•
Tile Background Color and Out-of-Bounds Color
3.2.1.1 Map Tile Layers and Map Tile Sources
All map tile layers are managed by the map tile server. The map tile server fetches
and stores the map image tiles that belong to the map tile layer and returns map
image tiles to the client. The map tile server can manage multiple map tile layers.
Each map tile layer can have multiple predefined zoom levels. Each zoom level is
assigned a zoom level number ranging from 0 to n-1, where n is the total number of
zoom levels. Zoom level 0 is the most zoomed out level and zoom level n-1 is the most
zoomed in level.
The map is evenly divided into same-sized small map image tiles on each zoom level.
Clients specify a map tile by its zoom level and tile mesh code.
A map tile layer can come from two different types of sources:
•
Internal map visualizer base maps rendered by the map visualizer map rendering
engine. A map visualizer base map consists of a set of predefined themes and
must be predefined in the database view USER_SDO_MAPS.
•
Maps rendered by an external web map services providers. An external web map
services provider is a server that renders and serves maps upon client requests
over the web. If you properly configure an adapter that can fetch maps from the
external map services provider, the map tile server can fetch and cache map tiles
generated by the external map services provider. (A map visualizer instance other
than the map visualizer inside which the map tile server is running is also
considered an external map services provider.)
3.2.1.2 Storage of Map Image Tiles
Oracle Maps has three options for handling the storage of map image tiles:
•
Store the tiles using the local file system .
If you use the local file system for caching, you can customize the path that is
used for this storage as part of the map tile server configuration settings.
•
Store the tiles in a database table .
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If you use a database table for caching, you must create the database table, and
set the TILES_TABLE column to that table for the tile layer in the
USER_SDO_CACHED_MAPS view.
•
Stream the tiles directly without storing them .
If you do not want to cache any image tiles, you must indicate that in the tile layer's
definition.
•
Store the tiles using the local file system
•
Store the tiles in a database table
•
Stream the tiles directly without storing them
3.2.1.2.1 Store the tiles using the local file system
In a file system, each tile layer has its own storage root directory, which is specified by
the <cache_storage> element's root_path attribute in the tile layer definition. If that
attribute is not specified, then the default storage location specified in the
mapViewerConfig.xml file <tile_storage> element is used as the root path. For example,
if the root path is defined as /scratch/tilecache/, and a data source named MVDEMO
has a tile layer named DEMO_MAP with 19 zoom levels, after the server is
instantiated the folder /scratch/tilecache/MVDEMO.DEMO_MAP is created, and it contains
19 subfolders (/0, /1, …, /18), each for storing the image tiles in that zoom level.
Under each zoom level, there are two options to organize its subfolders for map tiles.
One is the default option, which uses a mesh code tree structure; the other, called xyz
storage scheme, uses the tile's row and column values as subfolder and tile name to
store the map tile. Both storage options start from the tile's mesh code value for each
zoom level (see Tile Mesh Codes for details about the tile mesh code). Each tile in a
zoom level can be represented using its mesh code value pair (mx, my), where the mx
and my are integer values in the horizontal and vertical directions respectively. The tile
at the lower left corner has a value of (0, 0). A tile can also be located using its tile row
and tile column value pair (tile_column, tile_row). A tile at the upper left corner has a
value of (0, 0).
3.2.1.2.2 Store the tiles in a database table
Image tiles can be stored in a database table, as follows.
1.
Create a table for storing the image tiles. For example:
CREATE TABLE tile_dbt (
tile_layer varchar2(64),
zoom_level number,
x number,
y number,
modified TIMESTAMP,
data BLOB);
COMMIT;
2.
Update the TILES_TABLE column in USER_SDO_CACHED_MAPS view for the
tile layer. For example, if you have a tile layer DEMP_MAP and you want to use
the table created in step 1 to store its map tiles, then update the tile layer's
TILES_TABLE column as follows:
UPDATE user_sdo_cached_maps SET tiles_table='tiles_dbt' WHERE name='DEMP_MAP';
3.
Restart the map visualizer server to make the changes take effect.
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Using this example, the map image tiles for tile layer DEMP_MAP will be stored in the
database table TILE_DBT.
3.2.1.2.3 Stream the tiles directly without storing them
If the tile contents may change constantly (such as a real-time cloud cover satellite
image map) or if you do not want to store the image tiles, you can stream the tiles
directly without storing them.
To choose this option, set the persistent_tiles attribute to false in the
<map_tile_layer> element in the tile layer's definition. (The default value for the
persistent_tiles attribute is true.). Example 3-1 inserts a tile layer named
DEMO_MAP, with the persistent_tiles attribute sets to false so that no map image
tiles will be cached for this tile layer.
Example 3-1
Streaming Tiles Without Storing Them
INSERT INTO user_sdo_cached_maps values(
'DEMO_MAP',
'an example tile layer that does not cache image tiles',
'',
'YES',
'YES',
'<map_tile_layer name="DEMO_MAP_TREEMESH" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3" persistent_tiles="false">
<internal_map_source data_source="mvdemo" base_map="DEMO_MAP" bgcolor="#dddddd"
out_of_bounds_color="#eeddff"/>
<tile_storage root_path="/temp" short_path="false" />
<coordinate_system srid="8307" minX="-180.0" maxX="180.0" minY="-90.0" maxY="90.0"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="2132.729583849784" max_scale="559082264.0287178"/>
</map_tile_layer>',
'DEMO_MAP',
'');
COMMIT;
3.2.1.3 Coordinate System for Map Tiles
Map images are cached and managed by the map tile server as small same-size
rectangular image tiles. Currently we support tiling on any two-dimensional Cartesian
coordinate system. A geodetic coordinate system can also be supported when it is
mapped as if it is a Cartesian coordinate system, where longitude and latitude are
treated simply as two perpendicular axes, as shown in Figure 3-2.
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Figure 3-2
Tiling with a Longitude/Latitude Coordinate System
On each zoom level, the map tiles are created by equally dividing the whole map
coordinate system along the two dimensions (X and Y, which inFigure 3-2 represent
latitude and longitude). The map tile server needs this dimensional information of the
map coordinate system in order to create map image tiles, and therefore you must
include this information in the map tile layer configuration settings.
The whole map coordinate system can be represented by a rectangle, and its
boundary is specified by (Xmin, Ymin) and (Xmax, Ymax), where Xmin is the minimum
X value allowed in the coordinate system, Ymin is the minimum Y value allowed, Xmax
is the maximum X value allowed and Ymax is the maximum Y value allowed. In
Figure 3-2, Xmin is –180, Ymin is –90, Xmax is 180, and Ymax is 90.
You must also specify the spatial referencing ID (SRID) of the coordinate system to
enable the map tile server to calculate map scales.
3.2.1.4 Tile Mesh Codes
Each map tile is specified by a mesh code, which is defined as a pair of integers (Mx,
My), where Mx specifies the X dimension index of the tile and My specifies the Y
dimension index of the tile. If the tile is the ith tile on X dimension starting from Xmin,
then Mx should be i-1. If the tile is the jth tile on Y dimension starting from Ymin, then
My should be j-1. Figure 3-3 shows the mesh codes of the tiles on a map.
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Figure 3-3
Tile Mesh Codes
The JavaScript map client automatically calculates which tiles it needs for displaying
the map in the web browser, and it sends requests with the mesh codes to the server.
Mesh codes are transparent to the application, and application developers do not need
to deal with mesh codes directly.
3.2.1.5 Map Tile Requests
The map tile server handles map tile requests. A map tile request can be in key/value
pair format or REST format:
•
Map tile request in key/value pair format
For example, if data source DS_NAME has a tile layer TL_NAME, then to get a
map tile image in PNG format from zoom level 2 and mesh code (3.2), the URL
may be formatted as:
http://localhost:8080/mapviewer/mcserver?
request=gettile&format=PNG&zoomlevel=2&mapcache=DS_NAME.TL_NAME&mx=3&my=2
•
Map tile request in REST format
A general format of a request in REST format is:
http://localhost:8080/mapviewer/mcserver/DS_NAME/TL_NAME/{zoom}/{row}/
{column}.png
For example, to send the same map tile request shown in the preceding key/value
pair example but in a REST format, the URL may be:
http://localhost:8080/mapviewer/mcserver/DS_NAME/TL_NAME/2/1/3.png
The mesh code in the key/value pair format has an origin of the lower-left corner, but
the REST format requests a tile's row and column, and thus the origin is at the upper-
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left corner. Because the two formats have different origins, the my value is different
from the row value, but the mx value is the same as the column value.
Normally, map tile requests are encapsulated in the map visualizer JavaScript API
libraries, so the API handles map tile requests. However, if you are using a third
party's JavaScript API to communicate with the map visualizer server, you may need
to specify the map tile request format in your application. For example, if you use the
Leaflet JavaScript API to get map tiles from a map visualizer server, you may need to
set the URL template for its L.tileLayer as:
http://localhost:8080/mapviewer/mcserver/DS_NAME/TL_NAME/{z}/{y}/{x}.png.
3.2.1.6 Tiling Rules
You must create tiling rules that determine how the map is divided and how tiles are
created. The map tile server uses these tiling rules to divide the map into small map
image tiles that are stored in the tile storage system. These rules are also used by the
JavaScript map client.
Because all tiles on a given zoom level are the same size, the map tile server needs to
know the following information to perform the tile division:
•
The map tile image size (width and height), specified in screen pixels. This is the
physical size of the tile images.
•
The tile size specified according to the map coordinate system. For example, if the
map uses a geodetic coordinate system, the tile width and height should be
defined in degrees. The size can be specified either explicitly by tile width and
height or implicitly by map scale. (Map scale, combined with tile image size, can
be used to derive the tile width and height according to the map coordinate
system.)
The preceding information constitutes the tiling rule for a given zoom level. Each zoom
level must have its own tiling rule. You must define the tiling rules when you specify
the configuration settings for the map tile server, as described in Map Tile Server
Configuration.
3.2.1.7 Tile Background Color and Out-of-Bounds Color
Two attributes in a tile layer metadata definition which affect a tile's color: bgcolor
(background color) and out_of_bounds_color (out-of-bounds color). The bgcolor
attribute value is used for filling areas within the valid data area of a tile layer (the valid
data area is defined by minX, minY, maxY, maxY), while the out_of_bounds_color
attribute value is used for filling areas that are outside the valid data area. Both
attributes have the same default values (Color(192, 192, 192)).
If a tile-fetching process failed due to an exception on the attempt to generate a tile,
then the tile filled with out-of-bounds color is used as its substitute, regardless of
whether it is within the valid data area. However, such a substitute tile due to tilefetching exception is not permanently stored on disk; rather, it is streamed to the client
on a temporary basis. The map visualizer will retry the tile generation on subsequent
requests, if the temporary tile data in the client browser's cache is purged or if a
different client initiates the request.
If bgcolor is set to none, then the tile becomes transparent; that is, the background
color of the HTML page replaces the attribute values for both bgcolor and
out_of_bounds_color.
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3.2.2 Map Tile Server Configuration
Map tile server configuration settings are stored in local configuration files and in
database views. You can customize these settings.
•
Global Map Tile Server Configuration
•
Map Tile Layer Configuration
•
Map Tile Storage Schemes: Internal Mesh Code or XYZ
•
Creating a Map Tile Layer Using an External Web Map Source
3.2.2.1 Global Map Tile Server Configuration
Global map tile server settings, such as logging options and the default cache storage
directory, are stored in the map visualizer configuration file mapViewerConfig.xml, which
is under the directory $MAPVIEWER_HOME/web/WEB-INF/conf.
The map tile server configuration settings are defined in element <map_tile_server>
inside the top-level <mapperConfig> element, as shown in the following example:
<map_tile_server>
<tile_storage default_root_path="/scratch/tilecache/"/>
</map_tile_server>
The <tile_storage> element specifies the map tiles storage settings. The
default_root_path attribute specifies the default file system directory under which the
cached tile images are to be stored. If the default root directory is not set or not valid,
the default root directory is $MAPVIEWER_HOME/web/tilecache. A subdirectory under this
directory will be created and used for a map tile layer if the map tile layer configuration
does not specify the map tiles storage directory for itself. The name of the subdirectory
will be the same as the name of the map tile layer.
3.2.2.2 Map Tile Layer Configuration
The configuration settings for a map tile layer are stored in the
USER_SDO_CACHED_MAPS metadata view, which is described in
xxx_SDO_CACHED_MAPS Views. You should normally not manipulate this view
directly, but should instead use the map visualizer administration tool, which uses this
view to configure map tile layers.
Each database user (schema) has its own USER_SDO_CACHED_MAPS view. Each
entry in this view stores the configuration settings for one map tile layer. If the map tile
layer is based on an internal map visualizer base map or themes, the base map or
themes associated with the map tile layer must be defined in the same database
schema where the map tile layer configuration settings are stored.
The map tile server obtains the map source configuration by querying the
USER_SDO_CACHED_MAPS view using the database connections specified by the
map visualizer data sources. This happens when the map tile server is started or a
new data source is added to the map visualizer as the result of a map visualizer
administration request.
For the DEFINITION column in the USER_SDO_CACHED_MAPS view, the map
source definition has the following general format:
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<map_tile_layer
name = "map tile layer name"
image_format ="tile-image-format">
<internal_map_source
data_source="name-of-data-source"
base_map="name-of-MapViewer-base-map"
bgcolor="base-map-background-color"
antialias="whether-to-turn-on-antialiasing"
/>
</internal_map_source>
<external_map_source
url="external-map-service-url"
adapter_class="name-of-adapter-class"
proxy_host=" proxy-server-host "
proxy_port="proxy-server-port"
timeout="request-timeout"
request_method="http-request-method: 'GET'|'POST'">
<properties>
<property name="property-name" value="property-value"/>
…
</properties>
</external_map_source>
<tile_storage
root_path="disk-path-of-cache-root-directory"
</tile_storage>
<coordinate_system
srid="coordinate-system-srid"
minX="minimum-allowed-X-value"
maxX="maximum-allowed-X-value"
minY="minimum-allowed-Y-value"
maxY="maximum-allowed-Y-value">
</coordinate_system>
<tile_image
width="tile-image-width-in-screen-pixels"
height="tile-image-height-in-screen-pixels" >
</tile_image>
<tile_bound>
<coordinates> … </coordinates>
</tile_bound>
<zoom_levels
levels="number-of-zoom-levels"
min_scale="map-scale-at-highest-zoom-level"
max_scale="map-scale-at-lowest-zoom-level"
min_tile_width="tile-width-specified-in-map-data-units-athighest-zoom-level"
max_tile_width="tile-width-specified-in-map-data-units-atlowest-zoom-level">
<zoom_level
description="zoom-level-description"
level_name="zoom-level-name"
scale="map-scale-of-zoom-level"
tile_width ="tile-width-specified-in-map-data-units"
tile_height ="tile-height-specified-in-map-data-units">
<tile_bound>
<coordinates> … </coordinates>
</tile_bound>
</zoom_level>
…
</zoom_levels>
</map_tile_layer>
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The DTD of the map tile layer definition XML is listed in Map Tile Layers.
Example 3-2 shows the XML definition of an internal map tile layer that is based on a
base map; Example 3-3 shows the XML definition of an internal map tile layer that is
based on themes (not on a base map); and Example 3-4 shows the XML definition of
an external map tile layer. Explanations of the <map_tile_layer> element and its
subelements follow these examples.
Example 3-2
XML Definition of an Internal Map Tile Layer Based on a Base Map
<?xml version = '1.0'?>
<!-- XML definition of an internal map tile layer.
-->
<map_tile_layer image_format="PNG">
<internal_map_source base_map="demo_map"/>
<tile_storage root_path="/scratch/mapcache/"/>
<coordinate_system
srid="8307"
minX="-180" maxX="180"
minY="-90" maxY="90"/>
<tile_image width="250" height="250"/>
<zoom_levels>
<zoom_level description="continent level" scale="10000000"/>
<zoom_level description="country level" scale="3000000"/>
<zoom_level description="state level" scale="1000000"/>
<zoom_level description="county level" scale="300000"/>
<zoom_level description="city level" scale="100000"/>
<zoom_level description="street level" scale="30000"/>
<zoom_level description="local street level" scale="10000"/>
</zoom_levels>
</map_tile_layer>
Example 3-3
XML Definition of an Internal Map Tile Layer Based on Themes
<?xml version = '1.0' encoding = 'UTF-8'?>
<map_tile_layer name="TL1" image_format="PNG" http_header_expires="168.0"
utfgrid="true" utfgrid_resolution="4" concurrent_fetching_threads="3">
<internal_map_source data_source="MVDEMO" bgcolor="none"
out_of_bounds_color="#ffffff" base_map="" db_tile_table=""/>
<tile_storage root_path="/temp" xyz_storage_scheme="true"/>
<coordinate_system srid="3857" minX="-2.0037508E7" minY="-2.0037508E7"
maxX="2.0037508E7" maxY="2.0037508E7"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.714"/>
<tile_meters_per_unit value="1.0"/>
<zoom_levels levels="19" min_scale="2132.72958384" max_scale="5.59082264028E8"
min_tile_width="152.874538064" max_tile_width="4.00751429065E7">
<zoom_level level="0" name="level0" tile_width="4.00751429065E7"
tile_height="4.00751429065E7"/>
<zoom_level level="1" name="level1" tile_width="2.003757145325E7"
tile_height="2.003757145325E7"/>
<zoom_level level="2" name="level2" tile_width="1.0018785726625258E7"
tile_height="1.001878572662E7"/>
<zoom_level level="3" name="level3" tile_width="5009392.86331"
tile_height="5009392.86331"/>
<zoom_level level="4" name="level4" tile_width="2504696.431656"
tile_height="2504696.431656"/>
<zoom_level level="5" name="level5" tile_width="1252348.215828"
tile_height="1252348.215828"/>
<zoom_level level="6" name="level6" tile_width="626174.1079140786"
tile_height="626174.107914"/>
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<zoom_level level="7" name="level7" tile_width="313087.0539570393"
tile_height="313087.053957"/>
<zoom_level level="8" name="level8" tile_width="156543.5269785"
tile_height="156543.5269785"/>
<zoom_level level="9" name="level9" tile_width="78271.763489"
tile_height="78271.763489"/>
<zoom_level level="10" name="level10" tile_width="39135.8817446"
tile_height="39135.8817446"/>
<zoom_level level="11" name="level11" tile_width="19567.9408723"
tile_height="19567.9408723"/>
<zoom_level level="12" name="level12" tile_width="9783.9704361"
tile_height="9783.9704361"/>
<zoom_level level="13" name="level13" tile_width="4891.9852180"
tile_height="4891.9852180"/>
<zoom_level level="14" name="level14" tile_width="2445.9926090"
tile_height="2445.99260903"/>
<zoom_level level="15" name="level15" tile_width="1222.99630451"
tile_height="1222.99630451"/>
<zoom_level level="16" name="level16" tile_width="611.49815225"
tile_height="611.49815225"/>
<zoom_level level="17" name="level17" tile_width="305.74907612"
tile_height="305.74907612"/>
<zoom_level level="18" name="level18" tile_width="152.87453806"
tile_height="152.87453806"/>
</zoom_levels>
<auto_update finest_level_to_refresh="13" dirty_mbr_batch="100"
dirty_mbr_cap="1000">
<dirty_mbr_table name="TL1MBR"/>
<logtable name="TL1LOG"/>
</auto_update>
<themes>
<theme name="UTFGRID_THEME_DEMO_STATES" from_level="0" to_level="18"/>
<theme name="UTFGRID_THEME_DEMO_COUNTIES" from_level="0" to_level="18"/>
<theme name="UTFGRID_THEME_DEMO_HIGHWAYS" from_level="0" to_level="18"/>
<theme name="UTFGRID_THEME_DEMO_CITIES" from_level="0" to_level="18"/>
</themes>
</map_tile_layer>
Example 3-4
XML Definition of an External Map Tile Layer
<?xml version = '1.0'?>
<!-- XML definition of an external map tile layer.-->
<map_tile_layer name="TILELAYER1" image_format="PNG">
<external_map_source
url="http://mycorp.com:7001/mapviewer/wms/"
request_method="GET"
adapter_class="oracle.lbs.mapcache.adapter.WMSAdapter"
adapter_class_path="">
<properties>
<property name="datasource" value="mvdemo"/>
<property name="version" value="1.1.1"/>
<property name="srs" value="EPSG:4326"/>
<property name="layers" value="THEME_DEMO_COUNTIES,THEME_DEMO_HIGHWAYS"/>
<property name="format" value="image/png"/>
<property name="transparent" value="true"/>
</properties>
</external_map_source>
<tile_storage root_path="/scratch/tmp/"/>
<coordinate_system srid="8307" minX="-180.0" minY="-90.0" maxX="180.0"
maxY="90.0"/>
<tile_image width="256" height="256"/>
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<!—
The following <zoom_levels> element does not have any
<zoom_level> element inside it. But since it has its levels,
min_scale and max_scale attributes set, map tile server will
automatically generate the <zoom_level> elements for the 10
zoom levels.
-->
<zoom_levels levels="10" min_scale="1000.0" max_scale="2.5E8">
</zoom_levels>
</map_tile_layer>
The top-level element is <map_tile_layer>. The image_format attribute specifies the tile
image format; the currently supported values for this attribute are PNG, GIF, and JPG.
PNG and GIF images are generally better for vector base maps, while JPG images are
generally better for raster maps, such as satellite imagery, because of a better
compression ratio. Currently, only tile images in PNG format can have transparent
background.
•
The http_header_expires attribute specifies the number of hours after which a
cached tile layer can be considered stale.
•
The utfgrid attribute, when set to true, indicates that a companion UTFGrid
dataset for an image file will be generated. (The default value is false.)
•
The utfgrid_resolution attribute specifies how fine the grid data is compared to
the image tile. For example, a value of 4 (the default) indicates that one grid cell
represents 4 by 4 pixels in its companion image tile.
•
The concurrent_fetching_threads attribute defines the maximum number of
concurrent tile fetching threads that may be created for fetching image tiles for this
tile layer. (The default value is 3.)
•
The fetch_larger_tile attribute , when true (the default), tells the tile server that if
the tile is not available in the cache, the tile's adjacent tiles will also be generated.
This parameter does bot affect the getTile performance when the requested tiles
are already available in the cache. The default setting (true) is intended to improve
server response time.
•
The persistent_tiles attribute, when true (the default), specifies that image tiles
will be saved is the server's disk cache. If this attribute is set to false, then each
getTile request invokes an image tile rendering process in the map visualizer
server, and the newly acquired image tile is not cached for future use. Cases
where you may want to specify false include (A) a GeoRaster theme is used by a
tile layer and you do not want duplicate raster images in the map visualizer's disk
cache, or (B) you want the tile server always to provide up-to-date image tiles.
The <internal_map_source> element is required only if the map tiles are rendered by the
local map visualizer instance.
•
The base_map attribute is required and specifies the predefined map visualizer base
map that is cached by the map tile server; its value should match an entry in the
BASE_MAP column in the USER_SDO_CACHED_MAPS view.
•
The bgcolor attribute is optional and specifies the background color of the map. If
the value of this attribute is set to NONE, the background will be transparent.
(Currently, only tile images in PNG format can have a transparent background.)
•
The out_of_bounds_color attribute is optional and specifies the color for areas that
are outside the data boundaries. The data boundaries are specified by the
attributes of the <coordinate_system> element.
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•
The db_tile_table attribute is optional, specifies the database table in which to
cache the tile layer's image tiles. If the attribute is not specified, the tiles are
cached in the map visualizer's disk cache.
The <external_map_source> element is required only if the map tiles are rendered by an
external map services provider. This element has the following attributes:
•
The url attribute is required and specifies the map service URL from which the
map tiles can be fetched (for example, http://myhost/mapviewer/omserver).
•
The adapter_class attribute is required and specifies the full name of the map
adapter class, including the package names (for example, mcsadapter.MVAdapter).
•
The proxy_host and proxy_port attributes are needed only if the external map
provider server must be accessed through a proxy server; these attributes specify
the host name and port number, respectively, of the proxy server. If proxy_host is
specified as NONE, all map tile requests will be sent directly to the remote server
without going through any proxy server. If proxy_host is omitted or specifies an
empty string, the global map visualizer proxy setting defined in the
mapViewerConfig.xml file will be used when map tile requests are sent.
•
The timeout attribute is optional and specifies the number of milliseconds for which
the map tile server must wait for an external map tile image before giving up the
attempt. The default timeout value is 15000.
•
The request_method attribute is optional and the HTTP request method for sending
map tile requests; its value can be POST (the default) or GET.
For more information about external map tile layers and an example, see Creating a
Map Tile Layer Using an External Web Map Source.
The <properties> element in the <external_map_source> element can include multiple
<property> elements, each of which specifies a user-defined parameter for use by the
map adapter when it fetches map tiles. The same map source adapter can use
different set of parameters to fetch different map tile layers. For example, the sample
map visualizer adapter mcsadapter.MVAdapter shipped with the map visualizer accepts
parameters defined as follows:
<properties>
<property name="data_source" value="elocation"/>
<property name="base_map" value="us_base_map"/>
</properties>
However, by changing the value attribute values, you can use this adapter to fetch a
different base map from the same data source or a different data source.
The <tile_storage> element specifies storage settings for the map tile layer.
•
The optional root_path attribute specifies the file system directory to be used as
the root directory of the tile storage. If this attribute is omitted or invalid, the default
root directory defined in the mapViewerConfig.xml file is used.
•
The optional xyz_storage_scheme element controls how the directory structure of
map tiles in the disk cache is organized. The default value (false) causes the map
visualizer internal mesh code storage scheme to be used. The value true causes
the XYZ storage scheme to be used. For more information, see Map Tile Storage
Schemes: Internal Mesh Code or XYZ
The <coordinate_system> element specifies the map coordinate system, and it has
several required attributes. The srid attribute specifies the spatial reference ID of the
coordinate system. The minX attribute specifies the lower bound of the X dimension;
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the minY attribute specifies the lower bound of the Y dimension; the maxX attribute
specifies the upper bound of the X dimension; and the maxY attribute specifies the
upper bound of the Y dimension. For the standard longitude/latitude (WGS 84)
coordinate system, the srid value is 8307; and the minX, minY, maxX, and maxY values
are -180, -90, 180, and 90, respectively.
For an internal map tile layer, the map coordinate system can be different from the
data coordinate system. If the two are different, the map tile server transforms the map
data into the coordinate system defined in the <coordinate_system> element and
renders map tile images using this coordinate system.
The <tile_image> element specifies the tile image size settings, and it has the following
required attributes: width specifies the width of the tile images in screen pixels, and
height specifies the height of the tile images in screen pixels.
The optional <tile_bound> element specifies the bounding box of the cached map tiles.
The map tile server only fetches tiles inside this box, and returns a blank tile if the
requested tile is outside this box. The bounding box is specified by a rectangle in the
map data coordinate system. The rectangle is specified by a <coordinates> element in
the following format:
<coordinates>minX, minY, maxX, maxY</coordinates>
The default cache bounding box is the same bounding box specified in the
<coordinate_system> element.
The optional <tile_dpi> element specifies the map display screen resolution as a "dots
per inch" value. If this element is not specified, the value specified in the
mapViewerConfig.xml file will be assigned to the tile layer. If the map visualizer must
comply with OGC standards in exposing the tile layer in its WMTS service, then you
must specify this element with the following value: 90.714
The optional <tile_meters_per_unit> element specifies the meters per unit. The unit is
defined indirectly by the srid attribute in the <coordinate_system> element. For
example, if the srid is 3857, its unit is meters, and thus the value for this attribute must
be 1.0; or if the srid is 8307, its unit is decimal degrees, and thus the value may be set
to 111319.49. If this element is not specified, a map visualizer internal process
calculates the value according to the data bounds, and the result is very close to
111319.49. If this tile layer is to be exposed by the map visualizer to provide WMTS
services, and if srid is 8307, then you must set this element's value to 111319.49 to
comply with OGC standards.
The <zoom_levels> element specifies the predefined zoom levels. Only image tiles at
predefined zoom levels will be cached and served by the map tile server. The
<zoom_levels> element can have multiple <zoom_level> elements, each of which
specifies one predefined zoom level. If there are no <zoom_level> elements, the map
tile server automatically generates the <zoom_level> elements by using the following
attributes inside the <zoom_levels> element. (These attributes can be omitted and will
be ignored if any <zoom_level> elements exist.)
•
levels specifies the total number of zoom levels.
•
min_scale specifies the scale of map images at the highest (zoomed in the most)
zoom level.
•
max_scale specifies the scale of map images at the lowest (zoomed out the most)
zoom level.
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•
min_tile_width specifies the width of map tiles at the highest zoom level. The width
is specified in map data units.
•
max_tile_width specifies the width of the map tiles at the lowest zoom level. The
width is specified in map data units.
For the map tile server to be able to generate the definitions of individual zoom levels
automatically, you must specify either of the following combinations of the preceding
attributes:
•
levels, min_scale, and max_scale
•
levels, min_tile_width, and max_tile_width
When the zoom levels are defined this way, the map tile server automatically derives
the definition of all the individual zoom levels and updates the XML definition with the
<zoom_level> elements generated for the zoom levels. You can then make adjustments
to each zoom level if you want.
Each zoom level is assigned a zoom level number by the map tile server based on the
order in which the zoom levels are defined. The first zoom level defined in the
<zoom_levels> element is zoom level 0, the second zoom level is zoom level 1, and so
on. These zoom level numbers are used in the tile requests to refer to the predefined
zoom levels.
The <zoom_level> element specifies a predefined zoom level, and it has several
attributes. The description attribute is optional and specifies the text description of the
zoom level. The level_name attribute is optional and specifies the name of the zoom
level. The scale attribute specifies the map scale of the zoom level; it is required if the
attributes tile_width and tile_height are not defined. The tile_width and tile_height
attributes specify the tile width and height, respectively, in map data units. The
fetch_larger_tiles attribute is optional and specifies whether to fetch larger map
images instead of the small map image tiles; a value of TRUE (the default) means that
larger map images that may consist multiple map tiles will be fetched and broken into
small map image tiles, which might save network round trips between the map tile
server and the map services provider.
In the <zoom_level> element, you must specify either the scale attribute or both the
tile_width and tile_height elements.
The <tile_bound> element within the <zoom_level> element optionally specifies the
bounding box of the cached map tiles for the zoom level. The map tile server only
fetches tiles inside this box, and returns a blank tile if the requested tile is outside this
box. The bounding box is specified by a rectangle specified in map data coordinate
system. The rectangle is specified by a <coordinates> element (explained earlier in this
topic) If you specify the <tile_bound> element within the <zoom_level> element, it
overrides the overall cache bounding box settings specified by the <tile_bound>
element that is above it in the XML hierarchy.
The <auto_update> element defines how the tile layer's disk cache is to be
automatically updated when spatial data in the base table is modified, For details, see
Add the <auto_update> element to tile layer definition.
The <themes> element defines a layer based on themes (as opposed to a layer based
on a base map). The themes to be used to render image tiles are listed in its
subelements. In each subelement <theme>, the name attribute is required to specify a
predefined theme in the metadata. The other two optional attributes, from_level and
to_level, define the visibility of the that theme. The default values for those two
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attributes are from_level of 0 (which contains the least map detail) and to_level of the
last level (which contains the most map detail).
3.2.2.3 Map Tile Storage Schemes: Internal Mesh Code or XYZ
The xyz_storage_scheme attribute of the <file_storage> element (described in Map Tile
Layer Configuration) controls how the directory structure of map tiles in the disk cache
is organized. The default scheme uses the map visualizer's internal mesh codes, but
you can instead choose the XYZ storage scheme.
Figure Figure 3-4 shows both storage schemes.
Figure 3-4
Internal Mesh Code and XYZ Map Tile Storage Schemes
The details of the map visualizer internal mesh code are nor important for users. You
need only know that there are two different storage scheme options, and that the XYZ
storage scheme is analogous to the scheme used by several map data providers.
Therefore, if you want to export tiles from some zoom levels for an offline project (local
tile layer), if you find the XYZ storage scheme more intuitive, you can specify it.
In the map visualizer XYZ storage scheme, the naming of subdirectories is in the
form /z/y/x, where z is the zoom level, y is the tile's row number, and x in the tile's
column number. For example, in Figure 3-4, the map visualizer XYX storage scheme
shows the images (74.png, 75.png, 76,png, 77.png) in the tile columns for tile row 33 for
zoom level 8.
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3.2.2.4 Creating a Map Tile Layer Using an External Web Map Source
You can use an external web map source to create a map tile layer, as follows:
1.
Log in to the map visualizer administrative console.
2.
Click Create Tile Layer.
3.
Select External as this tile layer's map image source, and click Continue.
4.
On the Create a map tile layer for external map source page, enter the appropriate
information:
Name: Tile layer name. Example: TILELAYER1
Data Source: Name of the data source for the tile layer. Example MVDEMO
Max browser tile cache age (hours): Maximum number of hours in the cache
before a tile is refreshed. Example: 168
Map Service URL: Example: http://mycorp.com:7001/mapviewer/wms
Request Method: HTTP GET
Adapter class: oracle.lbs.mapcache.adapter.WMSAdapter
Jar file location: Example: adapterlibs/
Background: transparent
Adapter properties: (Check it and click Add multiple times as appropriate,
entering the values for the following each time.)
•
datasource: Example: mvdemo
•
version: 1.1.1
•
srs: EPSG:4326
•
layers: Example: THEME_DEMO_COUNTIES,THEME_DEMO_HIGHWAYS
•
format: image/png
•
transparent: true
Tile storage: Example: C:\temp
SRID: 8307
Min X: -180.0
Max X: 180.0
Min Y: -90.0
Max Y: 90.0
Tile width (pixels): 256
Tile height (pixels): 256
File format: PNG
# Zoom Levels: 10
Minimum map scale: 1000
Maximum map scale: 250000000
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5.
Click Submit to create the tile layer.
The message Information: New map tile layer created successfully is displayed.
To verify the created layer, you can click Manage Tile Layers on the left, select the
tile layer, and click View map / Manage tiles to preview the map.
3.2.3 Map Cache Auto-Update
The map cache auto-update feature periodically updates cached map tiles when they
become "dirty". A cached map tile becomes dirty when data in base tables is changed
by an update, insert, or delete operation, because such changes may affect the shape,
annotation, or choice of rendering style for the already cached map tiles.Updating a
dirty tile invokes one of the following operations: a) Refresh: delete the cached dirty
tiles and then re-fetch them; or b) Clear: only delete the cached dirty tiles. To enable
automatic updating for a tile layer, you perform the following major steps:
1.
Add the <dirty_tile_auto_update> element to the mapViewerConfig.xml
configuration file.
2.
Add the <auto_update> element to tile layer definition.
3.
Create the dirty MBR table, base tables' log table, and triggers.
To test the automatic tile updating, follow the instructions in Start the map visualizer
server and test the map cache auto-update feature.
•
Add the <dirty_tile_auto_update> element to the mapViewerConfig.xml
configuration file
•
Add the <auto_update> element to tile layer definition
•
Create the dirty MBR table, base tables' log table, and triggers
•
Start the map visualizer server and test the map cache auto-update feature
3.2.3.1 Add the <dirty_tile_auto_update> element to the mapViewerConfig.xml
configuration file
Add the <dirty_tile_auto_update> element as a child element of the <map_tile_server>
element. For example:
<map_tile_server>
<tile_storage default_root_path="/scratch/tilecache/"/>
<dirty_tile_auto_update
auto_update="true"
auto_update_interval="1"
recycle_interval="168"/>
</map_tile_server>
The auto_update attribute enables server's automatic update when set to true (the
default is false). If this attribute is set to true, all qualified tile layers on the server will
be automatically updated. To qualify, a tile layer must have a proper definition (see
Add the <auto_update> element to tile layer definition).
The auto_update_interval attribute sets the recurring interval for checking the base
tables' log table and the dirty MBR table. Its value is in minutes, and the default value
is 1. The value should not be more than a few minutes, and it should not be very large
(even if you update the base tables far less frequently, such as daily or weekly). The
base tables' log table and the dirty MBR table should be created before starting the
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map visualizer server. Sample scripts for creating these two tables and related
sequences and triggers are included in Create the dirty MBR table, base tables' log
table, and triggers.
The recycle_interval attribute specifies how long to keep a processed row in the log
table and dirty MBR table. Its value is in hours, and the default value is 168.
Processed rows older than that will be deleted.
When the map visualizer starts, it loads the <dirty_tile_auto_update> element from
mapViewerConfig.xml configuration file, and the element is applied to all tile layers of
this server. If that element is not found, then the server disables any tile layer's autoupdate capability.
3.2.3.2 Add the <auto_update> element to tile layer definition
Add an <auto_update> element after the <zoom_levels> element in a tile layer definition.
You can add this element manually or using the map visualizer web console. For
example:
<auto_update
finest_level_to_refresh="15"
dirty_mbr_batch="100"
dirty_mbr_cap="1000">
<dirty_mbr_table name="mbr_mcau"/>
<logtable name="log_mcau_tl"/>
</auto_update>
The finest_level_to_refresh attribute specifies the finest level to refresh. Levels
starting from level 0, level 1, level 2, …, until this specified level will be refreshed, and
dirty tiles in the remaining zoom levels will be cleared. If the data modifications in the
base tables are often geographically small features (as most data modifications should
be), such as changing the name of a restaurant or inserting a newly developed street,
the value can be the finest zoom level found in the tile layer definition. For example, if
there are 19 zoom levels from 0 to 18, then this attribute can be set to 18.
The dirty_mbr_batch attribute specifies the maximum number of rows from the dirty
MBR table for an update. The default value is 100. This value prevents the server from
getting a very large number of tiles to update at one time. Instead, if a large number of
dirty tiles need a refresh or clear operation, these tiles will be processed in many
updates, and one interval processes just one batch. To determine an optimal value for
this attribute, consider the following factors:
•
The auto_update_interval value (see Add the <dirty_tile_auto_update> element to
the mapViewerConfig.xml configuration file)and how many tiles the server is able
finish in the interval
•
The amount of memory that the server can use
•
The number of tile layers that are enabled for map cache auto update and the
frequency and magnitude of the changes in their base tables
Because there is no formula for a precise calculation of an optimal dirty_mbr_batch
value, the best practice is to set up an environment to test different settings. When
selecting a value, consider the worst case scenario. Two extreme scenarios to avoid
are: a) the value is so small that the server is idling after finishing a refresh operation
while the number of dirty MBR rows in the dirty MBR table keeps growing; or b) the
value is so large that the server runs out of memory, throws an out-of-memory
exception, and shuts down all services.
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The dirty_mbr_cap attribute specifies the maximum number of dirty tiles for a log table
to generate in one interval. This constraint may affect the finest zoom level for refresh
operation, and the remaining zoom levels are then set for a clear operation. The
accumulation counter for dirty tiles starts from zoom level 0, to level 1, level 2, and so
on, until the cap is reached or the finest level to refresh is reached.
When a cap is reached at level n before reaching the specified finest level to refresh,
the already counted tiles in level 0, level 1, level 2, …, and level n-1 are for a refresh
operation (delete and then re-fetch), and the current zoom level (level n in this
example) and all other finer levels are for a clear operation (delete from the map tile
cache and no re-fetch). For example, if the cap is given a value of 1000, the dirty tile
counter reaches the cap at zoom level 4, then all the counted dirty tiles from level 0 to
level 3 are for refresh. After that, each dirty tile in level 3 will be used to define a
rectangle (the rectangular area the tile covers on the ground), and this rectangle is
taken as an MBR to clear all zoom levels starting from level 4, level 5, and all other
finer levels in this tile layer.
The <dirty_mbr_table> element specifies the name of the dirty MBR table, where the
dirty MBRs are to be stored, retrieved, and updated. You need to manually create this
table before starting the map visualizer server (see the example in Create the dirty
MBR table, base tables' log table, and triggers).
The <logtable> element specifies the name of the base table's log table. If a tile layer
depends on more than one base table (as is often the case), then every change in
each base table should be inserted into this log table by its trigger; if the schema is
accessed by more than one data source defined in mapViewerConfig.xml, then one
change in a base table should insert one row for each data source.
It is recommended that each tile layer have its own log table and its own dirty MBR
table. Both tables should be manually created before starting the server (see the
example in Create the dirty MBR table, base tables' log table, and triggers).
3.2.3.3 Create the dirty MBR table, base tables' log table, and triggers
This section contains examples that, when taken together, show the actions to create
the dirty MBR table, base tables' log table, and triggers. The example segments
assume that a base map named DEMO_MAP is already defined and that there is one
data source named MVDEMO accessing the schema.
The example code segments include explanatory comments, and they perform the
following actions:
1.
Create a tile layer that includes an <auto_update> element.
insert into user_sdo_cached_maps values(
'MCAU_TL',
'a test case for map cache auto update',
'',
'YES',
'YES',
'<map_tile_layer name="MCAU_TL" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3" fetch_larger_tiles="false">
<internal_map_source data_source="mvdemo" base_map="DEMO_MAP"/>
<coordinate_system srid="8307" minX="-180.0" maxX="180.0" minY="-90.0"
maxY="90.0"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="2132.729583849784"
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max_scale="559082264.0287178">
</zoom_levels>
<auto_update
finest_level_to_refresh="15"
dirty_mbr_batch="100"
dirty_mbr_cap="1000">
<dirty_mbr_table name="mbr_MCAU_TL"/>
<logtable name="log_MCAU_TL"/>
</auto_update>
</map_tile_layer>',
'DEMO_MAP',
'');
commit;
2.
Create a dirty MBR table and its trigger.
The dirty MBR table stores the dirty MBRs for refresh and clear operations. This
table is populated using the geometries from the log table. There is also a
sequence and a trigger created for generating unique IDs for this table's ID
column.
-- create the dirty MBR table
CREATE TABLE mbr_MCAU_TL (
id
number,
datasource
varchar2(32),
tile_layer
varchar2(32),
logtable
varchar2(32),
refresh_status varchar2(1),
failed
clear_status varchar2(1),
failed
mbr_to_clear varchar2(1),
zoom_level
number,
mx
number,
my
number,
minx
number,
miny
number,
maxx
number,
maxy
number,
insert_time
Date,
update_time
Date
);
-------
dirty MBR table name
id, used for tracking the status
data source name
tile layer name
basetable's log-table
n: not refreshed, y: refreshed, p:pending, f:
-- n: not cleared,
-----------
y: cleared,
p:pending, f:
y/n: use tile's mbr for clearing finer levels
zoom level of this tile
mesh x ordinate
mesh Y ordinate
tile's minimum x coordinate
tile's minimum y coordinate
tile's maximum x coordinate
tile's maximum y coordinate
when the tile MBR was inserted into this table
most recent update (refresh/clear) time
-- create a sequence for mbr_MCAU_TL
CREATE SEQUENCE mbr_MCAU_TL_seq
START WITH 1
INCREMENT BY 1
CYCLE
MAXVALUE 9999999999;
-- create a trigger to get a unique id
create or replace trigger mbr_MCAU_TL_br
before insert on mbr_MCAU_TL -- before inserting the row
referencing new as new old as old
for each row -- for each row
begin
select mbr_MCAU_TL_seq.nextval INTO :new.id FROM dual;
end;
/
3.
Create a log table.
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The base tables' log table is for recording the rows changed in the base tables of
the tile layer. Because each tile layer depends on the data in its base tables when
generating a map tile, any change made to the base table (such as modifications
of geometries or changes to attributes values) may affect their representation in
their corresponding map tile. The change log table records such changes through
a trigger created on its base table.
The following statements create a log table, a sequence, and a trigger on the table
using the sequence to generate unique ID values.
-- create the log table
create table log_MCAU_TL(
id number,
geomO sdo_geometry, -- the affected geometry or its attributes, original
geometry
geomN sdo_geometry, -- the affected geometry or its attributes, new geometry
modified Date,
-- when the modified occurred
status varchar2(1), -- y: processed, n: not processed
datasource varchar2(32), -- data source name, more than one ds may access the
same log
tile_layer varchar2(32), -- tile layer name
basetable varchar2(32) -- base table name, more than one base table may
insert into this log
);
-- create a sequence for log_MCAU_TL
CREATE SEQUENCE log_MCAU_TL_seq
START WITH 1
INCREMENT BY 1
CYCLE
MAXVALUE 9999999999;
-- create a trigger for log_MCAU_TL to create a unique id
create or replace trigger log_MCAU_TL_br
before insert on log_MCAU_TL -- before inserting
referencing new as new old as old
for each row
-- for each row
begin
select log_MCAU_TL_seq.nextval INTO :new.id FROM dual;
end;
/
4.
Create a trigger on each base table to insert changes into the log table.
In a base table's trigger, any geometries inserted into the log table are transformed
into the same spatial reference system (coordinate system) as the tile layer. If
there are multiple data sources defined in the mapViewerConfig.xml configuration
file accessing the same schema, then one INSERT statement should be used for
each of these data sources in each trigger definition.
The following statements make these assumptions:
•
One data source named MVDEMO is accessing the schema that contains the
MCAU_TL tile layer. (Thus, there is only one INSERT statement in each
trigger definition.)
•
The tile layer's spatial reference system (SRID) is 8307 (WGS 84 longitude/
latitude).
•
There are four base tables to monitor for this tile layer: states, counties,
interstates, and cities.
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--states trigger
create or replace trigger states_MCAU_TL_ar
after insert or update or delete on states -- any change
referencing new as new old as old
for each row
when (old.geom IS NOT NULL OR new.geom IS NOT NULL)
declare
oldGeom SDO_GEOMETRY;
newGeom SDO_GEOMETRY;
tileSRID number;
begin
tileSRID := 8307;
oldGeom := :old.geom;
if (:old.geom IS NOT NULL) then
if (:old.geom.SDO_SRID != tileSRID) then
select sdo_cs.transform(:old.geom, tileSRID) into oldGeom from dual;
end if;
end if;
newGeom:=:new.geom;
if (:new.geom IS NOT NULL) then
if (:new.geom.SDO_SRID!= tileSRID) then
select sdo_cs.transform(:new.geom, tileSRID) into newGeom from dual;
end if;
end if;
insert into log_MCAU_TL (id, geomO, geomN, modified, status, datasource,
tile_layer, basetable)
values(null, oldGeom, newGeom, sysdate, 'n', 'MVDEMO', 'MCAU_TL',
'states');
end;
/
--counties trigger
create or replace trigger counties_MCAU_TL_ar
after insert or update or delete on counties
referencing new as new old as old
for each row
when (old.geom IS NOT NULL OR new.geom IS NOT NULL)
declare
oldGeom SDO_GEOMETRY;
newGeom SDO_GEOMETRY;
tileSRID number;
begin
tileSRID := 8307;
oldGeom := :old.geom;
if (:old.geom IS NOT NULL) then
if (:old.geom.SDO_SRID!=tileSRID) then
select sdo_cs.transform(:old.geom, tileSRID) into oldGeom from dual;
end if;
end if;
newGeom:=:new.geom;
if (:new.geom IS NOT NULL) then
if (:new.geom.SDO_SRID!= tileSRID) then
select sdo_cs.transform(:new.geom, tileSRID) into newGeom from dual;
end if;
end if;
insert into log_MCAU_TL (id, geomO, geomN, modified, status, datasource,
tile_layer, basetable)
values(null, oldGeom, newGeom, sysdate, 'n', 'MVDEMO', 'MCAU_TL',
'counties');
end;
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/
--interstates trigger
create or replace trigger interstates_MCAU_TL_ar
after insert or update or delete on interstates
referencing new as new old as old
for each row
when (old.geom IS NOT NULL OR new.geom IS NOT NULL)
declare
oldGeom SDO_GEOMETRY;
newGeom SDO_GEOMETRY;
tileSRID number;
begin
tileSRID := 8307;
oldGeom := :old.geom;
if (:old.geom IS NOT NULL) then
if (:old.geom.SDO_SRID!=tileSRID) then
select sdo_cs.transform(:old.geom, tileSRID) into oldGeom from dual;
end if;
end if;
newGeom:=:new.geom;
if (:new.geom IS NOT NULL) then
if (:new.geom.SDO_SRID!= tileSRID) then
select sdo_cs.transform(:new.geom, tileSRID) into newGeom from dual;
end if;
end if;
insert into log_MCAU_TL (id, geomO, geomN, modified, status, datasource,
tile_layer, basetable)
values(null, oldGeom, newGeom, sysdate, 'n', 'MVDEMO', 'MCAU_TL',
'interstates');
end;
/
--cities trigger
create or replace trigger cities_MCAU_TL_ar
after insert or update or delete on cities
referencing new as new old as old
for each row
when (old.location IS NOT NULL OR new.location IS NOT NULL)
declare
oldGeom SDO_GEOMETRY;
newGeom SDO_GEOMETRY;
tileSRID number;
begin
tileSRID := 8307;
oldGeom := :old.location;
if (:old.location IS NOT NULL) then
if (:old.location.SDO_SRID!=tileSRID) then
select sdo_cs.transform(:old.location, tileSRID) into oldGeom from dual;
end if;
end if;
newGeom:=:new.location;
if (:new.location IS NOT NULL) then
if (:new.location.SDO_SRID!= tileSRID) then
select sdo_cs.transform(:new.location, tileSRID) into newGeom from dual;
end if;
end if;
insert into log_MCAU_TL (id, geomO, geomN, modified, status, datasource,
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tile_layer, basetable)
values(null, oldGeom, newGeom, sysdate, 'n', 'MVDEMO', 'MCAU_TL',
'cities');
end;
/
commit;
3.2.3.4 Start the map visualizer server and test the map cache auto-update
feature
To test the automatic tile updating, start the map visualizer server and then change
one or more rows in the base table.
1.
Modify a row in the base table. For example:
update cities set city='Worcester' where city='Worcester' and state_abrv='MA';
2.
Check the log table. For example:
select * from log_mcau_tl;
The result should include a row that was just inserted by the base table's trigger.
3.
Wait for about one interval (one minute in this example), then check the dirty MBR
table. For example:
select count(*) from mbr_mcau_tl;
The result should include some dirty MBR rows inserted by the server.
You can also look for changes in the refresh_status column in the dirty MBR table.
When rows are initially inserted, the status is set to n for not processed; then it
changes to p for pending when they are being processed; and after the update is done,
it changes to y for processed. Meanwhile, on the server you can see that the server
has been updating the tiles (the server's logger needs to be set to finest level to see
the finest logging information).
3.2.4 UTFGrid for Map Tiles: Including Text Information About
Features
When a tile layer has UTFGrid enabled, a data set named UTFGrid becomes a
"companion" of an image tile, containing text information about features in the image
tile. This text information can be displayed by the browser when responding to a
mouse event, such as mouse click on a map feature.
A UTFGrid data set is stored in JSON format, and has two components: (a) a grid data
set that mirrors its companion image tile, and (b) attributes of all grid cells. The value
at each grid cell serves as the key to link the image tile cell and its attributes. Each
image pixel on a map is associated with a UTFGrid grid cell, and the cell's value
indicates where its attributes (as text strings) can be retrieved. For storage efficiency,
the value of each grid cell is encoded in a revised UTF-8 encoding scheme.
•
Enabling the UTFGrid Option for a Tile Layer
•
Encoding a Key and Decoding a Grid Cell's Value
•
Building a UTFGrid Test Case
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3.2.4.1 Enabling the UTFGrid Option for a Tile Layer
To enable the UTFGrid option for a map tile layer, then in the
USER_ADO_CACHED_MAPS row for the tile layer, specify utfgrid="true" in the
<map_tile_layer> element, and optionally specify the UTFGrid resolution with the
utfgrid_resolution attribute (the default is 4). For example:
insert into user_sdo_cached_maps values(
'UTFGRID_TL',
'utfgrid enalbled test case ',
'',
'YES',
'YES',
'<map_tile_layer name="UTFGRID_TL" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3" fetch_larger_tiles="false"
persistent_tiles="true" utfgrid="true" utfgrid_resolution="4">
<internal_map_source data_source="mvdemo" base_map="UTFGRID_BASEMAP"
bgcolor="#dddddd" out_of_bounds_color="#eeddff"/>
<tile_storage root_path="/temp" xyz_storage_scheme="true"/>
<coordinate_system srid="8307" minX="-180.0" maxX="180.0" minY="-90.0"
maxY="90.0"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="2132.729583849784"
max_scale="559082264.0287178">
</zoom_levels>
</map_tile_layer>',
'UTFGRID_BASEMAP',
'');
commit;
The utfgrid_resolution attribute determines how fine the grid cells are in an UTFGrid
data set, and the default value of 4 indicates that one grid cell represents 4 by 4 image
pixels in its companion image tile. For example, if 256x256 is an image's dimension,
then the grid's dimension will be 64x64, and a grid cell at row=10, column=20
represents the pixels in the tile image from row 40 to row 43 and from column 80 to
column 83 (note that one grid cell represents 16 image tile pixels). When multiple
features in the map image tile fall into one grid cell at the indicated resolution, then the
feature with the majority or plurality of the pixels is assigned to the grid cell. The value
stored in the grid cell is encoded using UTF-8 encoding.
If a tile layer has UTFGrid enabled, when the map server generates a map image tile,
it will also generate an UTFGrid data set stored in JSON format. When a client
requests a map image tile, both the image tile and its UTFGrid JSON file will be
returned in the response.
In the map visualizer server, the UTFGrid JSON files are stored in the same location
with their image tiles. For example, if an image tile is cached at /mapcache/
MVDEMO.UTFGRID_TL/0/1/2.PNG, you should also see its companion UTFGrid file /
mapcache/MVDEMO.UTFGRID_TL/0/1/2.JSON.
This UTFGrid option is currently not supported if the image tiles are stored in a
database table (see Store the tiles in a database table ) when disk cache is disabled
for a tile layer (see Stream the tiles directly without storing them ).
3-38
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3.2.4.2 Encoding a Key and Decoding a Grid Cell's Value
A tile layer can contain multiple data layers or themes. Each theme will have its own
grid data set, and an UTFGrid JSON object may contain multiple grid data sets. In
each theme's grid, features shown in its image tile are also "drawn" using styles to
render each feature. As for its associated image tile, a feature is drawn using its key,
and the key is an ordinal number assigned to each feature. This number is used to
assign a UTF-8 encoded value for the cell's value.
When a mouse event is triggered on a feature in an image tile, the image pixel's
corresponding grid cell can be located, and the cell's value (an UTF-8 encoded value)
can then be retrieved. This UTF-8 encoded value can then be decoded to derive its
key, an ordinal number. Using this key, the attribute stored can be obtained. (See the
examples near the end of Building a UTFGrid Test Case.)
3.2.4.3 Building a UTFGrid Test Case
This test case focuses on the server side. It has two major steps: creating a UTFGridenabled tile layer, and sending some hard-coded requests to the server. (In a real
application, you need to have a client side map application to make use of the tile
layer.)
1.
Create a UTFGrid-enabled tile layer.
If all the spatial base tables and styles exist in the metadata, the following example
creates four themes, a basemap, and an UTFGrid-enabled tile layer. Because the
feature attributes stored in an UTFGrid JSON object come from the <hidden_info>
element of a theme, the <hidden_info> element is defined in three of the four
themes. (If none of the four themes has the <hidden_info> element defined, then
enabling this tile layer's UTFGrid option would not make sense, because the
UTFGrid object would be empty and creating it would still consume server
resources.)
-- insert theme 1
insert into USER_SDO_THEMES (name, description, base_table, geometry_column,
styling_rules)
values (
'UTFGRID_THEME_DEMO_STATES',
'for utfgrid testing',
'STATES',
'GEOM',
'<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="STATE" name="State"/>
<field column="STATE_ABRV" name="Abrv."/>
<field column="TOTPOP" name="Population"/>
</hidden_info>
<rule>
<features style="C.S02_COUNTRY_AREA"> </features>
<label column="STATE_ABRV" style="T.S02_STATE_ABBREVS"> 1 </label>
</rule>
</styling_rules>');
-- insert theme 2
insert into USER_SDO_THEMES (name, description, base_table, geometry_column,
styling_rules)
3-39
Chapter 3
Map Tile Server
values (
'UTFGRID_THEME_DEMO_COUNTIES',
'for utfgrid testing',
'COUNTIES',
'GEOM',
'<?xml version="1.0" standalone="yes"?>
<styling_rules>
<!--<hidden_info>
<field column="COUNTY" name="County"/>
<field column="FIPSSTCO" name="Fips"/>
<field column="TOTPOP" name="Population"/>
<field column="STATE_ABRV" name="State"/>
</hidden_info>-->
<rule>
<features style="L.S06_BORDER_STATE"> </features>
</rule>
</styling_rules>');
-- insert theme 3
insert into USER_SDO_THEMES (name, description, base_table, geometry_column,
styling_rules)
values (
'UTFGRID_THEME_DEMO_HIGHWAYS',
'for utfgrid testing',
'INTERSTATES',
'GEOM',
'<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="HIGHWAY" name="Highway"/>
<field column="ROUTEN" name="No."/>
</hidden_info>
<rule>
<features style="L.S04_ROAD_INTERSTATE"> </features>
<label column="routen" style="M.HWY_USA_INTERSTATE_NARROW"> (3length(routen)) </label>
</rule>
</styling_rules>');
-- insert theme 4
insert into USER_SDO_THEMES (name, description, base_table, geometry_column,
styling_rules)
values (
'UTFGRID_THEME_DEMO_CITIES',
'for utfgrid testing',
'CITIES',
'LOCATION',
'<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="CITY" name="City"/>
<field column="POP90" name="Population"/>
</hidden_info>
<rule>
<features style="M.ALL_CITY_L2"> (pop90 between 200000 AND 1000000 ) </
features>
<label column="city" style="T.S07_CITIES_L2"> 1 </label>
</rule>
<rule>
<features style="M.ALL_CITY_L3"> (pop90 between 0 and 200000) </features>
<label column="city" style="T.S07_CITIES_L3"> 1 </label>
3-40
Chapter 3
Map Tile Server
</rule>
</styling_rules>');
-- insert a basemap
INSERT INTO USER_SDO_MAPS (name, description, definition)
values (
'UTFGRID_BASEMAP',
'for utfgrid testing',
'<?xml version="1.0" standalone="yes"?>
<map_definition>
<theme name="UTFGRID_THEME_DEMO_STATES" min_scale="1.5E8" max_scale="0.0"
scale_mode="RATIO"/>
<theme name="UTFGRID_THEME_DEMO_COUNTIES" min_scale="8500000.0"
max_scale="0.0" scale_mode="RATIO"/>
<theme name="UTFGRID_THEME_DEMO_HIGHWAYS" min_scale="4.5E7" max_scale="0.0"
scale_mode="RATIO"/>
<theme name="UTFGRID_THEME_DEMO_CITIES" min_scale="7500000.0"
max_scale="0.0" scale_mode="RATIO"/>
</map_definition>' );
-- insert the UTFGrid enabled tile layer
insert into user_sdo_cached_maps values(
'UTFGRID_TL',
'a utfgrid ',
'',
'YES',
'YES',
'<map_tile_layer name="UTFGRID_TL" image_format="PNG"
http_header_expires="168.0" concurrent_fetching_threads="3"
fetch_larger_tiles="false"
persistent_tiles="true" utfgrid="true" utfgrid_resolution="8">
<internal_map_source data_source="mvdemo" base_map="UTFGRID_BASEMAP"
bgcolor="#dddddd" out_of_bounds_color="#eeddff"/>
<tile_storage root_path="/temp" xyz_storage_scheme="true"/>
<coordinate_system srid="8307" minX="-180.0" maxX="180.0" minY="-90.0"
maxY="90.0"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="2132.729583849784"
max_scale="559082264.0287178">
</zoom_levels>
</map_tile_layer>',
'UTFGRID_BASEMAP',
'');
commit;
2.
Request the map image and its UTFGrid object.
In an actual application, requesting a map image tile and its companion UTFGrid
JSON file is handled by the map visualizer HTML5 API; however, for illustration
purposes, two substeps with hard-coded requests are shown here.
a.
Request an image tile from the server. For example:
http://localhost:8080/mapviewer/mcserver?
request=gettile&format=png&zoomlevel=8&mapcache=MVDEMO.UTFGRID_TL&mx=77&my
=94
The server's response:
3-41
Chapter 3
Map Tile Server
b.
Request the image tile's companion UTFGrid from the server. For example:
http://localhost:8080/mapviewer/mcserver?
request=getutfgrid&format=json&zoomlevel=8&mapcache=MVDEMO.UTFGRID_TL&mx=7
7&my=94
The server's response:
{"UTFGRID_THEME_DEMO_STATES":
{"keys":["1","2","3"],
"data":{
"1":{"State":"New Hampshire","Abrv.":"NH","Population":"1109252"},
"2":{"State":"Maine","Abrv.":"ME","Population":"1227928"},
"3":{"State":"Massachusetts","Abrv.":"MA","Population":"6016424"}},
"grid":[
"!!!!!!!!!!!!!!!!!###############",
"!!!!!!!!!!!!!!!!!###############",
"!!!!!!!!!!!!!!!!!############## ",
"!!!!!!!!!!!!!!!!!###############",
"!!!!!!!!!!!!!!!!!############## ",
"!!!!!!!!!!!!!!!!!############# ",
"!!!!!!!!!!!!!!!!!!#########
",
"!!!!!!!!!!!!!!!!!!!########
",
"!!!!!!!!!!!!!!!!!!!!#######
",
"!!!!!!!!!!!!!!!!!!!!######
",
"!!!!!!!!!!!!!!!!!!!!######
",
"!!!!!!!!!!!!!!!!!!!!!!###
",
"!!!!!!!!!!!!!!!!!!!!!!!#
",
"!!!!!!!!!!!!!!!!!!!!!!!
",
"!!!!!!!!!!!!!!!!!!!!!!
",
"!!!!!!!!!!!!!!!!!!!!!!
",
"!!!!!!!!!!!!!!!!!$$!!
",
"!!!!!!!!!!!!!!!$$$$$$
",
"!!!!!!!!!!!!$$$$$$$$$
",
"!!!!!!!!!!!$$$$$$$$$$$
",
"$$$$$!!!!$$$$$$$$$$$$$$ $$
",
"$$$$$$$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$
",
3-42
Chapter 3
Map Tile Server
"$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$$$
",
"$$$$$$$$$$$$$$$$$$$$$$$
"]},
"UTFGRID_THEME_DEMO_HIGHWAYS":{
"keys":["1","2","3","4","5","6","7","8","9"],
"data":{
"1":{"Highway":"I 93","No.":"93"},
"2":{"Highway":"I 95","No.":"95"},
"3":{"Highway":"I 89","No.":"89"},
"4":{"Highway":"I 293","No.":"293"},
"5":{"Highway":"I 495","No.":"495"},
"6":{"Highway":"I 190","No.":"190"},
"7":{"Highway":"88","No.":"99"},
"8":{"Highway":"I 290","No.":"290"},
"9":{"Highway":"I 90","No.":"90"}},
"grid":[
" !
## ",
" !
### ",
" !!
## ",
" !!
##
",
" !
##
",
" !
##
",
" !!
##
",
" !!
##
",
"$ !!
#
",
"$$$$!
##
",
"
!!
###
",
"
!
###
",
"
%!
##
",
"
%!!
##
",
"
%%!
#
",
"
!!
##
",
"
!!
##
",
"
!! &&&&#
",
"
!! &&& ##
",
"
!! & #
",
"
!&& ##
",
"
&&&! ##
",
"
&&&& ! ##
",
"
&&&&
!! ##
",
"' &&&
##!###
",
"' &&&
#((!!
",
" &&
#( !!
",
" &&
( !!!
",
")))& *********!
",
") &***** ## !
",
"*****
## !
",
"***&&
##!!!
"]},
"UTFGRID_THEME_DEMO_CITIES":{
"keys":["1","2"],
"data":{
"1":{"City":"Lowell","Population":"103439"},
"2":{"City":"Boston","Population":"574283"}},
"grid":[
"
",
"
",
"
",
"
",
"
",
"
",
3-43
Chapter 3
Map Tile Server
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
",
"
!!
",
"
",
"
",
"
",
"
",
"
",
"
",
"
##
",
"
",
"
",
"
"]},
"resolution":"8","rows":"32","columns":"32"}
The preceding response shows a UTFGrid object that contains properties for
the themes UTFGRID_THEME_DEMO_STATES, UTFGRID_THEME_DEMO_HIGHWAYS, and
UTFGRID_THEME_DEMO_CITIES. (The theme UTFGRID_THEME_DEMO_COUNTIES did not
define the <hidden_info> element, and so nothing about that theme is listed in
the response.)
3.2.5 External Map Source Adapter
An external map source adapter is the interface between a map tile server and an
external map services provider. When a map image tile needs to be fetched from the
external map services provider, the map tile server calls the adapter with information
about the zoom level, size, and location of the tile. The adapter then constructs a
provider-specific request, sends the request to the external map services provider, and
return the resulting image tile to the map tile server.
The external map source adapter is a Java class that must extends the abstract Java
class oracle.mapviewer.share.mapcache.MapSourceAdapter, which is defined as follows:
public abstract class MapSourceAdapter
{
public abstract String getMapTileRequest(TileDefinition tile);
public byte[] getTileImageBytes(TileDefinition tile) ;
public Properties getProperties() ;
}
An adapter that extends this class must implement the following method:
•
public String getMapTileRequest(TileDefinition tile)
This method should implement the logic to construct the HTTP request string that
can be sent to the map services provider to fetch the map image tile. For example,
3-44
Chapter 3
Map Tile Server
if the URL of a map tile is http://myhost/mymapserver?par1=v1&par2=v2&par3=v3, the
HTTP request string returned by this method should be par1_v1&par2=v2&par3=v3.
When the map tile server cannot find a specific map tile, it calls the
getTileImageBytes method to fetch the binary data of the tile image, and that
method calls the getMapTileRequest method to construct the map tile request
before fetching the tile. The getMapTileRequest method takes one parameter: a
TileDefinition object that specifies the zoom level, bounding box, image size and
image format of the requested tile. This method returns the HTTP request string.
The map source adapter also inherits all methods implemented in class
MapSourceAdapter. Among them, the following methods are more important than the
others:
•
public byte[] getTileImageBytes(TileDefinition tile)
This method fetches the actual binary map tile image data from the external map
service provider. This method is already implemented. It calls the abstract method
getMapTileRequest to construct the map tile request and sends the request to the
external map services provider. If the map tiles cannot be fetched by sending
HTTP requests, you can override this method to implement the appropriate logic to
fetch an image tile from the map source. This method takes one parameter: a
TileDefinition object that specifies the zoom level, bounding box, image size, and
image format of the requested tile. This method returns the binary tile image data
encoded in the image format specified in the map tile layer configuration settings.
•
public Properties getProperties()
This method returns the provider-specific parameters defined in the map tile layer
configuration settings explained in Map Tile Layer Configuration.
The MapSourceAdapter and TileDefinition classes are packaged inside mvclient.jar,
which can be found under the directory $MAPVIEWER_HOME/web/WEB/lib.
Example 3-5 shows an external map source adapter.
Example 3-5
External Map Source Adapter
/**
* This is a sample map source adapter that can be used to fetch map
* tiles from a map visualizer instance.
*/
package mcsadapter ;
import
import
import
import
import
import
java.awt.Dimension;
java.net.URL;
java.util.Properties;
oracle.lbs.mapclient.MapViewer;
oracle.lbs.mapcommon.MapResponse;
oracle.mapviewer.share.mapcache.*;
/**
* The map source adapter must extend class
* oracle.lbs.mapcache.cache.MapSourceAdapter.
*/
public class MVAdapter extends MapSourceAdapter
{
/**
* Gets the map tile request string that is to be sent to the map
* service provider URL.
* @param tile tile definition
3-45
Chapter 3
Map Tile Server
* @return request string
*/
public String getMapTileRequest(TileDefinition tile)
{
// Get map source specified parameters
Properties props = this.getProperties() ;
String dataSource = props.getProperty("data_source") ;
String baseMap = props.getProperty("base_map") ;
// Use oracle.lbs.mapclient.MapViewer to construct the request string
MapViewer mv = new MapViewer(this.getMapServiceURL()) ;
mv.setDataSourceName(dataSource);
mv.setBaseMapName(baseMap);
mv.setDeviceSize(new Dimension(tile.getImageWidth(),
tile.getImageHeight()));
mv.setCenterAndSize(tile.getBoundingBox().getCenterX(),
tile.getBoundingBox().getCenterY(),
tile.getBoundingBox().getHeight());
int format = MapResponse.FORMAT_PNG_STREAM ;
String req = null ;
switch(tile.getImageFormat())
{
case TileDefinition.FORMAT_GIF:
mv.setImageFormat(MapResponse.FORMAT_GIF_URL);
req = mv.getMapRequest().toXMLString().replaceFirst(
"format=\"GIF_URL\"", "format=\"GIF_STREAM\"") ;
break ;
case TileDefinition.FORMAT_PNG:
mv.setImageFormat(MapResponse.FORMAT_PNG_URL);
req = mv.getMapRequest().toXMLString().replaceFirst(
"format=\"PNG_URL\"", "format=\"PNG_STREAM\"") ;
break ;
case TileDefinition.FORMAT_JPEG:
mv.setImageFormat(MapResponse.FORMAT_JPEG_URL);
req = mv.getMapRequest().toXMLString().replaceFirst(
"format=\"JPEG_URL\"", "format=\"JPEG_STREAM\"");
break ;
}
byte[] reqStr = null ;
try
{
reqStr = req.getBytes("UTF8") ;
}
catch(Exception e)
{}
// Return the request string.
return "xml_request="+ new String(reqStr);
}
}
Example 3-6 shows the implementation of the MapSourceAdapter.getTileImageBytes
method.
Example 3-6
MapSourceAdapter.getTileImageBytes Implementation
/**
* Fetches the map image tile from the external map service provider by
* sending the HTTP map tile request to the map service provider, and
* return the binary tile image data. You can rewrite this method so that
* the adapter can fetch the tile from an external map service provider
* that does not accept HTTP requests at all.
3-46
Chapter 3
Map Tile Server
* @param tile the tile definition
* @return the binary tile image data.
* @throws Exception
*/
public byte[] getTileImageBytes(TileDefinition tile)
throws Exception
{
// construct request string
String request = getMapTileRequest(tile) ;
if(request == null)
{
throw new Exception("Null map tile request string in map source adapter!") ;
}
// set proxy settings
Proxy proxy = null ;
/* If the proxyHost is "NONE", the request is sent directly to the
* external server. If the proxyHost is a valid host, that host will
* be used as the proxy server. If the proxyHost is empty of omitted,
* the global proxy setting in mapViewerConfig.xml will be in effect.
*/
boolean noProxy = "NONE".equalsIgnoreCase(getProxyHost()) ;
if(getProxyHost()!=null && !noProxy)
{
SocketAddress addr = new InetSocketAddress(proxyHost, proxyPort);
proxy = new Proxy(Proxy.Type.HTTP, addr);
}
// send the request and get the tile image binary
PrintWriter wr = null ;
BufferedInputStream bis = null;
try
{
String urlStr = mapServiceURL ;
if("GET".equalsIgnoreCase(httpMethod))
urlStr = mapServiceURL + "?" + request ;
log.finest("http "+httpMethod+": "+urlStr);
URL url = new URL(urlStr);
// Open a URL connection based on current proxy setting
URLConnection conn =
proxy!=null? url.openConnection(proxy):
(noProxy? url.openConnection(Proxy.NO_PROXY):
url.openConnection()) ;
conn.setConnectTimeout(timeOut);
if("GET".equalsIgnoreCase(getHTTPMethod()))
conn.connect();
else
{
conn.setDoOutput(true);
wr = new PrintWriter(conn.getOutputStream());
wr.print(request);
wr.flush();
wr.close();
wr = null ;
}
bis = new BufferedInputStream(conn.getInputStream());
byte[] result = toBytes(bis) ;
bis.close();
3-47
Chapter 3
Map Tile Server
bis = null ;
return result;
}
catch(Exception ioe)
{
throw new Exception("Failed to fetch external map tile.", ioe);
}
finally
{
try
{
if(bis != null)
{
bis.close();
bis = null;
}
if(wr != null)
{
wr.close();
wr = null;
}
}
catch(IOException ioee)
{
throw ioee;
}
}
}
3-48
4
Oracle Maps
Oracle Maps is the name for a suite of technologies for developing high-performance
interactive web-based mapping applications.
Oracle Maps is included with the map visualization component.
Topics:
•
Oracle Maps JavaScript API
The Oracle Maps JavaScript client is a browser-based map visualization engine
that works on top of the map tile server and that uses HTML5 technology.
•
Developing Oracle Maps Applications
This topic describes how to develop Oracle Maps applications.
•
Using Google Maps and Bing Maps
Applications can display Google Maps tiles or Microsoft Bing Maps tiles as a builtin map tile layer, by creating and adding to the map window an instance of
MVGoogleTileLayer or MVBingTileLayer, respectively.
•
Transforming Data to a Spherical Mercator Coordinate System
Popular online map services such as Google Maps and Microsoft Bing Maps use a
spherical Mercator projection for their maps.
•
Using Dynamic Tile Layers
A dynamic tile layer is a tile layer defined on the client side.
4.1 Oracle Maps JavaScript API
The Oracle Maps JavaScript client is a browser-based map visualization engine that
works on top of the map tile server and that uses HTML5 technology.
It implements the following functions:
•
Fetching map tiles from the map tile server and displaying them as a map tile layer
in the web browser.
•
Controlling user interaction, such as dragging for map navigation, clicking features,
drawing rectangles, and redlining.
Drawing a rectangle refers to the application user creating a rectangle by clicking
and holding the mouse button at one corner of the rectangle, dragging the mouse
to the diagonally opposite corner, and releasing the mouse button.
Redlining refers to the application user creating a polygon or polyline by clicking
the mouse button and then moving the mouse and clicking multiple times, with
each click extending the redline by a straight line. (Redline drawings are often
rendered in red, although you can specify a line style that uses any color.)
To access these functions, use the JavaScript API, which consists of several
JavaScript classes. For detailed information about all classes in the Oracle Maps
JavaScript API ), see the Javadoc-style reference documentation, which is included in
4-1
Chapter 4
Oracle Maps JavaScript API
the mvdemo.ear file and is available at the following location: http://host:port/
mvdemo/api/oracle_maps_html5_api.jsp
Tutorials and demos for the API are available as a standalone packaged application
with the root context path /mvdemo. The tutorials start with the basics (display a map tile
layer, add a navigation panel, display interactive features and information windows)
and move on to more complex topics such as registering event listeners,
programmatically creating and using styles, and spatial filtering.
The tutorials are all based on the MVDEMO sample data set (available from the map
visualization component page on the Oracle Technology Network) and assume a data
source named mvdemo. The tutorial page has three panels. The left one lists the sample
code, or demo, titles. Click on one and a map, or the result of executing that sample
code, is displayed in the top right panel. The bottom panel has tabs titled JavaScript
and HTML, which respectively show the JavaScript and HTML code fragments for the
selected demo.
•
About the Oracle Maps JavaScript API
4.1.1 About the Oracle Maps JavaScript API
The Oracle Maps JavaScript API takes advantage of the capabilities of modern
browsers and HTML5. Some of its features include:
•
Built-in support of various third party map tile services, such as maps.oracle.com,
Nokia Maps, Bing Maps, OpenStreet Maps, and other mapping service providers
•
Rich client side rendering of geospatial data with on-the-fly application of rendering
styles and effects such as gradients, animation, and drop-shadows
•
Autoclustering of large number of points and client side heat map generation
•
Client side feature filtering based on attribute values as well as spatial predicates
(query windows)
•
A rich set of built-in map controls and tools, including a customizable navigation
bar and information windows, configurable layer control, and red-lining and
distance measurement tools
Existing server-side predefined styles and themes will work with the API. For example,
the following code snippet creates an interactive vector layer based on a predefined
theme mvdemo.customers, which has an associated predefined style:
var baseURL = "http://"+document.location.host+"/mapviewer";
var layer = new OM.layer.VectorLayer("layer1",
{
def:{
type:OM.layer.VectorLayer.TYPE_PREDEFINED,
dataSource:"mvdemo",
theme:"customers",
url: baseURL
}
});
The API has the following top-level classes and subpackages, all of which are in the
namespace OM:
•
The Map class is the main class of the API.
•
The Feature class represents individual geo features.
4-2
Chapter 4
Oracle Maps JavaScript API
•
The MapContext class a top-level class encapsulating some essential contextual
information, such as the current map center point and zoom level. It is typically
passed into event listeners.
•
The control package contains all the map controls, such as navigation bar and
overview map.
•
The event package contains all the map and layer event classes.
•
The filter package contains all the client-side filters (spatial or relational) for
selecting, or subsetting, the displayed vector layer features.
•
The geometry package contains various geometry classes.
•
The layer package contains various tile and vector layer classes. The tile layer
classes include access to a few online map services such as Oracle, Nokia, Bing,
and OpenStreetMap. The vector layers are interactive feature layers.
•
The infowindow package contains the customizable information windows and their
styles.
•
The style package contains styles applicable to vector data on the client side. It
also includes visual effects such as animation, gradients, and drop shadows.
•
The tool package contains various map tools such as for distance measuring, redlining, and geometry drawing.
•
The universe package contains built-in, or predefined, map universes. A map
universe defines the bounding box and set of zoom level definitions for the map
content.
•
The util package contains various utility classes.
•
The visualfilter package provides an interface for the various visual effects, such
as gradients and drop shadows.
OM.Map is the main entry class for all map operations inside the web browser. This and
other classes provide interfaces for adding application-specific logic, operations, and
interactivity in web mapping applications. The application logic and operations can
include the following:
•
Create a map client instance and associate it with the map container DIV object
created in the web page.
•
Configure map parameters such as map center and map zoom level.
•
Optionally, create and manipulate map tile layers. A map tile layer is not required.
An application can have only interactive vector layers using a custom Universe
that programmatically defines the zoom levels and scales.
•
Create and manipulate vector layers.
•
Display an information window on the map.
•
Create fixed map decorations, such as a map title, a copyright note, and map
controls.
•
Access built-in utilities such as a navigation panel, rectangle or circle tool, scale
bar, and overview map panel.
•
Use event listeners to customize event handling and thus map interactions.
Other notes and considerations on using the Oracle Maps API:
4-3
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Developing Oracle Maps Applications
•
The "FOI server" in a previous version of the API is now a data server that streams
the vector geometries and attributes for features to the client for local rendering.
Therefore, the "FOI layers" in a previous version are now called vector layers.
•
A background map tile layer is not required in order to display interactive vector
layers. For example, an application can display a thematic map of states (such as
color-filled by population quintile) with no background tile layer.
•
The API depends on and includes JQuery and JQueryUI. So, oraclemapsv2.js
includes jquery-1.7.2.min.js and jquery-ui-1.8.16.min.js. If your application also
uses JQuery and JQueryUI and includes them already, then use the file
oraclemapsv2_core.js in the <script> tag instead to load the Oracle Maps library.
That is, use the following:
<script src="/mapviewer/jslib/v2/oraclemapsv2_core.js"></script>
instead of:
<script src="/mapviewer/jslib/v2/oraclemapsv2.js"></script>
For information about developing applications using the API, see Developing Oracle
Maps Applications and the Oracle-supplied tutorials and demos.
4.2 Developing Oracle Maps Applications
This topic describes how to develop Oracle Maps applications.
If the underlying base map and layers are managed in an Oracle database, each map
tile layer displayed in the client application must have a corresponding database
metadata entry in the USER_SDO_CACHED_MAPS metadata view (described in
xxx_SDO_CACHED_MAPS Views) . Similarly, if an interactive layer is based on
database content, it must have a metadata entry in the USER_SDO_THEMES view
(described in Map Visualizer Metadata Views, especially xxx_SDO_THEMES Views).
These tile and interactive layers, and the styles and styling rules for them, can be
defined using the Map Builder tool (described in Oracle Map Builder Tool).
To develop Oracle Maps applications using the API, follow these basic steps:
1.
Import the oraclemapsv2.js library.
The API is provided in a single JavaScript library packaged as part of the map
visualization component EAR archive.
2.
After the map visualization component is deployed and started, load the library
through a <script> tag, for example:
<script type="text/javascript" url="http://localhost:8080/mapviewer/jslib/v2/
oraclemapsv2.js"/>
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Note:
If you need a specific jQuery version other than the one packaged in
oraclemapsv2.js (shown in the preceding example), then you can add your
preferred jQuery first, followed by a list of libraries. For example:
<script
<script
<script
<script
<script
<script
<script
src="your_preferred_jQuery_library_listed_here_first.js "></script>
src="v2/jquery/jquery.hammer-full.min.js"></script>
src="v2/jquery/jquery.i18n.properties-min-1.0.9.js"></script>
src="v2/jquery/jquery.mousewheel.min.js"></script>
src="v2/rtree/rtree-min.js"></script>
src="v2/fortknox-libs/fortknox-canvas.js"></script>
src="v2/oraclemapsv2_core.js"></script>
3.
Create a <DIV> tag in the HTML page, which will contain the interactive map.
4.
Create a client-side map instance that will handle all map display functions.
The class is named OM.Map and is the main entry point of the API.
5.
Set up a map universe (unless you also do the optional next step).
A map universe basically defines the overall map extent, the number of zoom
levels, and optionally the resolution (in map units per pixel) at each zoom level.
Note that a predefined tile layer is not necessary in order to display interactive
vector layers or themes. For example, an interactive thematic map of sales by
region does not need to have a background map, or tile layer.
6.
(Optional) Add a tile layer that serves as the background map.
The tile layer can be from the database, such as mvdemo.demo_map, or from a
supported service, such as Nokia Maps. Adding a tile layer also implicitly defines a
map universe, and therefore the preceding step (setting up a map universe) is not
necessary in this case.
7.
Add one or more interactive vector layers.
OM.VectorLayer uses HTML5 (Canvas or SVG) technology to render all the data in
the browser. So, unless specified otherwise, all vector layer content is loaded once
and there are no subsequent database queries, or data fetching, on map zoom or
pan operations.
8.
Add one or more map controls, tools, and other application-specific UI controls so
that users can set the displayed layers, styling, and visual effects.
If you need to prevent themes from being streamed by default, you must protect them
is by adding authentication, that is, by adding a security constraint in the map
visualization component web.xml file and by configuring the mds.xml file to authorize
access to various themes. For information, see Configuring and Securing the Map
Data Server for the HTML5 API.
For detailed instructions and related information about using the API, see the Oraclesupplied tutorials and demos.
•
Creating the Client Application with the API
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Developing Oracle Maps Applications
4.2.1 Creating the Client Application with the API
Oracle Maps applications run inside web browsers and require only HTML5 (Canvas)
support and JavaScript enabled. No additional plugins are required.
The source for an Oracle Maps application is typically packaged in an HTML page,
which consists of the following parts:
•
A <script> element that loads the Oracle Maps client library into the browser's
JavaScript engine. For example:
<script src="/mapviewer/jslib/v2/oraclemapsv2.js"></script>
•
An HTML <div> element that will contain the map. For example:
<div id="map" style="width: 600px; height: 500px"></div>
•
JavaScript code that creates the map client instance and sets the initial map
content (tile and vector layer), the initial center and zoom, and map controls. This
code should be packaged inside a function which is executed when the HTML
page is loaded or ready. The function is specified in the onload attribute of the
<body> element of the HTML page. For example:
function on_load_mapview()
{
var baseURL = "http://"+document.location.host+"/mapviewer";
// Create an OM.Map instance to display the map
var mapview = new OM.Map(document.getElementById("map"),
{
mapviewerURL:baseURL
});
// Add a map tile layer as background.
var tileLayer = new OM.layer.TileLayer(
"baseMap",
{
dataSource:"mvdemo",
tileLayer:"demo_map",
tileServerURL:baseURL+"/mcserver"
});
mapview.addLayer(tileLayer);
// Set the initial map center and zoom level
var mapCenterLon = -122.45;
var mapCenterLat = 37.7706;
var mapZoom = 4;
var mpoint = new OM.geometry.Point(mapCenterLon,mapCenterLat,8307);
mapview.setMapCenter(mpoint);
mapview.setMapZoomLevel(mapZoom);
// Add a theme-based FOI layer to display customers on the map
customersLayer = new OM.layer.VectorLayer("customers",
{
def:
{
type:OM.layer.VectorLayer.TYPE_PREDEFINED,
dataSource:"mvdemo", theme:"customers",
url: baseURL,
loadOnDemand: false
}
});
mapview.addLayer(customersLayer);
// Add a navigation panel on the right side of the map
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Using Google Maps and Bing Maps
var navigationPanelBar = new OM.control.NavigationPanelBar();
navigationPanelBar.setStyle(
{backgroundColor:"#FFFFFF",buttonColor:"#008000",size:12});
mapview.addMapDecoration(navigationPanelBar);
// Add a scale bar
var mapScaleBar = new OM.control.ScaleBar();
mapview.addMapDecoration(mapScaleBar);
// Display the map.
// The initialization and display is done just once.
mapview.init();
}
•
Additional HTML elements and JavaScript code that implement other applicationspecific user interface and control logic. For example, the HTML <input> element
and JavaScript function setLayerVisible together implement a layer visibility
control. The setLayerVisible function is coded as follows:
function setLayerVisible(checkBox)
{
// Show the customers vector layer if the check box is checked and
// hide it otherwise.
if(checkBox.checked)
customersLayer.setVisible(true) ;
else
customersLayer.setVisible(false);
}
The function is specified in the onclick attribute of the <input> element defining the
checkbox. In the following example, the function is executed whenever the user
clicks on the Show Customers check box:
<INPUT TYPE="checkbox" onclick="setLayerVisible(this)" checked/>Show Customers
4.3 Using Google Maps and Bing Maps
Applications can display Google Maps tiles or Microsoft Bing Maps tiles as a built-in
map tile layer, by creating and adding to the map window an instance of
MVGoogleTileLayer or MVBingTileLayer, respectively.
Internally, the Oracle Maps client uses the official Google Maps or Bing Maps API to
display the map that is directly served by the Google Maps or Microsoft Bing Maps
server.
•
To use the Google Maps tiles, your usage of the tiles must meet the terms of
service specified by Google (see https://developers.google.com/readme/terms).
•
To use the Bing Maps tiles, you must get a Bing Maps account. Your usage must
meet the licensing requirement specified by Microsoft (see http://
www.microsoft.com/maps/).
If you need to overlay your own spatial data on top of the Google Maps or Microsoft
Bing Maps tile layer, see also Transforming Data to a Spherical Mercator Coordinate
System.)
The following sections describe the two options for using built-in map tile layers.
•
Defining Google Maps and Bing Maps Tile Layers on the Client Side
•
Defining the Built-In Map Tile Layers on the Server Side
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4.3.1 Defining Google Maps and Bing Maps Tile Layers on the Client
Side
To define a built-in map tile layer on the client side, you need to create a
MVGoogleTileLayer or MVBingTileLayer object, and add it to the MVMapView object. (As
of Oracle Fusion Middleware Release 11.1.1.6, MVGoogleTileLayer uses the Google
Maps Version 3 API by default, and MVBingTileLayer uses the Bing Maps Version 7 API
by default.)
For example, to use Google tiles, add the Google tile layer to your map:
mapview = new MVMapView(document.getElementById("map"), baseURL);
tileLayer = new MVGoogleTileLayer() ;
mapview.addMapTileLayer(tileLayer);
In your application, you can invoke the method MVGoogleTileLayer.setMapType or
MVBingTileLayer.setMapType to set the map type to be one of the types supported by
the map providers, such as road, satellite, or hybrid.
For usage examples and more information, see the JavaScript API documentation for
MVGoogleTileLayer and MVBingTileLayer, and the tutorial demos Built-in Google Maps
Tile Layer and Built-in Bing Maps Tile Layer.
4.3.2 Defining the Built-In Map Tile Layers on the Server Side
You can define a built=-in map tile layer on the server side and use it as a regular map
visualization component tile layer on the client side. To define a built-in map tile layer
on the server side, follow these steps:
1.
Log into the map visualization component administration page (explained in
Logging in to the Map Visualization Component Administration Page).
2.
Select the Manage Map Tile Layers tab and click Create.
3.
When you are asked to select the type of map source, choose Google Maps or
Bing Maps and click Continue.
4.
Select the data source where the tile layer is to be defined.
5.
Set the license key that you have obtained from the map provider.
6.
Click Submit to create the tile layer.
After you have created the built-in map tile layer on the server side, you can use it like
any other tile layer served by MapViewer. You do not need to add any <script> tag to
load the external JavaScript library.
The following example shows a Bing Maps tile layer defined on the server side:
mapview = new MVMapView(document.getElementById("map"), baseURL);
// The Bing tile layer is defined in data source "mvdemo".
tileLayer = new MVMapTileLayer("mvdemo.BING_MAP") ;
mapview.addMapTileLayer(tileLayer);
In your application, you can invoke the method MVMapTileLayer.setMapType to set the
map type to be one of the types supported by the map providers, such as road,
satellite, or hybrid.
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Transforming Data to a Spherical Mercator Coordinate System
4.4 Transforming Data to a Spherical Mercator Coordinate
System
Popular online map services such as Google Maps and Microsoft Bing Maps use a
spherical Mercator projection for their maps.
If you are using an Oracle Database release earlier than 11.1.0.7, and if you need to
overlay your own spatial data on top of such a tile layer, such as a Google Maps or
Microsoft Bing Maps tile layer, you must set up the database to properly handle
coordinate system transformation between the coordinate system of that tile layer and
your own data coordinate system, if the two coordinate systems are not the same.
Note:
To perform the actions in this section, your database must be Release
10.2.0.1 or later.
Google Maps uses a Spherical Mercator coordinate system (EPSG: 3785), which is
also widely used among commercial API providers such as Yahoo! Maps and
Microsoft Bing Maps. This coordinate system (SRID 3785) was not provided with
Oracle Spatial and Graph before Release 11.1.0.7. In order to enable the map
visualization componentthe map visualization component and Oracle Spatial and
Graph to transform your own data to this coordinate system, you must first add this
coordinate system definition into your Oracle database if it is not already defined.
To check if this coordinate system is defined, you can enter the following statement:
SELECT srid FROM mdsys.cs_srs WHERE srid=3785;
If the preceding statement returns a row, you do not need to perform the actions in this
section. If the preceding statement does not return a row, you must perform the
actions in this section in order to be able to overlay your own spatial data on top of the
tile layer.
Follow these steps:
1.
Connect to the database as a privileged user, such as one with the DBA role.
2.
Run the csdefinition.sql script, as follows. (Replace $MAPVIEWER_HOME with the root
directory of the WebLogic Server instance where your MapViewer is deployed,
and enter the command on a single line.)
•
Linux: $MAPVIEWER_HOME/j2ee/home/applications/mapviewer/web/WEB-INF/admin/
csdefinition.sql
•
Windows: $MAPVIEWER_HOME\j2ee\home\applications\mapviewer\web\WEB-INF
\admin\csdefinition.sql
3.
If necessary, create a transformation rule to cause Oracle Spatial and Graph to
skip datum conversion when transforming data from a specified coordinate system
to the Spherical Mercator system. To find out if you need to create such a
transformation rule, see Creating a Transformation Rule to Skip Datum
Conversion.
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4.
•
Either pre-transform your spatial data for better performance, or let the map
visualization component transform the data at runtime ("on the fly"). Note that if
your database release is earlier than 10.2.0.4, pre-transforming is the only option.
•
To pre-transform all your data into the Spherical Mercator coordinate system,
use the SDO_CS.TRANSFORM_LAYER procedure on all the data, and use
the transformed data for mapping. (See the SDO_CS.TRANSFORM_LAYER
reference section in Oracle Spatial and Graph Developer's Guide.)
•
To let the map visualization component transform the data at runtime, do not
transform the data before using it for mapping.
Creating a Transformation Rule to Skip Datum Conversion
4.4.1 Creating a Transformation Rule to Skip Datum Conversion
Spatial data is often in a coordinate system based on an ellipsoid datum, such as
WGS84 or BNG. In such cases, Oracle Spatial and Graph by default applies datum
conversion when transforming the data into the Spherical Mercator system. This will
introduce a small amount of mismatch or error between your data and the Google
Maps other map service tiles. If you want to address this issue, you can create
transformation rules that tell Oracle Spatial and Graph to skip datum conversion when
transforming data from a specified coordinate system to the Spherical Mercator
system.
Example 4-1 shows SQL statements that are included in the csdefinition.sql script
and that create such transformations rules. However, if the coordinate system of your
spatial data is not covered by the rules shown in Example 4-1, you can create your
own rule if the coordinate system of your data is not covered by these rules. (For more
information about creating coordinate system transformation rules, see Oracle Spatial
and Graph Developer's Guide.)
Example 4-1
-----
Transformation Rules Defined in the csdefinition.sql Script
Create the tfm_plans, that is, the transformation rules.
Note: This will result in an incorrect conversion since it ignores a datum
datum between the ellipsoid and the sphere. However, the data will match
up better on Google Maps.
-- For wgs84 (8307)
call sdo_cs.create_pref_concatenated_op( 83073785, 'CONCATENATED OPERATION 8307
3785', TFM_PLAN(SDO_TFM_CHAIN(8307, 1000000000, 4055, 19847, 3785)), NULL);
-- For 4326, EPSG equivalent of 8307
call sdo_cs.create_pref_concatenated_op( 43263785,
'CONCATENATED_OPERATION_4326_3785', TFM_PLAN(SDO_TFM_CHAIN(4326, 1000000000, 4055,
19847, 3785)), NULL);
-- For OS BNG, Oracle SRID 81989
call sdo_cs.create_pref_concatenated_op( 819893785, 'CONCATENATED OPERATION 81989
3785', TFM_PLAN(SDO_TFM_CHAIN(81989, -19916, 2000021, 1000000000, 4055, 19847,
3785)), NULL);
-- For 27700, EPSG equivalent of 81989
call sdo_cs.create_pref_concatenated_op( 277003785,
'CONCATENATED_OPERATION_27700_3785', TFM_PLAN(SDO_TFM_CHAIN(27700, -19916, 4277,
1000000000, 4055, 19847, 3785)), NULL);
commit;
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Using Dynamic Tile Layers
4.5 Using Dynamic Tile Layers
A dynamic tile layer is a tile layer defined on the client side.
A dynamic tile layer differs from a regular tile layer in the following ways:
•
It is defined by the client application, so it does not need to be predefined in the
USER_SDO_CACHED_MAPS metadata.
•
The server does not cache the map tiles.
•
It can use third party maps services, when a map tile image URL generation
function is provided.
Thus, a dynamic tile layer can be defined dynamically by a client application, and the
map images may come from a map visualization component server or from a third
party map service.
•
Creating a Universe and Configuration Instance for a Dynamic Tile Layer
•
Creating a Dynamic Tile Layer Using a Base Map
•
Creating a Dynamic Tile Layer Using Predefined Themes
•
Creating a Dynamic Tile Layer Using Spatial Tables Directly
•
Creating a Dynamic Tile Layer Using Third Party Map Services
•
Dynamic Tile Layer Use Case
4.5.1 Creating a Universe and Configuration Instance for a Dynamic
Tile Layer
Before creating a dynamic tile layer instance, you must create a universe and a tile
layer configuration for a dynamic tile layer.
For example, assume that a variable named baseURL is properly defined (such as
http://myapp.mycorp.com/mapviewer) and that the specified data source exists. You
must create a tile layer configuration instance and a universe instance. You can use
an Oracle Maps JavaScript API built-in universe or create your own. For simplicity, a
built-in universe is used here.
A tile layer configuration instance only needs to define the dimension of an image tile,
and 256 pixels for a tile image's width and height are commonly used. The following
code snippet creates this instance:
var myuniv= new OM.universe.LatLonUniverse(); // a built-in universe
var myconfig=new OM.layer.TileLayerConfig( // a tile layer configure instance
{
tileImageWidth: 256,
tileImageHeight: 256
});
4.5.2 Creating a Dynamic Tile Layer Using a Base Map
Creating a dynamic tile layer using a base map is the simplest approach, because the
map contents are already defined by a server-side map visualization component base
map. Follow these steps.
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1.
Create a ServerMapRequest instance and set its properties. For example:
var req = new OM.server.ServerMapRequest(baseURL);
req.setProperties({
dataSource:"MVDEMO",
basemap: 'demo_map', // this basemap property defines the map
contents
transparent:true,
antialiase:"false"
});
2.
Create an object containing properties of this dynamic tile layer. For example:
var dtl_props = {
universe: myuniv,
tileLayerConfig: myconfig,
tileServerURL: baseURL + "/omserver", // map images come from this
omserver
enableUTFGrid: true, // the UTFGrid is enabled
enableUTFGridInfoWindow: true, // the info window for displaying
UTFGrid is enabled
utfGridResolution: 4 // one grid cell represents 16 (4 by 4) image
pixels
};
In this example, the string value in variable tileServerURL is pointing to a map
visualization component server. It could be the same server as where the web
application is deployed, or another map visualization component server instance.
For example, it can be in either of the following forms:
•
From the same Oracle Maps server instance:. For example:
var baseURL=document.location.protocol+"//"+document.location.host+"/
mapviewer";
•
From another Oracle Maps server instance. For example:
var baseURL="http://myapp.mycorp.com/mapviewer ";
3.
Create a dynamic tile layer. For example:
var dynamic_tilelayer_1 = new OM.layer.DynamicTileLayer("dtl1", dtl_props,
req);
The dynamic tile layer requests map images from the map visualization
component's map server (omserver), which renders a fresh map image and does
not cache the images on disk.
From the preceding examples, notice that three statements are given to create a
dynamic tile layer: (1) create a map request instance (ServerMapRequest); (2) create an
object containing the dynamic tile layer related properties; and (3) instantiate a
dynamic tile layer.
The dynamic tile layer requests map images from the map visualization component's
map server (omserver), which renders a fresh map image and does not cache the
images on disk.
4.5.3 Creating a Dynamic Tile Layer Using Predefined Themes
Another approach to creating a dynamic tile layer is to use predefined themes. Follow
these steps.
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1.
Create a ServerMapRequest instance and set its properties. For example:
var req = new OM.server.ServerMapRequest(baseURL);
req.setProperties({
dataSource:"MVDEMO",
transparent:true,
antialiase:"false",
});
// the three themes below are defined in the metadata already.
var t1 = new OM.server.ServerPredefinedTheme("THEME_DEMO_STATES");
var t2 = new OM.server.ServerPredefinedTheme("THEME_DEMO_HIGHWAYS");
var t3 = new OM.server.ServerPredefinedTheme("THEME_DEMO_CITIES");
req.addThemes([t1, t2, t3]);
2.
Create an object containing properties of this dynamic tile layer. For example:
var dtl_props = {
universe: myuniv,
tileLayerConfig: myconfig,
tileServerURL: baseURL + "/omserver",
enableUTFGrid: true,
enableUTFGridInfoWindow: true,
utfGridResolution: 4
};
3.
Create a dynamic tile layer. For example:
var dynamic_tilelayer_2 = new OM.layer.DynamicTileLayer("dtl2", dtl_props,
req);
The dynamic tile layer requests map images from the map visualization
component's map server (omserver), which renders a fresh map image and does
not cache the images on disk.
Instead of specifying a server base map, in this approach the ServerMapRequest
instance adds some map visualization component server predefined themes. From a
practical perspective, this allows the client-side application to create tile layers using
the server-side defined themes in the view USER_SDO_THEMES.
4.5.4 Creating a Dynamic Tile Layer Using Spatial Tables Directly
You can directly use spatial tables for a dynamic tile layer by creating ServerJBCTheme
instances and adding them into a ServerMapRequest instance. Follow these steps.
1.
Create a style. For example:
var myc1 = new OM.style.Color({
styleName: "mycolor1",
stroke: "#333333",
strokeOpacity: 1.0,
fill: "#F2EFE9",
fillOpacity: 1.0
});
2.
Create a JDBC theme and set its properties. Spatial tables are used in a SQL
query statement. The statement, as a string type variable, is set as an attribute in
the OM.server.ServerJDBCTheme instance. For example:
var jdbcTStates= new OM.server.ServerJDBCTheme('theme_jdbc_states');
jdbcTStates.setDataSourceName('mvdemo');
jdbcTStates.setSRID('8307');
jdbcTStates.setGeometryColumnName('geom');
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var sql='select totpop, poppsqmi, state, state_abrv, geom from
states'; // the query
jdbcTStates.setQuery(sql); // set the SQL string
jdbcTStates.addInfoColumn({column: 'state_abrv', name:'State'});
jdbcTStates.addInfoColumn({column: 'totpop', name:'Population'});
jdbcTStates.addInfoColumn({column: 'poppsqmi', name:'Pop. Density'});
jdbcTStates.setRenderingStyleName('mycolor1');
3.
Create a ServerMapRequest instance and set its properties. For example:
var req = new OM.server.ServerMapRequest(baseURL);
req.setProperties({
dataSource:"MVDEMO",
transparent:true,
antialiase:"false",
});
req.addTheme(jdbcTStates);
req.addStyle(myc1);
4.
Create an object containing properties of this dynamic tile layer. For example:
var dtl_props = {
universe: myuniv,
tileLayerConfig: myconfig,
tileServerURL: baseURL + "/omserver",
enableUTFGrid: true,
enableUTFGridInfoWindow: true,
utfGridResolution: 4
};
5.
Create a dynamic tile layer. For example:
var dynamic_tilelayer_3 = new OM.layer.DynamicTileLayer("dtl3", dtl_props,
req);
In this example, a dynamically defined style and a ServerJDBCTheme object are created
first. The ServerJDBCTheme can make use the spatial tables directly using a SQL
statement. The tables are then used by the addTheme and addStyle methods of a
ServerMapRequest object.
4.5.5 Creating a Dynamic Tile Layer Using Third Party Map Services
Another approach to create a dynamic tile layer is to use third party map services. The
map service URL of a third party is provided by a client provided URL generation
function. Follow these steps.
1.
Using the third party map service provider's specifications, create a URL
construction function for building map image requests by a dynamic tile layer. For
example:
var urlb = function (w, h, minX, minY, maxX, maxY, options){
var str="http://my.mycorp.com:8080/geoserver/ows?";
var optParams="";
str = str+"request=getmap"+
"&bbox="+minX+","+minY+","+maxX+","+maxY+
"&width="+w+
"&height="+h;
if (!OM.isNull(options)) {
for (var key in options) {
optParams=optParams +"&"+key +"="+options[key];
}
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}
return str+optParams;
}
2.
Create an object containing properties of this dynamic tile layer. For example:
var dtl_props = {
universe: myuniv,
tileLayerConfig: myconfig,
urlBuilder: urlb,
urlBuilderOptions: {
"layers": "topp:states,sf:sfdem,sf:roads,sf:streams",
"CRS":
"CRS:84",
"service": "WMS",
"version": "1.3.0",
"format": "image/png"
}
};
3.
Create a dynamic tile layer. For example:
var dynamic_tilelayer_4 = new OM.layer.DynamicTileLayer("dl4", dtl_props);
In this example, a dynamic tile layer instance (dynamic_tilelayer_4) contains a
urlBuilder property to provide a URL generation function (iurlb). The URL generation
function will be used by the dynamic tile layer for fetching image tiles from the
specified map service provider. This example uses a third party map provider, a
GeoServer instance, to provide map images.
Additional map service provider required parameters can be provided in the
urlBuilderOptions property. This example specifies several additional parameters
(layers, CRS, service, version, and format) needed by the GeoServer instance.
4.5.6 Dynamic Tile Layer Use Case
This topic describes a dynamic tile layer use case.
The code examples come from a dynamic tile layer application. The application uses
the map visualization component server to provide map image tiles. It uses spatial
tables directly via an OM.server.ServerJDBCTheme instance.
1.
Obtain the SQL query's "where" clause from an application's user interface using
the getWhereClauseFromUI() function, assuming that this function is properly defined
already in that application and returns expected results. For example:
var wherec = getWhereClauseFromUI();
2.
Create a JDBC theme and set its properties. For example:
var objJDBCTheme= new OM.server.ServerJDBCTheme();
objJDBCTheme.setDataSourceName('storm');
objJDBCTheme.setSRID('3857');
objJDBCTheme.setXColumnName('long_loc');
objJDBCTheme.setYColumnName('lat_loc');
objJDBCTheme.addInfoColumn({column:
objJDBCTheme.addInfoColumn({column:
objJDBCTheme.addInfoColumn({column:
objJDBCTheme.addInfoColumn({column:
objJDBCTheme.addInfoColumn({column:
objJDBCTheme.addInfoColumn({column:
objJDBCTheme.addInfoColumn({column:
'YEAR', name:'Year'});
'MONTH', name:'Month'});
'DAY', name:'Day'});
'STATE', name:'State'});
'LOSS', name:'Loss'});
'CROPLOSS', name:'Crop_loss'});
'FATALITIES', name:'Fatalities'});
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Using Dynamic Tile Layers
objJDBCTheme.addInfoColumn({column: 'INJURIES', name:'Injuries'});
objJDBCTheme.setName('theme_tornado');
objJDBCTheme.setQuery("SELECT s.geom.sdo_point.x long_loc,s.geom.sdo_point.y
lat_loc,year,month,day,state,fatalities,injuries,loss,croploss from tornado_3857
s"+
(wherec === "" ?"": wherec));
objJDBCTheme.setRenderingStyleName('V.TORNADO');
3.
Create a ServerMapRequest instance and set its properties. For example:
var req = new OM.server.ServerMapRequest(baseURL);
req.setProperties({
dataSource:'storm',
transparent:true, // map image is set to be transparent
antialiase:"false"
});
req.addTheme(objJDBCTheme);
4.
Create an object containing properties of this dynamic tile layer. For example:
var dtl_props = {
universe: myuniv,
tileLayerConfig: myconfig,
tileServerURL: baseURL + "/omserver",
enableUTFGrid: true,
enableUTFGridInfoWindow: true,
utfGridResolution: 4
};
5.
Create a dynamic tile layer. For example:
var tornado_damage = new OM.layer.DynamicTileLayer("tornado_damage",
dtl_props, req);
The code examples in the preceding steps illustrate the following:
•
The map application fetches map images from a map visualization component
server. Therefore, it may use all available features from the map visualization
component server.
•
The map image is set to be transparent (that is, the value for property transparent
is true). This setting makes all of the non-overlapping features visible when
multiple dynamic tile layers are stacked for display. For example, when you
overlay a tornado_damage dynamic tile layer on top of a hail_damage dynamic tile
layer, you may see both layers on the map when such events (as their names
suggest) were happening at non-overlapping locations. This setting is more useful
for multiple layers containing linear and point features. Note that since the API
allows you to turn on/off a layer's visibility, you can always make a layer of interest
stand out and be visible in your application.
•
The dynamic tile layer also enables the map visualization component server's
UTFGrid support (specifically, the value for property enableUTFGrid is set to true,
with a resolution value set to 4 for the utfGridResolution property). This setting
instructs map visualization component's API to request an additional UTFGrid file as
a companion of its map tile image. It is a JSON file, and it contains a twodimensional grid table in UTF encoding, that matches the tile image. It also
contains some text attributes for each grid cell.
When a mouse event (for example, a mouse click) is triggered at an image pixel,
its corresponding grid cell can then be located, its UTF code be obtained, and
4-16
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Using Dynamic Tile Layers
subsequently, the text attributes associated with that grid cell's UTF code can be
retrieved and displayed in a popup info window.
The text attributes contained in that JSON file are specified using the
addInfoColumn() method. Those text attributes will be displayed in an info window
for a pixel being clicked on the map.
Note that if server-side predefined geometry themes are used by a dynamic tile
layer, the text attributes for an info window must have been specified in theme's
<hidden_info> element. This also applies for the base map-based dynamic tile
layers, where the predefined themes are found in the map visualization
component's base map definition
A resolution value (for example, "utfGridResolution":4) indicates the width and
height of the grid cell compares with its companion map tile image pixel. In this
example, one grid cell in the UTFGrid data set represents 16 pixels (4x4=16).
•
This dynamic tile layer makes use of spatial table directly via a ServerJDBCTheme to
define its map contents. In its embedded SQL statement, the client web
application has the flexibility to construct the whole statement, including the tables
to use, the columns to select, and the "where" clause to refine the query. In the
code snippets, it assumes that a client function, getWhereClauseFromUI(), only
constructs the 'where' clause in the JDBC theme definition.
The dynamic tile layer supported in the Oracle Maps JavaScript API allows the map
visualization component server metadata to be used by the tile layer, and it offers
flexibility in how a dynamic tile layer is defined and where to fetch its map images by
the client application.
4-17
5
Oracle Map Builder Tool
This chapter briefly describes the map visualization component Map Builder tool, also
referred to as Oracle Map Builder. It does not provide detailed information about the
tool's interface; for that you should use see online help available when you use Oracle
Map Builder.
Oracle Map Builder is a standalone application that lets you create and manage the
mapping metadata (about styles, themes, and base maps) that is stored in the
database. For example, use this tool to create a style or to modify the definition of a
style. Besides handling the metadata, the tool provides interfaces to preview the
metadata (for example, to see how a line style will appear on a map) and also spatial
information.
Whenever possible, you should use Oracle Map Builder instead of directly modifying
map visualization component metadata views to create, modify, and delete information
about styles, themes, and maps. For any modifications made outside Oracle Map
Builder, such as with SQL statements, you should refresh the database connection in
Oracle Map Builder to get the current items.
To use Oracle Map Builder effectively, you must understand the map visualization
component concepts explained in Map Visualization Concepts and the information
about map requests in Map Visualization Servers.
Topics:
•
Running Oracle Map Builder
Oracle Map Builder is shipped as a JAR file (mapbuilder.jar).
•
Oracle Map Builder User Interface
Oracle Map Builder generally uses the left side for navigation to find and select
objects, and the right side to display information about selected objects.
5.1 Running Oracle Map Builder
Oracle Map Builder is shipped as a JAR file (mapbuilder.jar).
You can run it as a standalone Java application in a Java Development Kit (J2SE
SDK) 1.5 or later environment, as follows:
% java –jar mapbuilder.jar [Options]
Options:
-cache <cache_size> specifies the size of the in-memory geometry cache. Example: cache 64M
-config <config-file> specifies the location of the file containing Map Builder
configuration and preference information. If you do not specify this option, Map Builder
looks for a file named oasmapbuilder.xml in your home Java directory. For more
information about the configuration and preference file, see Configuring the Map
Visualization Component.
5-1
Chapter 5
Oracle Map Builder User Interface
-connect causes Map Builder at startup to register connections for all data sources
specified in the oasmapbuilder.xml preferences file or the file specified with the -config
option, and it automatically connects to the first available data source. This option
increases the application startup time. If this option is not defined, startup is faster, but
you must then use the File menu or an icon to connect to any data sources that you
want to use (see Oracle Map Builder User Interface).
-help displays information about the available options.
•
Java Libraries for Theme Creation with GDAL and Teradata
5.1.1 Java Libraries for Theme Creation with GDAL and Teradata
To create themes in Map Builder with GDAL-OGR (version 1.8 or later) or Teradata
(version 13 or later), Map Builder must be started with GDAL-OGR (gdal.jar) and/or
Teradata (terajdbc4.jar and tdgssconfig.jar) jar files on the class path. These Java
libraries can be found in the GDAL installation on your system and on the Teradata
website. (For GDAL, see the GDAL website for more information.)
The following example commands start Map Builder with additional libraries in the
class path.
Windows: java -Xmx512M -cp .\mapbuilder.jar;.\gdal.jar;.\terajdbc4.jar;.
\tdgssconfig.jar oracle.mapviewer.builder.MapBuilder
Linux: java -Xmx512M -cp ./mapbuilder.jar:./gdal.jar:./terajdbc4.jar:./
tdgssconfig.jar oracle.mapviewer.builder.MapBuilder
5.2 Oracle Map Builder User Interface
Oracle Map Builder generally uses the left side for navigation to find and select
objects, and the right side to display information about selected objects.
Figure 5-1 shows the main window of Oracle Map Builder, with the metadata
navigation tree on the left and a detail pane for a selected area style on the right.
5-2
Chapter 5
Oracle Map Builder User Interface
Figure 5-1
Oracle Map Builder Main Window
The menus at the top contain standard entries, plus entries for features specific to
Oracle Map Builder.
You can use shortcut keys to access menus and menu items: for example Alt+F for
the File menu and Alt+E for the Edit menu; or Alt+H, then Alt+A for Help, then About.
Icons under the menus perform the following actions:
•
Add new connection creates a new database connection for Oracle Map Builder
to use.
•
Load/Add/Remove connection loads or adds database connection for Oracle
Map Builder to use, or removes a database connection from the available
connections that Oracle Map Builder can use.
•
Create new metadata creates a new base map, theme, or style.
•
Open opens a base map, theme, or style.
5-3
Chapter 5
Oracle Map Builder User Interface
•
Save saves any changes to the currently selected object.
•
Save All saves any changes to all open objects.
The left side of the Oracle Map Builder window has the Metadata navigator, including
a database connection selector, icons for performing actions, and a hierarchical tree
display for the map visualization component metadata objects (categorized by object
type) accessible to the currently selected database connection. To select an object,
expand the appropriate tree node or nodes, then double-click the object.
The right side of the Oracle Map Builder window has tabs and panes for detail views of
objects that you select or open
To switch among objects, click the desired tabs; to close a tab, click the X in the tab. If
you make changes to an object and click the X, you are asked if you want to save the
changes.
The Messages area is used for feedback information as appropriate (for example,
results of an action, or error or warning messages).
Detailed help is available within the Oracle Map Builder interface. See the online help
for more information about Oracle Map Builder, including information about specific
panes and dialog boxes.
5-4
A
XML Format for Styles, Themes, Base
Maps, and Map Tile Layers
This appendix describes the XML format for defining style, themes, and base maps
using the map visualization component metadata views.
These metadata views are described in Map Visualizer Metadata Views.
The metadata views for map visualization component styles (USER_SDO_STYLES
and related views) contain a column named DEFINITION. For each style, the
DEFINITION column contains an XML document that defines the style to the rendering
engine.
Each style is defined using a syntax that is similar to SVG (scalable vector graphics).
In the map visualization component syntax, each style's XML document must contain a
single <g> element, which must have a class attribute that indicates the type or class of
the style. For example, the following defines a color style with a filling color
component:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<desc> red </desc>
<g class="color" style="fill:#ff1100"/>
</svg>
The map visualization component XML parser looks only for the <g> element in a style
definition; other attributes such as the <desc> element are merely informational and are
ignored.
Note:
You can make the size of a style scalable by specifying a unit other than the
default pixel (px) -- for example, width:15.0km or stroke-width:10.0m. For
information about using scalable styles, see Scaling the Size of a Style
(Scalable Styles).
The metadata views for map visualization component themes (USER_SDO_THEMES
and related views) contain a column named STYLING_RULES. For each theme in
these views, the STYLING_RULES column contains an XML document (a CLOB
value) that defines the styling rules of the theme.
The metadata views for MapViewer base maps (USER_SDO_MAPS and related
views) contain a column named DEFINITION. For each base map in these views, the
DEFINITION column contains an XML document (a CLOB value) that defines the base
map.
The following sections describe the XML syntax for each type of mapping metadata.
A-1
Appendix A
Color Styles
•
Color Styles
A color style has a fill color, a stroke color, or both.
•
Marker Styles
A marker style represents a marker to be placed on point features or on label
points of area and linear features.
•
Line Styles
A line style is applicable only to a linear feature, such as a road, railway track, or
political boundary.
•
Area Styles
An area style defines a pattern to be used to fill an area feature.
•
Text Styles
A text style defines the font and color to be used in labeling spatial features.
•
Advanced Styles
Advanced styles are structured styles made from simple styles.
•
Themes: Styling Rules
A theme definition contains one <styling_rules> element, which may have several
other elements depending on the theme type.
•
Base Maps
A base map definition consists of one or more themes.
•
Map Tile Layers
An Oracle Maps map tile layer which assembles and displays pregenerated map
image tiles from the map tile server,
A.1 Color Styles
A color style has a fill color, a stroke color, or both.
When applied to a shape or geometry, the fill color (if present) is used to fill the interior
of the shape, and the stroke color (if present) is used to draw the boundaries of the
shape. Either color can also have an alpha value, which controls the transparency of
that color.
For color styles, the class attribute of the <g> element must be set to "color". The <g>
element must have a style attribute, which specifies the color components and their
optional alpha value. For example:
•
<g class="color" style="fill:#ff0000"> specifies a color style with only a fill color
(whose RGB value is #ff0000).
•
<g class="color" style="fill:#ff0000;stroke:blue"> specifies a color style with a
fill color and a stroke color (blue).
You can specify a color value using either a hexadecimal string (such as #00ff00) or a
color name from the following list: black, blue, cyan, darkGray, gray, green, lightGray,
magenta, orange, pink, red, white, yellow.
To specify transparency for a color style, you can specify fill-opacity and strokeopacity values from 0 (completely transparent) to 255 (opaque). The following
example specifies a fill component with half transparency:
<g class="color" style="fill:#ff00ff;fill-opacity:128">
The following example specifies both stroke and fill opacity:
A-2
Appendix A
Marker Styles
<g class="color" style= "stroke:red;stroke-opacity:70;
fill:#ff00aa;fill-opacity:129">
The syntax for the style attribute is a string composed of one or more name:value pairs
delimited by semicolons. (This basic syntax is used in other types of styles as well.)
For stroke colors, you can define a stroke width. The default stroke width when
drawing a shape boundary is 1 pixel. To change that, add a stroke-width:value pair to
the style attribute string. The following example specifies a stroke width of 3 pixels:
<g class="color" style="stroke:red;stroke-width:3">
A.2 Marker Styles
A marker style represents a marker to be placed on point features or on label points of
area and linear features.
A marker can be either a vector marker or raster image marker. A marker can also
have optional notational text. For a vector marker, the coordinates of the vector
elements must be defined in its XML document. For a marker based on a raster
image, the XML document for the style indicates that the style is based on an external
image.
The marker XML document specifies the preferred display size: the preferred width
and height are defined by the width:value;height:value pairs in the style attribute of
the <g> element. The class attribute must be set to "marker". Some markers must be
overlaid with some notational text, such as a U.S. interstate highway shield marker,
which, when rendered, must also have a route number plotted on top of it. The style
for such notational text is a style attribute with one or more of the following name-value
pairs: font-family:value, font-style:value, font-size:value, and font-weight:value.
The following example defines an image-based marker that specifies font attributes
(shown in bold) for any label text that may be drawn on top of the marker:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<desc></desc>
<g class="marker"
style="width:20;height:18;font-family:sans-serif;font-size:9pt;fill:#ffffff">
<image x="0" y="0" width="9999" height="9999" type="gif"
href="dummy.gif"/>
</g>
</svg>
In the preceding example, when the marker is applied to a point feature with a labeling
text, the label text is drawn centered on top of the marker, using the specified font
family and size, and with the fill color (white in this case) as the text foreground. The
label text (495) in Figure A-1 in Using Marker Styles on Lines has the text attributes
specified in this example.
•
Vector Marker Styles
•
Image Marker Styles
•
TrueType Font-Based Marker Styles
•
Using Marker Styles on Lines
A-3
Appendix A
Marker Styles
A.2.1 Vector Marker Styles
A vector marker can be a simple polygon, an optimized rectangle (defined using two
points), a single polyline, or a circle, but not any combination of them. For each type of
vector marker, its <g> element must contain a corresponding subelement that specifies
the geometric information (coordinates for the polygon, optimized rectangle, or
polyline, or radius for the circle):
•
A polygon definition uses a <polygon> element with a points attribute that specifies
a list of comma-delimited coordinates. For example:
<g class="marker">
<polygon points="100,20,40,50,60,80,100,20"/>
</g>
•
An optimized rectangle definition uses a <rect> element with a points attribute that
specifies a list of comma-delimited coordinates. For example:
<g class="marker">
<rect points="0,0, 120,120"/>
</g>
•
A polyline definition uses a <polyline> element with a points attribute that specifies
a list of comma-delimited coordinates. For example:
<g class="marker">
<polyline points="100,20,40,50,60,80"/>
</g>
•
A circle definition uses a <circle> element with an r attribute that specifies the
radius of the circle. For example:
<g class="marker">
<circle r="50"/>
</g>
You can specify a stroke or fill color, or both, for any vector-based marker. The syntax
is the same as for the style attribute for a color style. The following example defines a
triangle marker that has a black border and that is filled with a half-transparent yellow:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="marker" style="stroke:#000000;fill:#ffff00;fill-opacity:128">
<polygon points="201.0,200.0, 0.0,200.0, 101.0,0.0"/>
</g>
</svg>
If a marker is scalable, you can set the marker's maximum size in pixels on a map by
using the max_size_in_px attribute. Setting this attribute to an appropriate value will
prevent the marker from getting so large as to block other map features when the user
zooms in to view fine map details. The following example sets the marker's maximum
size to 64 pixels:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="marker" max_size_in_px="64" style="stroke:#0000BB;fill:#0033FF;width:
3.0mile;height:3.0mile;font-family:Dialog;font-size:12;font-fill:#FF0000">
<polygon points="0.0,0.0,0.0,100.0,100.0,100.0,100.0,0.0,0.0,0.0"/>
</g>
</svg>
A-4
Appendix A
Marker Styles
A.2.2 Image Marker Styles
For an image marker, its XML document contains an <image> element that identifies
the marker as based on an image. The image must be in GIF format, and is stored in
the IMAGE column in the styles metadata views.
The following example is an XML document for an image marker:
<?xml version="1.0" standalone="yes"?>
<svg>
<g class="marker"
style="width:20;height:18;font-family:sansserif;font-size:9pt">
<image x="0" y="0" width="9999" height="9999" type="gif" href="dummy.gif"/>
</g>
</svg>
Note that in the preceding example, it would be acceptable to leave the <image>
element empty (that is, <image/>) to create a valid definition with the image to be
specified later.
A.2.3 TrueType Font-Based Marker Styles
For a TrueType font-based marker, its marker symbol is stored in a TrueType font file,
which has the .ttf file extension and which typically contains many individual symbols
or glyphs. Many GIS software packages come with TrueType font files that contain
symbols useful for mapping.
Before the map visualization component can use a symbol in a TrueType font file, you
must do the following:
1.
Import the TrueType font file into the database, preferably by using the Map
Builder tool (described in Oracle Map Builder Tool), which causes the symbols in
the font file to be inserted into a single row in the system view
USER_SDO_STYLES. In this new row, the TYPE column contains the string TTF,
and the IMAGE column contains the contents of the TrueType font file. After the
import operation, you can use the Map Builder tool to view all the glyphs or
symbols contained inside the TrueType font file. Also, because the font file is now
physically stored inside a database, it can be shared by all the map visualization
component users.
2.
Create a map visualization component marker style based on a glyph or symbol
inside an imported TrueType font, preferably using the Map Builder tool.
The following example shows the use of a TrueType font-based marker (with
TrueType-specific material in bold):
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="marker" style="fill:#ff0000;width:25;height:25">
<ttfSymbol fontName="ERS_INCIDENTS" charCode="118" />
</g>
</svg>
A.2.4 Using Marker Styles on Lines
Marker styles are usually applied to point features, in which case the marker style is
rendered on the point location that represents the feature. However, with line (line
A-5
Appendix A
Line Styles
string) features such as highways, the marker must be placed at some point along the
line to denote some information about the feature, such as its route number. For
example, on maps in the United States, a shield symbol is often placed on top of a
highway, with a route number inside the symbol, as shown with Route 495 in
Figure A-1.
Figure A-1
Shield Symbol Marker for a Highway
To achieve the result shown in Figure A-1, you must do the following:
1.
Choose a marker style, and add a text style definition (font family, font size, fill
color, and so on), as shown in the example in Marker Styles.
2.
Specify the marker style as the labeling style in the styling rules for the theme. The
following example shows the XML document with the styling rules for a theme to
show highways. A marker style (shown in bold in the example) is specified. The
label text (495 in Figure A-1) is a value from the label column, which is named
LABEL in this example.
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="political">
<rule>
<features style="L.PH"> (name_class = 'I' and TOLL=0) </features>
<label column="label" style="M.SHIELD1">1</label>
</rule>
<styling_rules>
The map visualization component automatically determines the optimal position on the
line for placement of the marker style (the shield in this example).
A.3 Line Styles
A line style is applicable only to a linear feature, such as a road, railway track, or
political boundary.
In other words, line styles can be applied only to Oracle Spatial and Graph geometries
with an SDO_GTYPE value ending in 2 (line) or 6 (multiline). (For information about
the SDO_GEOMETRY object type and SDO_GTYPE values, see Oracle Spatial and
Graph Developer's Guide.)
When the map visualization component draws a linear feature, a line style tells the
rendering engine the color, dash pattern, and stroke width to use. A line style can have
a base line element which, if defined, coincides with the original linear geometry. It can
also define two edges parallel to the base line. Parallel line elements can have their
own color, dash pattern, and stroke width. If parallel lines are used, they must be
located to each side of the base line, with equal offsets to it.
A-6
Appendix A
Line Styles
To draw railroad-like lines, you need to define a third type of line element in a line style
called hashmark. For a <line> element of class hashmark, the first value in the dash
array indicates the gap between two hash marks, and the second value indicates the
length of the hash mark to either side of the line. The following example defines a hash
mark line with a gap of 8.5 screen units and a length of 3 screen units at each side of
the base line:
<line class="hashmark" style="fill:#003333" dash="8.5,3.0"/>
The following example defines a complete line style.
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="line" style="fill:#ffff00;stroke-width:5">
<line class="parallel" style="fill:#ff0000;stroke-width:1.0"/>
<line class="base" style="fill:black;stroke-width:1.0" dash="10.0,4.0"/>
</g>
</svg>
In the preceding example, class="line" identifies the style as a line style. The overall
fill color (#ffff00) is used to fill any space between the parallel lines and the base line.
The overall line width (5 pixels) limits the maximum width that the style can occupy
(including that of the parallel lines).
The line style in the preceding example has both base line and parallel line elements.
The parallel line element (class="parallel") is defined by the first <line> element,
which defines its color and width. (Because the definition does not provide a dash
pattern, the parallel lines or edges will be solid.) The base line element (class="base")
is defined by the second <line> element, which defines its color, width, and dash
pattern.
A marker (such as a direction marker) can be defined for a line style. The marker-name
parameter specifies the name of a marker style, the marker-position parameter
specifies the proportion (from 0 to 1) of the distance along the line from the start point
at which to place the marker, and the marker-size parameter specifies the number of
display units for the marker size. The marker orientation follows the orientation of the
line segment on which the marker is placed.
The following example defines a line style with direction marker:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="line" style="fill:#33a9ff;stroke-width:4;
marker-name:M.IMAGE105_BW;marker-position:0.15;marker-size=8">
<line class="parallel" style="fill:red;stroke-width:1.0"/>
</g>
</svg>
To get multiple markers, add the multiple-marker attribute to the style definition. In this
case the marker-position will define the position for the first marker and the space in
between markers. The following example defines a line style with a direction marker
that starts at position 0.15 and that is repeated continually with a space of 0.15
between each occurrence.
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="line" style="fill:#33a9ff;stroke-width:4;
marker-name:M.IMAGE105_BW; marker-position:0.15;
marker-size=8; multiple-marker=true">
<line class="parallel" style="fill:red;stroke-width:1.0"/>
A-7
Appendix A
Area Styles
</g>
</svg>
A.4 Area Styles
An area style defines a pattern to be used to fill an area feature.
In the current release, area styles must be image-based. That is, when you apply an
area style to a geometry, the image defining the style is plotted repeatedly until the
geometry is completely filled.
The definition of an area style is similar to that of an image marker style, which is
described in Image Marker Styles.
The following example defines an area style:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="area" style="stroke:#000000">
<image/>
</g>
</svg>
In the preceding example, class="area" identifies the style as an area style. The stroke
color (style="stroke:#000000") is the color used to draw the geometry boundary. If no
stroke color is defined, the geometry has no visible boundary, although its interior is
filled with the pattern image.
You can also specify any line style to be used as the boundary for an area style. The
following area style definition uses the line-style keyword (shown in bold in the
example) to specify a line style to be used for the borders of features:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="area" style="line-style:L.DPH">
<image x="0" y="0" width="9999" height="9999" type="gif" href="dummy.gif"/>
</g>
</svg>
As with the image marker style, the image for an area style must be stored in a
separate column (identified in the IMAGE column in the USER_SDO_STYLES and
ALL_SDO_STYLES metadata views, which are described in xxx_SDO_STYLES
Views).
A.5 Text Styles
A text style defines the font and color to be used in labeling spatial features.
The class attribute must have the value "text". For the font, you can specify its style
(plain, italic, and so on), font family, size, and weight. To specify the foreground color,
you use the fill attribute.
The following example defines a text style:
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<g class="text" style="font-style:plain; font-family:Dialog; font-size:14pt;
font-weight:bold; fill:#0000ff">
Hello World!
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Appendix A
Advanced Styles
</g>
</svg>
In the preceding example, the text "Hello World!" is displayed only when the style itself
is being previewed in a style creation tool, such as the Map Builder tool. When the
style is applied to a map, it is always supplied with an actual text label that the map
visualization component obtains from a theme.
A text style can provide a floating white background around the rendered text, to make
the labels easier to read on a map that has many features. Figure A-2 shows the label
Vallejo with a white background wrapping tightly around the letters.
Figure A-2
Text Style with White Background
To achieve the result shown in Figure A-2, you must specify the float-width attribute
in the <g> element of the text style definition. The following example uses the floatwidth attribute (shown in bold in the example) to specify a white background that
extends 3.5 pixels from the boundary of each letter. (The Hello World! text is ignored
when the style is applied to the display of labels.)
<?xml version="1.0" standalone="yes"?>
<svg width="1in" height="1in">
<desc></desc>
<g class="text" float-width="3.5"
style="font-style:plain; font-family:Dialog; font-size:12pt; font-weight:bold;
fill:#000000">
Hello World!
</g>
</svg>
A.6 Advanced Styles
Advanced styles are structured styles made from simple styles.
Advanced styles are used primarily for thematic mapping. The core advanced style is
the bucket style (BucketStyle), and every advanced style is a form of bucket style. A
bucket style is a one-to-one mapping between a set of primitive styles and a set of
buckets. Each bucket contains one or more attribute values of features to be plotted.
For each feature, one of its attributes is used to determine which bucket it falls into or
is contained within, and then the style assigned to that bucket is applied to the feature.
Two special types of bucket styles are also provided: color scheme (described in Color
Scheme Styles) and variable (graduated) marker (described in Variable Marker
Styles).
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Appendix A
Advanced Styles
Other advanced styles are dot density (described in Dot Density Marker Styles), bar
chart (described in Bar Chart Marker Styles), collection (described in Collection
Styles), and variable pie chart (described in Variable Pie Chart Styles).
•
Bucket Styles
•
Color Scheme Styles
•
Variable Marker Styles
•
Dot Density Marker Styles
•
Bar Chart Marker Styles
•
Collection Styles
•
Variable Pie Chart Styles
•
Heat Map Styles
A.6.1 Bucket Styles
A bucket style defines a set of buckets, and assigns one primitive style to each bucket.
The content of a bucket can be either of the following:
•
A collection of discrete values (for example, a bucket for all counties with a
hurricane risk code of 1 or 2, a bucket for all counties with a hurricane risk code of
3, and so on).
•
A continuous range of values (for example, a bucket for all counties with average
family income less than $30,000, a bucket for all counties with average family
income from $30,000 through $39,999, and so on). In this case, the ranges of a
series of buckets can be individually defined (each defined by an upper-bound
value and lower-bound value) or equally divided among a master range.
The following code excerpt shows the basic format of a bucket style:
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets>
. . .
</Buckets>
</BucketStyle>
</AdvancedStyle>
In contrast with the other (primitive) styles, an advanced style always has a root
element identified by the <AdvancedStyle> tag.
For bucket styles, a <BucketStyle> element is the only child of the <AdvancedStyle>
element. Each <BucketStyle> element has one or more <Buckets> child elements,
whose contents vary depending on the type of buckets.
•
Collection-Based Buckets with Discrete Values
•
Individual Range-Based Buckets
•
Equal-Ranged Buckets
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Appendix A
Advanced Styles
A.6.1.1 Collection-Based Buckets with Discrete Values
If each bucket of a bucket style contains a collection of discrete values, use a
<CollectionBucket> element to represent each bucket. Each bucket contains one or
more values. The values for each bucket are listed as the content of the
<CollectionBucket> element, with multiple values delimited by commas. The following
example defines three buckets.
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets>
<CollectionBucket seq="0" label="commercial"
style="10015">commercial</CollectionBucket>
<CollectionBucket seq="1" label="residential"
style="10031">residential, rural</CollectionBucket>
<CollectionBucket seq="2" label="industrial"
style="10045">industrial, mining, agriculture</CollectionBucket>
</Buckets>
</BucketStyle>
</AdvancedStyle>
In the preceding example:
•
The values for each bucket are one or more strings; however, the values can also
be numbers.
•
The name of the style associated with each bucket is given.
•
The label attribute for each <CollectionBucket> element (commercial, residential,
or industrial) is used only in a label that is compiled for the advanced style.
•
The order of the <CollectionBucket> elements is significant. However, the values in
the seq (sequence) attributes are informational only; the map visualization
component determines sequence only by the order in which elements appear in a
definition.
Although not shown in this example, if you want a bucket for all other values (if any
other values are possible), you can create a <CollectionBucket> element with #DEFAULT#
as its attribute value. It should be placed after all other <CollectionBucket> elements,
so that its style will be rendered last.
To apply label styles to collection-based buckets with discrete values, see Specifying a
Label Style for a Bucket.
A.6.1.2 Individual Range-Based Buckets
If each bucket of a bucket style contains a value range that is defined by two values,
use a <RangedBucket> element to represent each bucket. Each bucket contains a range
of values. The following example defines four buckets.
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets>
<RangedBucket
<RangedBucket
<RangedBucket
<RangedBucket
high="10" style="10015"/>
low="10" high="40" style="10024"/>
low="40" high="50" style="10025"/>
low="50" style="10029"/>
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Appendix A
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</Buckets>
</BucketStyle>
</AdvancedStyle>
For individual range-based buckets, the lower-bound value is inclusive, while the
upper-bound value is exclusive (except for the range that has values greater than any
value in the other ranges; its upper-bound value is inclusive). No range is allowed to
have a range of values that overlaps values in other ranges.
For example, the second bucket in this example (low="10" high="40") will contain any
values that are exactly 10, as well as values up to but not including 40 (such as 39 and
39.99). Any values that are exactly 40 will be included in the third bucket.
As with the <CollectionBucket> element, the style associated with each <RangedBucket>
element is specified as an attribute.
To apply label styles to individual range-based buckets, see Specifying a Label Style
for a Bucket.
A.6.1.3 Equal-Ranged Buckets
If a bucket style contains a series of buckets that contain an equally divided range of a
master range, you can omit the use of <RangedBucket> elements, and instead specify in
the <Buckets> element the master upper-bound value and lower-bound value for the
overall range, the number of buckets in which to divide the range, and a list of style
names (with one for each bucket). The following example defines five buckets
(nbuckets=5) of equal range between 0 and 29:
<?xml version="1.0" ?>
<AdvancedStyle>
<BucketStyle>
<Buckets low="0" high="29" nbuckets="5"
styles="10015,10017,10019,10021,10023"/>
</BucketStyle>
</AdvancedStyle>
In the preceding example:
•
If all values are integers, the five buckets hold values in the following ranges: 0 to
5, 6 to 11, 12 to 17, 18 to 23, and 24 to 29.
•
The first bucket is associated with the style named 10015, the second bucket is
associated with the style named 10017, and so on.
The number of style names specified must be the same as the value of the nbuckets
attribute. The buckets are arranged in ascending order, and the styles are assigned in
their specified order to each bucket.
A.6.2 Color Scheme Styles
A color scheme style automatically generates individual color styles of varying
brightness for each bucket based on a base color. The brightness is equally spaced
between full brightness and total darkness. Usually, the first bucket is assigned the
brightest shade of the base color and the last bucket is assigned the darkest shade.
You can include a stroke color to be used by the color style for each bucket. The
stroke color is not part of the brightness calculation. So, for example, if a set of
polygonal features is rendered using a color scheme style, the interior of each polygon
A-12
Appendix A
Advanced Styles
is filled with the color (shade of the base color) for each corresponding bucket, but the
boundaries of all polygons are drawn using the same stroke color.
You can include an opacity value (0 to 255, for transparent to opaque) for the base
color (using the basecolor_opacity attribute) and for the stroke color (using the
strokecolor_opacity attribute).
The following example defines a color scheme style with a black stroke color and four
buckets associated with varying shades of the base color of blue.
<?xml version="1.0" ?>
<AdvancedStyle>
<ColorSchemeStyle basecolor="blue" strokecolor="black">
<Buckets>
<RangedBucket label="&lt;10" high="10"/>
<RangedBucket label="10 - 20" low="10" high="20"/>
<RangedBucket label="20 - 30" low="20" high="30"/>
<RangedBucket label="&gt;=30" low="30"/>
</Buckets>
</ColorSchemeStyle>
</AdvancedStyle>
Note:
For the following special characters, use escape sequences instead.
For <, use: &lt
For >, use: &gt;
For &, use: &amp;
A.6.3 Variable Marker Styles
A variable marker style generates a series of marker styles of varying sizes for each
bucket. You specify the number of buckets, the start (smallest) size for the marker,
and the size increment between two consecutive markers.
Variable marker styles are conceptually similar to color scheme styles in that both
base buckets on variations from a common object: with a color scheme style the
brightness of the base color varies, and with a variable marker style the size of the
marker varies.
The following example creates a variable marker style with four buckets, each
associated with different sizes (in increments of 4) of a marker (m.circle). The marker
for the first bucket has a radius of 10 display units, the marker for the second bucket
has a radius of 14 display units, and so on. This example assumes that the marker
named m.circle has already been defined.
<?xml version="1.0" ?>
<AdvancedStyle>
<VariableMarkerStyle basemarker="m.circle" startsize="10" increment="4">
<Buckets>
<RangedBucket label="&lt;10" high="10"/>
<RangedBucket label="10 - 20" low="10" high="20"/>
<RangedBucket label="20 - 30" low="20" high="30"/>
<RangedBucket label="&gt;=30" low="30"/>
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Appendix A
Advanced Styles
</Buckets>
</VariableMarkerStyle>
</AdvancedStyle>
A.6.4 Dot Density Marker Styles
A dot density advanced marker style, when applied to an area feature such as states
or counties, randomly draws a set of dots inside the area. The number of dots drawn
inside each area is determined by the count value associated with the area. When you
define a dot density style, you must specify a marker style that will be used for each of
the dots.
The following example shows the XML definition of a simple dot density style:
<?xml version="1.0" ?>
<AdvancedStyle>
<DotDensityStyle MarkerStyle="M.STAR" DotWidth="8" DotHeight="8">
</DotDensityStyle>
</AdvancedStyle>
In the preceding example, the marker style M.STAR is used for each dot, and the size
of each dot is 8 pixels wide and high.
When you use a dot density style, you should "scale" the count value to a proper
range. For example, if you want to apply a dot density style based on the population
count for each county, you would not want to use the population count directly (one dot
for each person), because this will result in an unacceptable number of drawn dots (for
example, if a county has 15,000 people). Instead, supply a scaled down value or
expression, such as population/1000, when you define the styling rules for the theme.
(The map visualization component does not perform any scaling-down internally, so
you must do it at the SQL query level.)
A.6.5 Bar Chart Marker Styles
A bar chart advanced marker style is similar to a pie chart style, except that it draws a
bar graph for each feature to which it is applied. The following example shows the
XML definition of a bar chart style:
<?xml version="1.0" ?>
<AdvancedStyle>
<BarChartStyle width="30" height="25" show_x_axis="true">
<Bar name="1990" color="#FF0000" />
<Bar name="1995" color="#FFC800" />
<Bar name="1998" color="#0000FF" />
<Bar name="2000" color="#00FF00" />
<Bar name="2002" color="#00FFFF" />
</BarChartStyle>
</AdvancedStyle>
In the preceding example, width and height specify the overall size of the bar chart,
including all individuals bars within it.
When a bar chart is drawn on a feature based on a set of values associated with that
feature, the height of each bar can be determined by either of two approaches: locally
scaled or globally scaled. A locally scaled bar chart determines the height of each bar
only from the associated values for that feature; and thus, for example, you cannot
compare the second bar of one chart to the second bar on another chart on the same
theme. A globally scaled bar chart uses the same bar scale for all charts on the map;
A-14
Appendix A
Advanced Styles
and thus, for example, you can compare the second bar of one chart to the second bar
on another chart on the same theme.
So, if you want to compare bars not only within the same chart, but also among all the
charts showing on the map, you must use globally scaled bar chart style by specifying
share_scale="true" in the definition of the bar chart style, as shown in the following
example:
<?xml version="1.0" ?>
<AdvancedStyle>
<BarChartStyle width="40" height="30" share_scale="true"
min_value="0.0" max_value="100">
<Bar name="1990" color="#FF0000" />
<Bar name="1995" color="#FFC800" />
<Bar name="1998" color="#0000FF" />
<Bar name="2000" color="#00FF00" />
<Bar name="2002" color="#00FFFF" />
</BarChartStyle>
</AdvancedStyle>
When the bar chart style in the preceding example is applied to a theme, the map
visualization component considers the global range of values of all features in that
theme, and then determines the height of each bar based on where a specific value
falls in the global range from the minimum value to the maximum value.
A.6.6 Collection Styles
A collection advanced style is simply a collection of other types of styles that are
applied together to a feature. This can result in faster rendering of a collection theme
compared to using multiple themes based on different styles.
For example, a bar chart style, when applied to a county, draws only the bar chart
somewhere inside the county, but the county itself (its boundary and interior area) is
not drawn. However, you probably want to see the underlying boundaries of the
counties, to see which bar chart belongs to which county. To do this without a
collection style, you would have to define a second theme in which each county is
being associated with a color or area style. This approach would result in two
rendering passes (because two themes are involved) for essentially the same group of
features.
However, by using a collection style in this example, you can define a single style that
refers to both the bar chart and the color or area style, and then apply the collection
style to the theme for the counties. This theme, when rendered by the map
visualization component, will show both the bar charts and the boundaries on the map.
Another typical use of a collection style is for rendering collection type topology
features, each of which can contain multiple types of geometries, such as polygons
(areas), points, and lines. In such cases, a collection style can include styles that are
most appropriate for each type of geometry in a collection topology feature.
The following example shows the XML definition of a collection style:
<?xml version="1.0" standalone="yes"?>
<AdvancedStyle>
<CollectionStyle>
<style name="C.COUNTIES" shape="polygon" />
<style name="L.PH" shape="line" />
<style name="M.CIRCLE" shape="point" />
A-15
Appendix A
Advanced Styles
</CollectionStyle>
</AdvancedStyle>
A.6.7 Variable Pie Chart Styles
A variable pie chart generates a series of pie circles of varying sizes for each bucket.
You specify the pie slice information, the start (smallest) radius size for a pie circle,
and the radius size increment between two consecutive circles.
Variable pie chart styles are conceptually similar to variable marker styles. With a
variable marker style the base marker size varies, whereas with the variable pie chart
style the circle radius varies.
The following example creates a definition for a variable pie chart style with four
buckets, each associated with different sizes (in increments of 4) of a circle with start
radius of 5. The circle radius for the first bucket has a radius of 5 display units, the
circle for the second bucket has a radius of 9 display units, and so on.
<?xml version="1.0" ?>
<AdvancedStyle>
<VariablePieChartStyle startradius="5" increment="4">
<PieSlice name="WHITE" color="#FFFFFF"/>
<PieSlice name="BLACK" color="#000000"/>
<PieSlice name="HISPANIC" color="#FF0000"/>
<Buckets>
<RangedBucket seq="0" label="0 - 6194757.2" low="0" high="6194757.2" />
<RangedBucket seq="1" label="6194757.2 - 1.23895144E7" low="6194757.2"
high="1.23895144E7"/>
<RangedBucket seq="2" label="1.23895144E7 - 1.85842716E7" low="1.23895144E7"
high="1.85842716E7"/>
<RangedBucket seq="3" label="1.85842716E7 - 2.47790288E7" low="1.85842716E7"
high="2.47790288E7"/>
<RangedBucket seq="4" label="2.47790288E7 - 3.0973786E7" low="2.47790288E7"
high="3.0973786E7"/>
</Buckets>
</VariablePieChartStyle>
</AdvancedStyle>
A.6.8 Heat Map Styles
A heat map style can be used to generate a two-dimensional (2D) color map of any
point-type data set. The colors represent the distribution density or pattern of the
points or events across the region. Internally, the map visualization component creates
a 2D matrix and assigns a value to each grid cell based on the result of a distanceweighted algorithm run against the point data set.
You can create a heat map style using the Map Builder tool, and assign it as the
rendering style for a point-type geometry theme. You can then add this theme to a
base map, or add it as a theme-based FOI layer to an interactive Oracle Maps
application. Figure A-3 shows a map displayed using a theme based on a heat map
style. This map shows the concentration of pizza restaurants: red areas have the
highest concentration of pizza restaurants, with concentrations progressively lower for
orange, yellow, dark green, lighter green, pale green, and white areas.
A-16
Appendix A
Advanced Styles
Figure A-3
Heat Map Showing Pizza Restaurant Concentration
The following example creates a definition for a heat map style.
<?xml version="1.0" ?>
<AdvancedStyle>
<HeatMapStyle>
<color_stops num_steps="200" alpha="128">
FFFFFF,00FF00, FFC800,FF0000
</color_stops>
<spot_light_radius>75.0mile</spot_light_radius>
<grid_sample_factor>2.5</grid_sample_factor>
<container_theme>THEME_DEMO_STATES</container_theme>
</HeatMapStyle>
</AdvancedStyle>
The preceding example defines these essential aspects of the heat map:
•
Color stops. Color stops are used to generate a color gradient. In this example,
the color gradient will go from white (maps to grid cells with a zero value) to green,
to orange, and finally to full red (maps to grid cells with highest values). The
gradient will have 200 colors that span these 4 color stops. All the colors will have
an alpha value of 128 (half transparent, where 0 would be fully transparent and
255 would be opaque).
•
Spot light radius. The spot light radius defines the radius around each grid cell
where events or points within this radius will be contributing to the final aggregated
value of that cell. The contribution of each point decreases as its distance from the
cell center increases, and becomes zero beyond this radius.
A-17
Appendix A
Themes: Styling Rules
You can specify the radius in pixels or in a real ground unit such as mile. When
you specify the radius in pixels (the default if you do not specify a unit), the
mapping from the color gradient to the grid cells will vary as the user zooms in and
out on the map. This occurs because the number of points fall within the radius is
constantly changing as the user zooms in and out. To achieve a fixed heat map
regardless of map scale, you must specify the spotlight radius in a ground unit
such as meter, km, or mile. The preceding example uses mile.
•
Grid sample factor. The grid sample factor is used to sample the current map
window size when creating the internal matrix or grid for heat map calculation. For
example, a sample factor of 4 means that the internal heat map grid will be onefourth (0.25) the actual map window size. So, if the map is 1000x1000 pixels, the
internal heat map grid is 250x250. Thus, the lower the grid sample factor value,
the larger the internal heat map grid will be; and the higher the value, the smaller
the internal heat map grid will be.
The grid sample factor value probably has more effect on heat map rendering
performance than any other attribute, because a large internal heat map grid
(resulting from a low grid sample factor value) will significantly increase the overall
computation time. A good general guideline is to specify a grid sample factor value
high enough so that the internal heat map grid will be 512x512 pixels or smaller.
•
Container theme name. The container theme name specifies the name of a
theme (predefined geometry theme in the same database schema) that defines
the boundary of the map for the heat map theme. For example, if you are
generating a heat map for a point data set that scatters all over the entire United
States of America, choose a theme that represents the US national boundary or all
the states as its container theme.
The specified container theme does not affect how the heat map itself is calculated
(which is solely based on the point distribution and the spotlight radius). Instead,
the container theme it masks out all colored cells that are outside the boundary of
the study region. This helps to ensure a "clean" look for the heat map.
After you create a heat map style, you can create a theme for point data and assign
the new heat map style as the rendering style for the theme.
Unlike other types of advanced styles, heat map styles do not require any attribute or
value columns.
Labels are not supported for themes rendered using heat map styles.
A.7 Themes: Styling Rules
A theme definition contains one <styling_rules> element, which may have several
other elements depending on the theme type.
This <styling_rules> element is specified in the STYLING_RULES column of the
USER_SDO_THEMES metadata view, using the following DTD:
<!ELEMENT styling_rules (rule+, hidden_info?, join_table?, join_columns?,
operations?, bitmap_masks?, parameters?)>
<!ATTLIST styling_rules theme_type
CDATA #IMPLIED
key_column
CDATA #IMPLIED
caching
CDATA #IMPLIED "NORMAL"
image_format
CDATA #IMPLIED
image_column
CDATA #IMPLIED
image_resolution CDATA #IMPLIED
image_unit
CDATA #IMPLIED
A-18
Appendix A
Themes: Styling Rules
raster_id
raster_table
raster_pyramid
raster_bands
polygon_mask
transparent_nodata
network_name
network_level
topology_name
service_url
srs
feature_ids
provider_id
srid
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
CDATA
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED
#IMPLIED>
<!ELEMENT rule (features, label?, rendering?)>
<!ATTLIST rule column CDATA #IMPLIED>
<!ELEMENT features (#PCDATA?, link?, node?, path?)>
<!ATTLIST features style CDATA #REQUIRED>
<!ELEMENT label (#PCDATA?, link?, node?, path?)>
<!ATTLIST label column CDATA #REQUIRED
style CDATA #REQUIRED>
<!ELEMENT link (#PCDATA)>
<!ATTLIST link style
direction_style
direction_position
direction_markersize
column
CDATA
CDATA
CDATA
CDATA
CDATA
#REQUIRED
#IMPLIED
#IMPLIED
#IMPLIED
#REQUIRED>
<!ELEMENT node (#PCDATA)>
<!ATTLIST node style
CDATA #REQUIRED
markersize CDATA #IMPLIED
column
CDATA #REQUIRED>
<!ELEMENT path (#PCDATA)>
<!ATTLIST path ids
CDATA
styles CDATA
style CDATA
column CDATA
#REQUIRED
#REQUIRED
#REQUIRED
#REQUIRED>
<!ELEMENT hidden_info (field+)>
<!ELEMENT field (#PCDATA)>
<!ATTLIST field column CDATA #REQUIRED
name CDATA #IMPLIED>
<!ELEMENT join_table EMPTY>
<!ATTLIST join_table name
start_measure
end_measure
measure
CDATA
CDATA
CDATA
CDATA
#REQUIRED
#IMPLIED
#IMPLIED
#IMPLIED>
<!ELEMENT join_columns EMPTY>
<!ATTLIST columns lrs_table_column CDATA #REQUIRED
join_table_column CDATA #REQUIRED>
<!ELEMENT rendering (style+)>
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Appendix A
Themes: Styling Rules
<!ELEMENT style (substyle?)>
<!ATTLIST style name
CDATA #REQUIRED
value_columns CDATA #IMPLIED>
<!ELEMENT substyle (#PCDATA)>
<!ATTLIST substyle name
CDATA #REQUIRED
value_columns CDATA #REQUIRED
changes
CDATA #IMPLIED>
<!ELEMENT operations (operation?)>
<!ELEMENT operation (parameter?)>
<!ATTLIST operation name CDATA #REQUIRED>
<!ELEMENT parameters (parameter?)>
<!ELEMENT parameter (#PCDATA)>
<!ATTLIST parameter name CDATA #REQUIRED
value DATA #REQUIRED>
<!ELEMENT bitmap_masks (mask+)>
<!ELEMENT mask (#PCDATA)>
<!ATTLIST mask raster_id
raster_table
layers
zeromapping
onemapping
CDATA
CDATA
CDATA
CDATA
CDATA
#REQUIRED
#REQUIRED
#REQUIRED
#IMPLIED
#IMPLIED>
The <styling_rules> element can have a theme_type attribute, which is used mainly for
certain types of predefined themes. (The default theme_type attribute value is geometry,
which indicates that the theme is based on spatial geometries.) The theme_type
attribute values for these special types of predefined themes are as follows:
•
annotation specifies an annotation text theme. Annotation text themes are
explained in Annotation Text Themes.
•
geom_custom specifies a custom geometry theme. You must also specify the
provider_id and srid attributes. Custom geometry themes are explained in
Custom Geometry Themes.
•
georaster specifies a GeoRaster theme. To use specified GeoRaster data (but not
if you use a query condition to retrieve the GeoRaster data), you must also specify
the raster_id and raster_table attributes. You can also specify the raster_pyramid,
raster_bands, polygon_mask, and transparent_nodata attributes. GeoRaster themes
are explained in GeoRaster Themes.
•
image specifies an image theme. You must also specify the image_format and
image_column attributes, and you can specify the image_resolution and image_unit
attributes. Image themes are explained in Image Themes.
•
network specifies a network theme. You must also specify the network_name
attribute. You can specify the network_level attribute, but the default value (1) is
the only value currently supported. Network themes are explained in Network
Themes.
•
topology specifies a topology theme. You must also specify the topology_name
attribute. Topology themes are explained in Topology Themes.
•
wfs specifies a WFS theme. You must also specify the service_url and srs
attributes. WFS themes are explained in WFS Themes.
A-20
Appendix A
Themes: Styling Rules
The <styling_rules> element can have a key_column attribute. This attribute is needed
only if the theme is defined on a join view (a view created from multiple tables). In such
a case, you must specify a column in the view that will serve as the key column to
uniquely identify the geometries or images in that view. Without this key column
information, the map visualization component will not be able to cache geometries or
images in a join view.
The <styling_rules> element can have a caching attribute, which specifies the caching
scheme for each predefined theme. The caching attribute can have one of the following
values: NORMAL (the default), NONE, or ALL.
•
NORMAL causes the map visualization component to try to cache the geometry data
that was just viewed, to avoid repeating the costly unpickling process when it
needs to reuse the geometries. Geometries are always fetched from the database,
but they are not used if unpickled versions are already in the cache.
•
NONE means that no geometries from this theme will be cached. This value is useful
when you are frequently editing the data for a theme and you need to display the
data as you make edits.
•
ALL causes the map visualization component to pin all geometry data of this theme
entirely in the cache before any viewing request. In contrast to the default value of
NORMAL, a value of ALL caches all geometries from the base table the first time the
theme is viewed, and the geometries are not subsequently fetched from the
database.
For detailed information about the caching of predefined themes, see Caching of
Predefined Themes.
Each <rule> element must have a <features> element and can have a <label> element
and a <rendering> element. The <rendering> element can be used to define multiple
render styles, and in this case the render style in the <features> element may be
undefined. If the render style in the <features> element is defined and <rendering>
element is also defined, the map visualization component will first render the style in
the <features> element and then render the styles in <rendering> element. (The
<rendering> element is explained later in this section.)
The optional column attribute of a <rule> element specifies one or more attribute
columns (in a comma-delimited list) from the base table to be put in the SELECT list of
the query generated by the map visualization component. The values from such
columns are usually processed by an advanced style for this theme. The following
example shows the use of the column attribute:
<?xml version="1.0" standalone="yes"?>
<styling_rules >
<rule column="TOTPOP">
<features style="V.COUNTY_POP_DENSITY"> </features>
</rule>
</styling_rules>
In the preceding example, the theme's geometry features will be rendered using an
advanced style named V.COUNTY_POP_DENSITY. This style will determine the color for
filling a county geometry by looking up numeric values in the column named TOTPOP
in the base table for this theme.
Each <features> element for a network theme must have a <link>, <node>, or <path>
element, or some combination of them. (The <link>, <node>, and <path> elements apply
only to network themes, which are explained in Network Themes.) The following
example shows the styling rules for a network theme to render links and nodes.
A-21
Appendix A
Themes: Styling Rules
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="network"
network_name="LRS_TEST" network_level="1">
<rule>
<features>
<link style="C.RED"
direction_style="M.IMAGE105_BW"
direction_position="0.85"
direction_markersize="8"></link>
<node style="M.CIRCLE" markersize="5"></node>
</features>
</rule>
</styling_rules>
A <label> element must have a SQL expression as its element value for determining
whether or not a label will be applied to a feature. The column attribute specifies a SQL
expression for text values to label features, and the style attribute specifies a text style
for rendering labels.
The <rendering> element can be used to define multiple rendering styles. The styles
are rendered in the order that they appear. Each style in a <rendering> element is
defined by a <style> element, which must specify the name attribute and can specify the
value_columns attribute. (The value_columns attribute is used with advanced styles, and
the column names are added to the list of attributes defined in the column attribute of
<rule> element.)
In the <rendering> element, each <style> element can have a <substyle> element that
defines the attributes for filling the feature. A <substyle> element must specify the name
attribute and can specify the value_columns and changes attributes. For the changes
attribute, only the FILL_COLOR value is supported.
The following example shows the styling rules for a geometry theme using the
<rendering> element. It defines an advanced style named V.POIVMK to render the
feature shape and an advanced substyle named V.POIBKT to fill the feature shape.
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<rule>
<features> </features>
<label column="NAME" style="T.STREET2"> 1 </label>
<rendering>
<style name="V.POIVMK" value_columns="FEATURE_CODE">
<substyle name="V.POIVBKT" value_columns="POINT_ID" changes="FILL_COLOR"/>
</style>
</rendering>
</rule>
</styling_rules>
For more information about using the <rendering> element to apply multiple rendering
styles in a single styling rule, see Applying Multiple Rendering Styles in a Single
Styling Rule.
The <hidden_info> element specifies the list of attributes from the base table to be
displayed when the user moves the mouse over the theme's features. The attributes
are specified by a list of <field> elements.
Each <field> element must have a column attribute, which specifies the name of the
column from the base table, and it can have a name attribute, which specifies the
A-22
Appendix A
Base Maps
display name of the column. (The name attribute is useful if you want a text string other
than the column name to be displayed.)
The <join_table> element specifies the table name and its one or two columns for the
measurements. It may contain one measure column for features of point type or two
measure columns for features of line string type. The measure column or columns are
used for the linear referencing process when joining with a LRS table, which has an
LRS geometry column.
The <join_columns> element specifies one column of the LRS table (which has a LRS
geometry column), and one column from the join table (which has one or two measure
columns). These two columns are used to join the LRS table and the join table.
The <operations> element specifies the list of image processing operations to be
applied on a GeoRaster theme. The operations are specified by a list of <operation>
elements.
The <operation> element specifies the image processing operator and its parameters
to be applied on a GeoRaster theme. Each <operation> element may have a list of
<parameters> elements.
The <parameters> element defines a list of parameters to be used on a specific task.
The parameters are specified by a list of <parameter> elements.
The <parameter> element must have the name and value attributes defined.
The <bitmap_masks> element defines the image mask attributes to be used with a
GeoRaster theme. The bitmap masks are specified by a list of <mask> elements.
The <mask> element specifies a bitmap mask to be applied on a GeoRaster object. The
raster_id, raster_table, and layers attributes must be defined, while the zeromapping
and onemapping attributes are optional.
See Styling Rules in Predefined Spatial Geometry Themes for more information about
styling rules and for an example.
A.8 Base Maps
A base map definition consists of one or more themes.
The XML definition of a base map is specified in the DEFINITION column of the
USER_SDO_MAPS metadata view, using the following DTD:
<!ELEMENT map_definition (theme+)>
<!ELEMENT theme EMPTY>
<!ATTLIST theme name CDATA #REQUIRED
name
CDATA #REQUIRED
datasource
CDATA #IMPLIED
template_theme
CDATA #IMPLIED
max_scale
CDATA #IMPLIED
min_scale
CDATA #IMPLIED
label_always_on
(TRUE|FALSE) "FALSE"
fast_unpickle
(TRUE|FALSE) "TRUE"
mode
CDATA #IMPLIED
min_dist
CDATA #IMPLIED
fixed_svglabel
(TRUE|FALSE) "FALSE"
visible_in_svg
(TRUE|FALSE) "TRUE"
selectable_in_svg
(TRUE|FALSE) "FALSE"
A-23
Appendix A
Map Tile Layers
part_of_basemap
simplify_shapes
transparency
minimum_pixels
onclick
onmousemove
onmouseover
onmouseout
workspace_name
workspace_savepoint
workspace_date
workspace_date_format
fetch_size
timeout
(TRUE|FALSE) "FALSE"
(TRUE|FALSE) "TRUE"
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
CDATA #IMPLIED
>
The <map_definition> element contains one or more <theme> elements. Themes are
rendered on a map on top of each other, in the order in which they are specified in the
definition.
See Maps for more information about defining base maps and for an example.
A.9 Map Tile Layers
An Oracle Maps map tile layer which assembles and displays pregenerated map
image tiles from the map tile server,
Tis rpocess is described in Map Tile Layer Configuration. The XML configuration
settings of a map tile layer is defined using the following DTD:
<!ELEMENT map_tile_layer ((internal_map_source|external_map_source), tile_storage,
coordinate_system, tile_image, , tile_dpi?, tile_meters_per_unit?, zoom_levels,
auto_update?, themes?)>
<!ATTLIST map_tile_layer
name CDATA #REQUIRED
image_format CDATA #IMPLIED
http_header_expires CDATA #IMPLIED
utfgrid (TRUE|FALSE) "FALSE"
utfgrid_resolution CDATA #IMPLIED
concurrent_fetching_threads CDATA #IMPLIED
fetch_larger_tile (TRUE|FALSE) "TRUE"
persistent_tiles (TRUE|FALSE) "TRUE">
<!ELEMENT internal_map_source EMPTY>
<!ATTLIST internal_map_source
data_source CDATA #REQUIRED
base_map CDATA #REQUIRED
bgcolor CDATA #IMPLIED
out_of_bounds_color CDATA #IMPLIED
antialias (TRUE|FALSE) "TRUE">
<!ELEMENT external_map_source (properties?)>
<!ATTLIST external_map_source
url CDATA #REQUIRED
request_method CDATA #REQUIRED
timeout CDATA #IMPLIED
adapter_class CDATA #REQUIRED
proxy_host CDATA #IMPLIED
proxy_port CDATA #IMPLIED
clipping_buffer CDATA #IMPLIED>
A-24
Appendix A
Map Tile Layers
<!ELEMENT properties (property+) >
<!ELEMENT property EMPTY >
<!ATTLIST property
name CDATA #REQUIRED
value CDATA #REQUIRED>
<!ELEMENT tile_storage EMPTY >
<!ATTLIST tile_storage
root_path CDATA #REQUIRED
xyz_storage_scheme (TRUE|FALSE) "FALSE">
<!ELEMENT coordinate_system EMPTY >
<!ATTLIST coordinate_system
srid CDATA #REQUIRED
minX CDATA #REQUIRED
minY CDATA #REQUIRED
maxX CDATA #REQUIRED
maxY CDATA #REQUIRED>
<!ELEMENT tile_bound (coordinates)>
<!ELEMENT coordinates (#PCDATA)>
<!ELEMENT tile_image EMPTY >
<!ATTLIST tile_image
width CDATA #REQUIRED
height CDATA #REQUIRED>
<!ELEMENT tile_dpi EMPTY >
<!ATTLIST tile_dpi
value CDATA #REQUIRED>
<!ELEMENT tile_meters_per_unit EMPTY >
<!ATTLIST tile_meters_per_unit
value CDATA #REQUIRED>
<!ELEMENT zoom_levels (zoom_level+)>
<!ATTLIST zoom_levels
levels CDATA #REQUIRED
min_scale CDATA #IMPLIED
max_scale CDATA #IMPLIED
min_tile_width CDATA #IMPLIED
min_tile_height CDATA #IMPLIED>
<!ELEMENT zoom_level (tile_bound?)>
<!ATTLIST zoom_level
level CDATA #REQUIRED
level_name CDATA #IMPLIED
description CDATA #IMPLIED
scale CDATA #REQUIRED
tile_width CDATA #REQUIRED
tile_height CDATA #REQUIRED>
<!ELEMENT auto_update (dirty_mbr_table_name,logtable_name)>
<!ATTLIST auto_update
finest_level_to_refresh CDATA #REQUIRED
dirty_mbr_batch CDATA #REQUIRED
dirty_mbr_cap CDATA #REQUIRED>
<!ELEMENT dirty_mbr_table_name EMPTY>
A-25
Appendix A
Map Tile Layers
<!ATTLIST dirty_mbr_table_name
name CDATA #REQUIRED>
<!ELEMENT logtable_name EMPTY>
<!ATTLIST logtable_name
name CDATA #REQUIRED>
<!ELEMENT themes (theme)>
<!ATTLIST auto_update
finest_level_to_refresh CDATA #REQUIRED
dirty_mbr_batch CDATA #REQUIRED
dirty_mbr_cap CDATA #REQUIRED>
<!ELEMENT theme EMPTY>
<!ATTLIST theme
name CDATA #REQUIRED
from_level CDATA #REQUIRED
to_level CDATA #REQUIRED>
A-26
B
Creating and Registering a Custom Spatial
Data Provider
This appendix shows a sample implementation of a spatial data provider, and explains
how to register this provider to be used with the map visualization component.
The complete implementation can be found under the map visualization component
web/demo/spatialprovider directory. The implementation uses then following files:
•
us_bigcities.xml: sample XML file that the provider parses
•
customSpatialProviderSample.java: Java implementation of the spatial data
provider
•
spatialprovider.jar: jar file with the compiled version of the
customSpatialProviderSample.java source file
The us_bigcities.xml file has sections to define the data attributes, the data extents,
and the feature information, including the geometry (in GML format) and the attribute
values. This file includes the following:
<?xml version="1.0" standalone="yes"?>
<spatial_data>
<data_attributes>
<attribute name="city" type="string" />
<attribute name="state_abrv" type="string" />
<attribute name="pop90" type="double" />
</data_attributes>
<data_extents>
<xmin> -122.49586 </xmin>
<ymin> 29.45765 </ymin>
<xmax> -73.943849 </xmax>
<ymax> 42.3831 </ymax>
</data_extents>
<geoFeature>
<attributes> New York,NY,7322564 </attributes>
<geometricProperty>
<Point>
<coordinates>-73.943849, 40.6698</coordinates>
</Point>
</geometricProperty>
</geoFeature>
. . .
</spatial_data>
•
Implementing the Spatial Provider Class
The spatial provider class interface must be implemented.
B-1
Appendix B
Implementing the Spatial Provider Class
•
Registering the Spatial Provider with the Map Visualization Component
To register the spatial provider with the map visualization component, add the
following in the spatial provider section of the map visualization component
configuration file, and then restart the map visualization component.
•
Rendering the External Spatial Data
To enable you to render the sample external spatial data that comes with the map
visualization component kit, create a data source pointing to this data.
B.1 Implementing the Spatial Provider Class
The spatial provider class interface must be implemented.
The provider must implement the class interface shown in Custom Geometry Themes.
Example B-1 contains the partial code for the spatial provider in the supplied demo.
Note that this sample code is deliberately simplified; it is not optimized, and the
provider does not create any spatial indexing mechanism.
After you have implemented the provider code, compile it and generate a jar file with
this compiled class. The file spatialprovider.jar in the demo directory contains the
compiled version of this sample code, and you can use it directly. Copy this jar file to a
directory that is part of the map visualization component's CLASSPATH definition,
such as the web/WB-INF/lib directory.
Example B-1
Implementing the Spatial Provider Class
package spatialprovider.samples;
import
import
import
import
import
import
import
import
import
import
import
import
import
import
import
import
import
import
import
java.awt.geom.Point2D;
java.awt.geom.Rectangle2D;
java.io.File;
java.util.ArrayList;
java.util.Properties;
java.util.StringTokenizer;
java.util.Vector;
javax.xml.parsers.DocumentBuilder;
javax.xml.parsers.DocumentBuilderFactory;
oracle.mapviewer.share.Field;
oracle.mapviewer.share.ext.SDataProvider;
oracle.mapviewer.share.ext.SDataSet;
oracle.mapviewer.share.ext.SObject;
org.w3c.dom.Document;
org.w3c.dom.NamedNodeMap;
org.w3c.dom.Node;
org.w3c.dom.NodeList;
oracle.spatial.geometry.JGeometry;
oracle.spatial.util.GML;
public class CustomSpatialProviderSample implements SDataProvider
{
...
/**
* Constructor.
*/
public CustomSpatialProviderSample()
{
...
}
B-2
Appendix B
Implementing the Spatial Provider Class
/**
* Returns the initialization parameters for the provider.
* The "datadir" parameter should be registered in the map visualization component
* configuration file and can be used to access the data.
* @return
*/
public String[] getInitParameterNames()
{
return new String[]{ "datadir" };
}
/**
* Returns runtime parameter names. Runtime parameters are additional parameters
* that the provider may use when retrieving the data objects.
* @return
*/
public String[] getRuntimeParameterNames()
{
return new String[]{ "filename" };
}
/**
* Initializes the provider
* @param params init properties
* @return
*/
public boolean init(Properties params)
{
dataDirectory = null;
if(params == null)
return true;
dataDirectory = params.getProperty("datadir");
if(dataDirectory == null || dataDirectory.trim().length() == 0)
{
// try upper case
dataDirectory = params.getProperty("DATADIR");
if(dataDirectory == null || dataDirectory.trim().length() == 0)
System.out.println("FINE: Init properties does not define \"datadir\" parameter.");
}
return true;
}
/**
* Returns the data set (geometries plus attributes) that intersects the
* query window. In this sample the data is parsed just once and
* there is no spatial index for searching. The search is sequential.
* @param queryWin search area
* @param nonSpatialColumns attribute columns
* @param params
runtime properties
* @return
*/
public SDataSet buildDataSet(Rectangle2D queryWin,
String []nonSpatialColumns,
Properties params)
{
if(!dataParsed)
{
dataParsed = parseData(params);
if(!dataParsed)
return null;
B-3
Appendix B
Implementing the Spatial Provider Class
}
if(geometries.size() == 0)
return null;
SDataSet dataset = new SDataSet();
boolean fullExtent = isFullExtent(queryWin);
if(fullExtent)
{
for(int i=0;i<geometries.size();i++)
{
JGeometry geom = (JGeometry)geometries.get(i);
SObject obj = new SObject(geom,getGeometryAttributes(nonSpatialColumns,i));
dataset.addObject(obj);
}
}
else
{
for(int i=0;i<geometries.size();i++)
{
JGeometry geom = (JGeometry)geometries.get(i);
double []mbr = geom.getMBR();
if(mbr == null)
continue;
Rectangle2D.Double rect = new Rectangle2D.Double(mbr[0],mbr[1],
mbr[2]-mbr[0],
mbr[3]-mbr[1]);
if(rect.getWidth() == 0. && rect.getHeight() == 0.)
{
Point2D.Double pt = new Point2D.Double(mbr[0],mbr[1]);
if(queryWin.contains(pt))
{
SObject obj = new SObject(geom,getGeometryAttributes(nonSpatialColumns,i));
dataset.addObject(obj);
}
}
else if(queryWin.contains(rect) || queryWin.intersects(rect))
{
SObject obj = new SObject(geom,getGeometryAttributes(nonSpatialColumns,i));
dataset.addObject(obj);
}
}
}
if(dataset.getSize() == 0)
return null;
return dataset;
}
/**
* Returns the data provider attribute list.
* @return
*/
public Field[] getAttributeList(Properties params)
{
if(!dataParsed)
{
dataParsed = parseData(params);
if(!dataParsed)
return null;
}
if(attributes.size() == 0)
return null;
return (Field[])attributes.toArray(new Field[attributes.size()]);
}
B-4
Appendix B
Registering the Spatial Provider with the Map Visualization Component
/**
* Returns the data extents.
* @return
*/
public Rectangle2D getDataExtents(Properties params)
{
if(!dataParsed)
{
dataParsed = parseData(params);
if(!dataParsed)
return null;
}
if(extents == null || extents.length < 4)
return null;
else
return new Rectangle2D.Double(extents[0],extents[1],
extents[2]-extents[0],
extents[3]-extents[1]);
}
/**
* Builds a spatial index for the data. In this sample there is no
* spatial index. The data is loaded into memory when data is parsed.
* @return
*/
public boolean buildSpatialIndex(Properties params)
{
return true;
}
}
B.2 Registering the Spatial Provider with the Map
Visualization Component
To register the spatial provider with the map visualization component, add the
following in the spatial provider section of the map visualization component
configuration file, and then restart the map visualization component.
<s_data_provider
id="xmlProvider"
class="spatialprovider.samples.CustomSpatialProviderSample"
>
<parameters>
<parameter name="datadir" value="/temp/data" />
</parameters>
</s_data_provider>
When you restart the map visualization component, you should see a console
message that the spatial provider has been registered. For example:
2007-10-01 14:30:31.109 NOTIFICATION Spatial Provider xmlProvider has been
registered.
B-5
Appendix B
Rendering the External Spatial Data
B.3 Rendering the External Spatial Data
To enable you to render the sample external spatial data that comes with the map
visualization component kit, create a data source pointing to this data.
Example B-2 is an XML request that contains a dynamic custom geometry theme.
Example B-2
Map Request to Render External Spatial Data
<?xml version="1.0" standalone="yes"?>
<map_request
title="Custom Geometry Theme"
datasource="mvdemo"
width="500"
height="400"
bgcolor="#a6caf0"
antialiase="true"
format="PNG_STREAM"
>
<center size="40">
<geoFeature>
<geometricProperty typeName="center">
<Point>
<coordinates>-90,32</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="custom_theme" >
<custom_geom_theme
provider_id="xmlProvider"
srid="8307"
render_style="M.CIRCLE"
label_column="city"
label_style="T.CITY NAME"
datasource="mvdemo">
<parameters>
<parameter name="filename" value="/lbs/demo/spatialprovider/us_bigcities.xml"/>
</parameters>
</custom_geom_theme>
</theme>
</themes>
</map_request>
In Example B-2, the file name in the <parameter> element points to /lbs/demo/
spatialprovider/us_bigcities.xml. If the file path is not accessible to the map
visualization component, the map request may generate error messages in the log file,
such as the following:
07/09/28 10:26:47 ParseData: Can not access file: /lbs/demo/spatialprovider/
us_bigcities.xml
07/09/28 10:26:47 ParseData: File to be parsed: /temp/data\us_bigcities.xml
07/09/28 10:26:47 ParseData: File can not be accessed on provider data directory.
Copy files there.
When the map visualization component searches for the file, it first tries to access the
file using the original theme definition parameter; and if that fails, it tries the data
B-6
Appendix B
Rendering the External Spatial Data
directory defined in the map visualization component configuration file (/temp/data in
the preceding example error messages). Therefore, if the original theme definition data
path is not accessible to the map visualization component, copy the data files to the
directory defined in the configuration file before you issue the map request.
If the map visualization component can find the data file, the map request
inExample B-2 should generate an image like the one in Figure B-1.
Figure B-1
Data
Map Image Using Custom Geometry Theme and External Spatial
B-7
C
OGC WMS Support in the Map
Visualization Component
The map visualization component supports the rendering of data delivered using the
Open GIS Consortium (OGC) Web Map Service (WMS) protocol, specifically the WMS
1.1.1 and 1.3.0 implementation specifications.
The map visualization component supports the GetMap, GetFeatureInfo, and
GetCapabilities requests as defined in the OGC document 01-068r3 and 06-042.
The map visualization component does not currently support the optional Styled Layer
Descriptor capability, and map visualization component will not function as a
Cascading Map Server in this release.
•
Setting Up the WMS Interface for the Map Visualization Component
The map visualization component is preconfigured to run as a WMS service.
•
WMS Specification and Corresponding Map Visualization Component Concepts
This section describes the association between, or interpretation of, terms and
concepts used in the WMS 1.1.1 and 1.3.0 specifications and the map
visualization component.
•
Adding a WMS Map Theme
You can add a WMS map theme to the current map request. The WMS map
theme is the result of a GetMap request, and it becomes an image layer in the set
of layers (themes) rendered by the map visualization component.
C.1 Setting Up the WMS Interface for the Map Visualization
Component
The map visualization component is preconfigured to run as a WMS service.
Internally, the map visualization component translates all incoming WMS requests into
proper XML requests to the map visualization component server. For example, the
following HTTP request invokes the GetCapabilities service of a the map visualization
component server:
http://localhost:8888/mapviewer/wms?REQUEST=GetCapabilities&SERVICE=WMS&VERSION=1.1.1
or
http://localhost:8888/mapviewer/wms?REQUEST=GetCapabilities&SERVICE=WMS&VERSION=1.3.0
As shown in this example, the URL for the map visualization component WMS service
is typically http://host:port/mapviewer/wms?, where host and port refer to the host and
HTTP port of the map visualization component server. The context path /
mapviewer/wms refers to the WMS interface of map visualization component.
C-1
Appendix C
Setting Up the WMS Interface for the Map Visualization Component
Note:
All WMS requests must be on a single line, so ignore any line breaks that
might appear in WMS request examples in this chapter.
•
Required Files
•
Data Source Named wms
•
SDO to EPSG SRID Mapping File
C.1.1 Required Files
The following files are required for map visualization component WMS support:
WMSFilter.jar and classgen.jar.
•
The servlet filter and its required classes are packaged in WMSFilter.jar. This
should be located in the $MAPVIEWER_HOME/web/WEB-INF/lib directory.
•
The servlet filter also requires classgen.jar, which is part of the XML Developer's
Kit (XDK) for Java. An Oracle Database or full Oracle Fusion Middleware
installation will already have this file.
If your system does not already have the classgen.jar file, use a classgen.jar file
from the same XDK for Java version as the one that ships with your standalone
WebLogic Server version. Place this file in the $MAPVIEWER_HOME/web/WEB-INF/lib
directory or in a directory that is in the library path for WebLogic Server.
The classgen.jar and xmlparserv2.jar files must be from the same XDK release,
because the classgen.jar file depends on the xmlparserv2.jar file.
C.1.2 Data Source Named wms
You must define a map visualization component data source named wms, unless every
incoming WMS request explicitly specifies a datasource CGI parameter. All requests
that do not specify the datasource parameter are by default directed to the data source
named wms. For example, the GetCapabilities request will by default list all the
available themes that are in the wms data source. (To configure the information
returned by a GetCapabilities request, see Customizing WMS GetCapabilities
Responses.)
C.1.3 SDO to EPSG SRID Mapping File
By default, the map visualization component uses the Oracle Spatial and Graph (SDO)
native SRID (spatial reference ID) values when such information is requested in a
WMS request such as GetCapabilities. The EPSG SRID values, however, are more
widely used in WMS applications. To have the map visualization component use
EPSG SRID values when processing WMS requests and generating responses,
specify a mapping file. This mapping file is a text file that tells the map visualization
component which SDO SRID values map to which EPSG SRID values. (Each pair of
matching SRID values refers to the same spatial reference system.)
The mapping file contains lines where each line defines one pair of equivalent SRID
values in the following format:
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sdo_srid=epsg_srid
For example, the following lines define SDO SRID 8307 as equivalent to EPSG SRID
4326, and SDO SRID 81922 as equivalent to EPSG SRID 20248:
8307=4326
81922=20248
After you have created an SDO to EPSG mapping file, you can save it on the server
where the map visualization component is running, and specify its location in the map
visualization component configuration file using the <sdo_epsg_mapfile> element in the
<wms_config> element, as explained in Customizing WMS GetCapabilities Responses.
C.2 WMS Specification and Corresponding Map
Visualization Component Concepts
This section describes the association between, or interpretation of, terms and
concepts used in the WMS 1.1.1 and 1.3.0 specifications and the map visualization
component.
It also includes some parameters that are specific to the map visualization component
but that are not in the WMS 1.1.1 and 1.3.0 specifications.
•
Supported GetMap Request Parameters
•
Supported GetCapabilities Request and Response Features
•
Supported GetFeatureInfo Request and Response Features
C.2.1 Supported GetMap Request Parameters
This section describes the supported GetMap request parameters and their
interpretation by the map visualization component. (Parameters that are specific to the
map visualization component and not mentioned in the WMS 1.1.1 and 1.3.0
specifications are labeled Map Visualization Component-Only.) The supported
parameters are in alphabetical order, with each in a separate subsection. Example C-1
shows some GetMap requests. (Each URL should be entered as a single string.)
Example C-1
GetMap Requests
http://localhost:8888/mapviewer/wms?REQUEST=GetMap&VERSION=1.1.1&FORMAT=image/gif&
SERVICE=WMS&BBOX=-121,37,-119,35&SRS=EPSG:4326&LAYERS=theme_demo_states,theme_
demo_counties,theme_demo_highways,theme_demo_cities&WIDTH=580&HEIGHT=500
http://localhost:8888/mapviewer/wms?REQUEST=GetMap&VERSION=1.3.0&FORMAT=image/gif&
SERVICE=WMS&BBOX=-121,37,-119,35&CRS=EPSG:4326&LAYERS=theme_demo_states,theme_
demo_counties,theme_demo_highways,theme_demo_cities&WIDTH=580&HEIGHT=500
http://localhost:8888/mapviewer/wms?request=GetMap&version=1.3.0&crs=none
&bbox=-122,36,-121,37&width=600&height=400&format=image/png&layers=theme_us_
states&mvthemes=<themes><theme%20name="theme_us_counties"/><theme%20name="theme_
us_road1"/></themes>&legend_
request=<legend%20bgstyle="fill:%23ffffff;stroke:%23ff0000"%20profile="medium"%20p
osition="SOUTH_EAST"><column><entry%20style="v.rb1"%20tab="1"/></column></legend>&
The default data source for a GetMap request is WMS.
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The following optional GetMap parameters are not supported in the current release of
the map visualization component:
•
TIME (time dimension)
•
ELEVATION (elevation dimension)
•
SLD and WFS URLs
The Map Visualization Component-Only parameters must contain valid XML
fragments. Because these are supplied in an HTTP GET request, they must be
appropriately encoded using a URL encoding mechanism. For example, replace each
space ( ) with %20 and each pound sign (#) with %23. The following example shows the
use of such encoding:
http://localhost:8888/mapviewer/wms?request=GetMap&version=1.1.1&srs=none&bbox=-12
2,36,-121,37&width=600&height=400&format=image/png&layers=theme_us_
states&mvthemes=<themes><theme%20name="theme_us_counties"/><theme%20name="theme_
us_road1"/></themes>&legend_
request=<legend%20bgstyle="fill:%23ffffff;stroke:%23ff0000"%20profile="medium"%20p
osition="SOUTH_EAST"><column><entry%20style="v.rb1"%20tab="1"/></column></legend>&
•
BASEMAP Parameter (Map Visualization Component-Only)
•
BBOX Parameter
•
BGCOLOR Parameter
•
DATASOURCE Parameter (Map Visualization Component-Only)
•
DYNAMIC_STYLES Parameter (Map Visualization Component-Only)
•
EXCEPTIONS Parameter
•
FORMAT Parameter
•
HEIGHT Parameter
•
LAYERS Parameter
•
LEGEND_REQUEST Parameter (Map Visualization Component-Only)
•
MVTHEMES Parameter (Map Visualization Component-Only)
•
REQUEST Parameter
•
SERVICE Parameter
•
SRS (1.1.1) or CRS (1.3.0) Parameter
•
STYLES Parameter
•
TRANSPARENT Parameter
•
VERSION Parameter
•
WIDTH Parameter
C.2.1.1 BASEMAP Parameter (Map Visualization Component-Only)
The BASEMAP parameter specifies a named base map for the specified (or default) data
source. If you specify both the BASEMAP and LAYERS parameters, all themes specified in
the LAYERS parameters are added to the base map. Therefore, if you just want to get a
map using a named base map, specify the BASEMAP parameter but specify an empty
LAYERS parameter, as in the following examples:
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REQUEST=GetMap&VERSION=1.1.1&BASEMAP=demo_map&LAYERS=&WIDTH=500&HEIGHT=560&SRS=SDO:
8307&BBOX=-122,36,-120,38.5&FORMAT=image/png
REQUEST=GetMap&VERSION=1.3.0&BASEMAP=demo_map&LAYERS=&WIDTH=500&HEIGHT=560&CRS=SDO:
8307&BBOX=-122,36,-120,38.5&FORMAT=image/png
The base map name can also be part of the LAYERS parameter. In this case, the BASEMAP
parameter does not need to be defined in the URL (see LAYERS Parameter for
additional details).
C.2.1.2 BBOX Parameter
The BBOX parameter specifies the lower-left and upper-right coordinates of the
bounding box for the data from the data source to be displayed. It has the format
BBOX=minX,minY,maxX,maxY. For example: BBOX=-122,36,-120,38.5
C.2.1.3 BGCOLOR Parameter
The BGCOLOR parameter specifies background color for the map display using the RBG
color value. It has the format 0xHHHHHH (where each H is a hexadecimal value from 0 to
F). For example: BGCOLOR=0xF5F5DC (beige).
C.2.1.4 DATASOURCE Parameter (Map Visualization Component-Only)
The DATASOURCE parameter specifies the name of the data source for the GetMap or
GetFeatureInfo request. The default value is WMS. The specified data source must exist
prior to the GetMap or GetFeatureInfo request. That is, it must have been created
using the <add_data_source> MapViewer administrative request or defined in the map
visualization component configuration file (map visualization componentConfig.xml).
C.2.1.5 DYNAMIC_STYLES Parameter (Map Visualization Component-Only)
The DYNAMIC_STYLES parameter specifies a <styles> element as part of the GetMap
request..
C.2.1.6 EXCEPTIONS Parameter
For the EXCEPTIONS parameter, the only supported value is the default:
EXCEPTIONS=application/vnd.ogc.se_xml for WMS 1.1.1 and EXCEPTIONS=XML for WMS
1.3.0. The exception is reported as an XML document conforming to the Service
Exception DTD available at the following URLs:
http://schemas.opengis.net/wms/1.1.1/WMS_exception_1_1_1.dtd
http://schemas.opengis.net/wms/1.3.0/exceptions_1_3_0.xsd
The application/vnd.ogc.se_inimage (image overwritten with Exception message), and
application/vnd.ogc.se_blank (blank image because Exception occurred) options are
not supported.
C.2.1.7 FORMAT Parameter
The FORMAT parameter specifies the image format. The supported values are image/gif,
image/jpeg, image/png, image/png8, and image/svg+xml.
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The default value is image/png.
C.2.1.8 HEIGHT Parameter
The HEIGHT parameter specifies the height for the displayed map in pixels.
C.2.1.9 LAYERS Parameter
The LAYERS parameter specifies a comma-delimited list of predefined theme names to
be used for the display. The specified values are considered to a be a case-sensitive,
ordered, comma-delimited list of predefined theme names in a default data source
(named WMS) or in a named data source specified by the parameter DATASOURCE=<name>.
For example, LAYERS=THEME_DEMO_STATES,theme_demo_counties,THEME_demo_HIGHWAYS
translates to the following <themes> element in a map visualization component map
request:
<themes>
<theme name="THEME_DEMO_STATES"/>
<theme name="theme_demo_counties"/>
<theme name="THEME_demo_HIGHWAYS"/>
</themes>
The base map name can also be part of the LAYERS list. The following example
retrieves the image from a base map named DEMO_MAP:
http://localhost:7001/mapviewer/wms?VERSION=1.1.1&REQUEST=GetMap&SRS=EPSG:
4326&BBOX=-101.19489559164734,27.0,-78.80510440835268,37.0&WIDTH=965&HEIGHT=431&FORMA
T=image/
gif&BGCOLOR=0xA6CAF0&TRANSPARENT=TRUE&LAYERS=DEMO_MAP&STYLES=&EXCEPTIONS=application/
vnd.ogc.se_xml&datasource=mvdemo
See also BASEMAP Parameter (Map Visualization Component-Only).
C.2.1.10 LEGEND_REQUEST Parameter (Map Visualization Component-Only)
The LEGEND_REQUEST parameter specifies a <legend> element as part of the GetMap
request. For information about the <legend> element, see Map Legend.
C.2.1.11 MVTHEMES Parameter (Map Visualization Component-Only)
The MVTHEMES parameter specifies a <themes> element as part of the GetMap request.
The primary purpose for the MVTHEMES parameter is to support JDBC themes in a
MapViewer request. The MVTHEMES parameter is not a substitute or synonym for the
LAYERS parameter; you still must specify the LAYERS parameter.
C.2.1.12 REQUEST Parameter
The REQUEST parameter specifies the type of request. The value must be GetMap,
GetFeatureInfo, or GetCapabilities.
C.2.1.13 SERVICE Parameter
The SERVICE parameter specifies the service name. The value must be WMS.
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C.2.1.14 SRS (1.1.1) or CRS (1.3.0) Parameter
The SRS parameter (WMS 1.1.1) or the CRS parameter (WMS 1.3.0) specifies the spatial
reference system (coordinate system) for the map visualization component to use. The
value must be one of the following: SDO:srid-value (where srid-value is a numeric
Oracle Spatial and Graph SRID value), EPSG:4326 (equivalent to SDO:8307), or none
(equivalent to SDO:0).
Except for EPSG:4326 (the standard WGS 84 longitude/latitude coordinate system),
EPSG numeric identifiers are not supported. The namespace AUTO ( WMS 1.1.1) or
AUTO2 (WMS 1.3.0), for projections that have an arbitrary center of projection, is not
supported.
C.2.1.15 STYLES Parameter
The STYLES parameter is ignored. Instead, use the LAYERS parameter to specify
predefined themes for the display.
C.2.1.16 TRANSPARENT Parameter
The TRANSPARENT=TRUE parameter (for a transparent image) is supported for PNG
images, that is, with FORMAT=image/png, or FORMAT=image/png8 for indexed (8-bit) PNG
format. the map visualization component does not support transparent GIF (GIF89)
images.
C.2.1.17 VERSION Parameter
The VERSION parameter specifies the WMS version number. The value must be 1.1.1 or
1.3.0.
C.2.1.18 WIDTH Parameter
The WIDTH parameter specifies the width for the displayed map in pixels.
C.2.2 Supported GetCapabilities Request and Response Features
A WMS GetCapabilities request to the map visualization component should specify
only the following parameters:
•
REQUEST=GetCapabilities
•
VERSION=1.1.1 or VERSION=1.3.0
•
SERVICE=WMS
For example:
http://localhost:8888/mapviewer/wms?REQUEST=GetCapabilities&VERSION=1.1.1&SERVICE=WMS
or
http://localhost:8888/mapviewer/wms?REQUEST=GetCapabilities&VERSION=1.3.0&SERVICE=WMS
The response is an XML document conforming to the WMS Capabilities DTD available
at the following, depending on the value of the VERSION parameter (1.1.1 or 1.3.0):
http://schemas.opengis.net/wms/1.1.1/WMS_MS_Capabilities.dtd
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http://schemas.opengis.net/wms/1.3.0/capabilities_1_3_0.xsd
However, the current release of the map visualization component returns an XML
document containing the <Service> and <Capability> elements with the following
information:
•
The <Service> element is mostly empty, with just the required value of OGC:WMS for
the <Service.Name> element. Support for more informative service metadata is
planned for a future release of the map visualization component.
•
The <Capability> element has <Request>, <Exception>, and <Layer> elements.
•
The <Request> element contains the GetCapabilities and GetMap elements that
describe the supported formats and URL for an HTTP GET or POST operation.
•
The <Exception> element defines the exception format. The Service Exception
XML is the only supported format in this release. The <Exception> element returns
an XML document compliant with the Service Exception DTD, but it does not
report exceptions as specified in the implementation specification. The current
release simply uses the CDATA section of a <ServiceException> element to return
the OMSException returned by the map visualization component server.
•
The <Layer> element contains a nested set of <Layer> elements. The first
(outermost) layer contains a name (WMS), a title (Oracle WebMapServer Layers by
data source), and one <Layer> element for each defined data source. Each data
source layer contains a <Layer> element for each defined base map and one entry
for each valid theme (layer) not listed in any base map. Each base map layer
contains a <Layer> element for each predefined theme in the base map.
Themes that are defined in the USER_SDO_THEMES view, that have valid
entries in the USER_SDO_GEOM_METADATA view for the base table and
geometry column, and that are not used in any base map will be listed after the
base maps for a data source. These themes will have no <ScaleHint> element.
They will have their own <LatLonBoundingBox> and <BoundingBox> elements.
The Content-Type of the response is set to application/vnd.ogc.wms_xml, as required
by the WMS implementation specification.
Because the list of layers is output by base map, a given layer or theme can appear
multiple times in the GetCapabilities response. For example, the theme
THEME_DEMO_STATES, which is part of the base maps named DEMO_MAP and DENSITY_MAP,
appears twice in Example C-2, which is an excerpt (reformatted for readability) from a
GetCapabilities response.
In Example C-2, the innermost layer describes the IMAGE_LEVEL_2 theme. The
<ScaleHint> element lists the min_scale and max_scale values, if any, for that theme in
the base map definition. For example, the base map definition for IMAGE_MAP is as
follows:
SQL> select definition from user_sdo_maps where name='IMAGE_MAP';
DEFINITION
-----------------------------------------------------------------------<?xml version="1.0" standalone="yes"?>
<map_definition>
<theme name="IMAGE_LEVEL_2" min_scale="1000.0" max_scale="0.0"/>
<theme name="IMAGE_LEVEL_8" min_scale="5000.0" max_scale="1000.0"/>
<theme name="MA_ROAD3"/>
<theme name="MA_ROAD2"/>
<theme name="MA_ROAD1"/>
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<theme name="MA_ROAD0"/>
</map_definition>
In the innermost layer, the <SRS> and <BoundingBox> elements identify the SRID and the
DIMINFO information for that theme's base table, as shown in the following Spatial
and Graph metadata query:
SQL>
2
3
4
select srid, diminfo from user_sdo_geom_metadata, user_sdo_themes
where name='IMAGE_LEVEL_2' and
base_table=table_name and
geometry_column=column_name ;
SRID
---------DIMINFO(SDO_DIMNAME, SDO_LB, SDO_UB, SDO_TOLERANCE)
-------------------------------------------------------------------------------41052
SDO_DIM_ARRAY(SDO_DIM_ELEMENT('X', 200000, 500000, .5), SDO_DIM_ELEMENT('Y', 750
000, 950000, .5))
In Example C-2, the <Layer> element for a base map has an <SRS> element and a
<LatLonBoundingBox> element. The <SRS> element is empty if all layers in the base map
definition do not have the same SRID value specified in the
USER_SDO_GEOM_METADATA view. If they all have the same SRID value (for
example, 41052), the SRS element contains that value (for example, SDO:41052). The
required <LatLonBoundingBox> element currently has default values (-180,-90,180,90).
When this feature is supported by map visualization component, this element will
actually be the bounds specified in the DIMINFO column of the
USER_SDO_GEOM_METADATA view for that layer, converted to geodetic
coordinates if necessary and possible.
All layers are currently considered to be opaque and queryable. That is, all layers are
assumed to be vector layers, and not GeoRaster, logical network, or image layers.
Example C-2
GetCapabilities Response (Excerpt)
<Title>Oracle WebMapServer Layers by data source</Title>
<Layer>
<Name>mvdemo</Name>
<Title>Datasource mvdemo</Title>
<Layer>
<Name>DEMO_MAP</Name>
<Title>Basemap DEMO_MAP</Title>
<SRS>SDO:8307</SRS>
<LatLonBoundingBox>-180,-90,180,90</LatLonBoundingBox>
. . .
<Layer>
<Name>DENSITY_MAP</Name>
<Title>Basemap DENSITY_MAP</Title>
<SRS>SDO:8307</SRS>
<LatLonBoundingBox>-180,-90,180,90</LatLonBoundingBox>
<Layer>
<Name>THEME_DEMO_STATES</Name>
<Title>THEME_DEMO_STATES</Title>
<SRS>SDO:8307</SRS>
<BoundingBox SRS="SDO:8307" minx="-180" miny="-90" maxx="180"
maxy="90" resx="0.5" resy="0.5"/>
<ScaleHint min="50.0" max="4.0"/>
</Layer>
. . .
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</Layer>
<Layer>
<Name>IMAGE_MAP</Name>
<Title>Basemap IMAGE_MAP</Title>
<SRS>SDO:41052</SRS>
<LatLonBoundingBox>-180,-90,180,90</ LatLonBoundingBox>
<Layer>
<Name>IMAGE_LEVEL_2</Name>
<Title>IMAGE_LEVEL_2</Title>
<SRS>SDO:41052</SRS>
<BoundingBox SRS="SDO:41052" minx="200000" miny="500000" maxx="750000"
maxy="950000" resx="0.5" resy="0.5"/>
<ScaleHint min="1000.0" max="0.0"/>
</Layer>
. . .
</Layer>
C.2.3 Supported GetFeatureInfo Request and Response Features
This section describes the supported GetFeatureInfo request parameters and their
interpretation by the map visualization component. Example C-3 shows some
GetFeatureInfo requests.
The response is an XML document and the Content-Type of the response is text/xml.
Example C-4 is a response to a GetFeatureInfo request in Example C-3.
Most of the following sections describe parameters supported for a GetFeatureInfo
request. (Parameters that are specific to MapViewer and not mentioned in the WMS
1.1.1 specification are labeled Map Visualization Component-Only.) Specifying
Attributes to Be Queried for a GetFeatureInfo Request explains how to query attributes
in a GetFeatureInfo request.
Example C-3
GetFeatureInfo Request
http://localhost:8888/mapviewer/wms?REQUEST=GetFeatureInfo&VERSION=1.1.1&BBOX=0,-0
.0020,0.0040&SRS=EPSG:4326&LAYERS=cite:Lakes,cite:Forests&WIDTH=200&HEIGHT=100&INF
O_FORMAT=text/xml&QUERY_LAYERS=cite:Lakes,cite:Forests&X=60&Y=60
http://localhost:8888/mapviewer/wms?REQUEST=GetFeatureInfo&VERSION=1.3.0
&BBOX=0,-0.0020,0.0040&CRS=EPSG:
4326&LAYERS=cite:Lakes,cite:Forests&WIDTH=200&HEIGHT=100
&INFO_FORMAT=text/xml&QUERY_LAYERS=cite:Lakes,cite:Forests&I=60&J=60
Example C-4
GetFeatureInfo Response
<?xml version="1.0" encoding="UTF-8" ?>
<GetFeatureInfo_Result>
<ROWSET name="cite:Lakes">
<ROW num="1">
<ROWID>AAAK22AAGAAACUiAAA</ROWID>
</ROW>
</ROWSET>
<ROWSET name="cite:Forests">
<ROW num="1">
<FEATUREID>109</FEATUREID>
</ROW>
</ROWSET>
</GetFeatureInfo_Result>
•
GetMap Parameter Subset for GetFeatureInfo Requests
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•
EXCEPTIONS Parameter
•
FEATURE_COUNT Parameter
•
INFO_FORMAT Parameter
•
QUERY_LAYERS Parameter
•
QUERY_TYPE Parameter (Map Visualization Component-Only)
•
RADIUS Parameter (Map Visualization Component-Only)
•
UNIT Parameter (Map Visualization Component-Only)
•
X and Y or I and J Parameters
•
Specifying Attributes to Be Queried for a GetFeatureInfo Request
C.2.3.1 GetMap Parameter Subset for GetFeatureInfo Requests
A GetFeatureInfo request contains a subset of a GetMap request (BBOX, SRS [1.1.1] or
CRS [1.3.0], WIDTH, HEIGHT, and optionally LAYERS parameters). These parameters are
used to convert the X, Y (1.1.1) or I, J (1.3.0) point from screen coordinates to a point
in the coordinate system for the layers being queried. It is assumed all layers are in the
same coordinate system, the one specified by the SRS parameter.
C.2.3.2 EXCEPTIONS Parameter
The only supported value for the EXCEPTIONS parameter is the default: application/
vnd.ogc.se_xml for WMS 1.1.1 or xml for WMS 1.3.0. That is, only Service Exception
XML is supported. The exception is reported as an XML document conforming to the
Service Exception DTD available at the following, depending on the version (1.1.1 or
1.3.0):
http://schemas.opengis.net/wms/1.1.1/WMS_exception_1_1_1.dtd
http://schemas.opengis.net/wms/1.3.0/exceptions_1_3_0.xsd
C.2.3.3 FEATURE_COUNT Parameter
The FEATURE_COUNT parameter specifies the maximum number of features in the result
set. The default value is 1. If more features than the parameter's value interact with the
query point (X, Y), then an arbitrary subset (of the size of the parameter's value) of the
features is returned in the result set. That is, a GetFeatureInfo call translates into a
query of the following general form:
SELECT <info_columns> FROM <layer_table>
WHERE SDO_RELATE(<geom_column>,
<query_point>, 'mask=ANYINTERACT')='TRUE'
AND ROWNUM <= FEATURE_COUNT;
C.2.3.4 INFO_FORMAT Parameter
The value of the INFO_FORMAT parameter is always text/xml.
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C.2.3.5 QUERY_LAYERS Parameter
The QUERY_LAYERS parameter specifies a comma-delimited list of layers to be queried. If
the LAYERS parameter is specified, the QUERY_LAYERS specification must be a subset of
the list specified in the LAYERS parameter.
If the QUERY_LAYERS parameter is specified, any BASEMAP parameter value is ignored.
C.2.3.6 QUERY_TYPE Parameter (Map Visualization Component-Only)
The QUERY_TYPE parameter limits the result set to a subset of possibly qualifying
features by specifying one of the following values:
•
at_point: returns only the feature at the specified point.
•
nn: returns only the nearest neighbor features, with the number of results
depending on the value of the FEATURE_COUNT parameter value (see
FEATURE_COUNT Parameter). The result set is not ordered by distance.
•
within_radius (or within_distance, which is a synonym): returns only results within
the distance specified by the RADIUS parameter value (see RADIUS Parameter
(Map Visualization Component-Only)), up to the number matching the value of the
FEATURE_COUNT parameter value (see FEATURE_COUNT Parameter). The result
set is an arbitrary subset of the answer set of potential features within the specified
radius. The result set is not ordered by distance.
C.2.3.7 RADIUS Parameter (Map Visualization Component-Only)
The RADIUS parameter specifies the radius of the circular search area for a query in
which the QUERY_TYPE parameter value is within_radius (see QUERY_TYPE Parameter
(Map Visualization Component-Only)). If you specify the RADIUS parameter, you must
also specify the UNIT parameter (see UNIT Parameter (Map Visualization ComponentOnly)).
C.2.3.8 UNIT Parameter (Map Visualization Component-Only)
The UNIT parameter specifies the unit of measurement for the radius of the circular
search area for a query in which the QUERY_TYPE parameter value is within_radius (see
QUERY_TYPE Parameter (Map Visualization Component-Only)). The value must be a
valid linear measure value from the SHORT_NAME column of the
SDO_UNITS_OF_MEASURE table, for example: meter, km, or mile.
If you specify the UNIT parameter, you must also specify the RADIUS parameter (see
RADIUS Parameter (Map Visualization Component-Only)).
C.2.3.9 X and Y or I and J Parameters
The X and Y (WMS 1.1.1) or I and J (WMS 1.3.0) parameters specify the x-axis and yaxis coordinate values (in pixels), respectively, of the query point.
C.2.3.10 Specifying Attributes to Be Queried for a GetFeatureInfo Request
In a GetFeatureInfo request, the styling rule for each queryable layer (theme) must
contain a <hidden_info> element that specifies which attributes are queried and
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Adding a WMS Map Theme
returned in the XML response. The <hidden_info> element is the same as the one used
for determining the attributes returned in an SVG map request.
An example of such a styling rule as follows:
SQL> select styling_rules from user_sdo_themes where name='cite:Forests';
STYLING_RULES
-------------------------------------------------------------------------------<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="FID" name="FeatureId"/>
</hidden_info>
<rule>
<features style="C.PARK FOREST"> </features>
<label column="NAME" style="T.PARK NAME"> 1 </label>
</rule>
</styling_rules>
This styling rule specifies that if cite:Forests is one of the QUERY_LAYERS parameter
values in a GetFeatureInfo request, the column named FID is queried, and its tag in
the response document will be <FEATUREID>. The tag is always in uppercase. If no
<hidden_info> element is specified in the styling rules for the theme's query layer, then
the rowid is returned. In Example C-4, the styling rule for the cite:Lakes layer has no
<hidden_info> element; therefore, the default attribute ROWID is returned in the XML
response. The cite:Forests layer, however, does have a <hidden_info> element, which
specifies that the attribute column is FID, and that its tag name, in the response
document, should be <FEATUREID>.
C.3 Adding a WMS Map Theme
You can add a WMS map theme to the current map request. The WMS map theme is
the result of a GetMap request, and it becomes an image layer in the set of layers
(themes) rendered by the map visualization component.
To add a WMS map theme, use the WMS-specific features of the XML API (see XML
API for Adding a WMS Map Theme).
•
XML API for Adding a WMS Map Theme
•
Predefined WMS Map Theme Definition
•
Authentication with WMS Map Themes
•
Customizing GetCapabilities Responses: Additional Options
C.3.1 XML API for Adding a WMS Map Theme
To add a WMS map theme to the current map request using the map visualization
component XML API, use the <wms_getmap_request> element in a <theme> element.
For better performance, the <wms_getmap_request> element should be used only to
request a map image from a Web Map Server (WMS) implementation. That is, the
<service_url> element in a <wms_getmap_request> element should specify a WMS
implementation, not a map visualization component instance. If you want to specify a
map visualization component instance (for example, specifying <service_url> with a
value of http://mapviewer.mycorp.com:8888/mapviewer/wms), consider using a
C-13
Appendix C
Adding a WMS Map Theme
MapViewer predefined theme or a JDBC theme in the <themes> element instead of
using a <wms_getmap_request> element.
The following example shows the general format of the <wms_getmap_request> element
within a <theme> element, and it includes some sample element values and descriptive
comments:
<themes>
<theme>
<wms_getmap_request isBackgroundTheme="true">
<!-- The wms_getmap_request theme is rendered in the order it
appears in the theme list unless isBackgroundTheme is "true".
-->
<service_url> http://wms.mapsrus.com/mapserver </service_url>
<version> 1.1.1 </version>
<!-- version is optional. Default value is "1.1.1".
-->
<layers> Administrative+Boundaries,Topography,Hydrography </layers>
<!— layers is a comma-delimited list of names.
If layer names contain spaces, use '+' instead of a space -->
<!— styles is optional. It is a comma-delimited list, and it must
have the same number of names as the layer list, if specified.
If style names contain spaces, use '+' instead of a space -->
<styles/>
<srs> EPSG:4326 </srs>
<format> image/png </format>
<transparent> true </transparent>
<bgcolor> 0xffffff </bgcolor>
<exceptions> application/vnd.ogc.se_inimage </exceptions>
<vendor_specific_parameters>
<!-- one or more <vsp> elements each containing
a <name> <value> pair -->
<vsp>
<name> datasource </name>
<value> mvdemo </value>
</vsp>
<vendor_specific_parameters>
<wms_getmap_request>
</theme>
</themes>
The following attribute and elements are available with the <wms_getmap_request>
element:
•
The isBackgroundTheme attribute specifies whether or not this theme should be
rendered before the vector layers. The default value is false.
•
The <service_url> element specifies the URL (without the service parameters) for
the WMS service. Example: http://my.webmapserver.com/wms
•
The <version> element specifies the WMS version number. The value must be one
of the following: 1.0.0, 1.1.0, 1.1.1 (the default), or 1.3.0.
•
The <layers> element specifies a comma-delimited list of layer names to be
included in the map request.
•
The <styles> element specifies a comma-delimited list of style names to be
applied to the layer names in layers.
•
The <srs> element specifies the coordinate system (spatial reference system)
name. The default value is EPSG:4326.
C-14
Appendix C
Adding a WMS Map Theme
•
The <format> element specifies the format for the resulting map image. The default
value is image/png.
•
The <transparent> element specifies whether or not the layer or layers being
added should be transparent in the resulting map image. The default value is
false. To make the layer or layers transparent, specify true.
•
The <bgcolor> element specifies the RGB value for the map background color. Use
hexadecimal notation for the value, for example, 0xAE75B1. The default value is
0xFFFFFF (that is, white).
•
The <exceptions> element specifies the format for server exceptions. The default
value is application/vnd.ogc.se_inimage.
•
The <vendor_specific_parameters> element contains one or more <vsp> elements,
each of which contains a <name> element specifying the parameter name and a
<value> element specifying the parameter value.
Example C-5 shows the <wms_getmap_request> element in a map request.
Example C-5
Adding a WMS Map Theme (XML API)
<?xml version="1.0" standalone="yes"?>
<map_request
title="Raster WMS Theme and Vector Data"
datasource="mvdemo" srid="0"
width="500"
height="375"
bgcolor="#a6caf0"
antialiase="true"
mapfilename="wms_georaster" format="PNG_URL">
<center size="185340.0">
<geoFeature>
<geometricProperty typeName="center">
<Point>
<coordinates>596082.0,8881079.0</coordinates>
</Point>
</geometricProperty>
</geoFeature>
</center>
<themes>
<theme name="WMS_TOPOGRAPHY" user_clickable="false" >
<wms_getmap_request isBackgroundTheme="true">
<service_url> http://wms.mapservers.com:8888/mapserver/wms </service_url>
<layers> TOPOGRAPHY </layers>
<srs> EPSG:29190 </srs>
<format> image/png </format>
<bgcolor> 0xa6caf0 </bgcolor>
<transparent> true </transparent>
<vendor_specific_parameters>
<vsp>
<name> ServiceType </name>
<value> mapserver </value>
</vsp>
</vendor_specific_parameters>
</wms_getmap_request>
</theme>
<theme name="cl_theme" user_clickable="false">
<jdbc_query spatial_column="geom" render_style="ltblue"
jdbc_srid="82279" datasource="mvdemo"
asis="false">select geom from classes where vegetation_type = 'forests'
</jdbc_query>
C-15
Appendix C
Adding a WMS Map Theme
</theme>
</themes>
<styles>
<style name="ltblue">
<svg width="1in" height="1in">
<g class="color"
style="stroke:#000000;stroke-opacity:250;fill:#33ffff;fill-opacity:100">
<rect width="50" height="50"/>
</g>
</svg>
</style>
</styles>
</map_request>
C.3.2 Predefined WMS Map Theme Definition
The predefined XML definition for a WMS theme uses the same structure of the
parameters in XML API for Adding a WMS Map Theme, and adds the optional
capabilities_url attribute, which is used by Map Builder when editing a WMS theme.
If the capabilities_url attribute is defined, Map Builder will issue a GetCapabilities
request to populate some UI elements in the editor page.
Example C-6 shows how to create a predefined WMS theme in the metadata. The
base table and base column names can be any values, and in this example 'WMS' is
used for both.
Example C-6
Creating a Predefined WMS Theme
INSERT INTO user_sdo_themes VALUES (
'PRED_WMS_THEME',
'WMS data',
'WMS',
'WMS', '<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="wms">
<service_url> http://sampleserver1b.arcgisonline.com/arcgis/services/Specialty/
ESRI_StateCityHighway_USA/MapServer/WMSServer </service_url>
<layers> 0,1,2 </layers>
<version> 1.3.0 </version>
<srs> CRS:84 </srs>
<format> image/png </format>
<bgcolor> 0xA6CAF0 </bgcolor>
<transparent> false </transparent>
<styles> +,+,+ </styles>
<exceptions> xml </exceptions>
<capabilities_url> http://sampleserver1.arcgisonline.com/ArcGIS/services/
Specialty/ESRI_StateCityHighway_USA/MapServer/WMSServer? </capabilities_url>
</styling_rules>');
C.3.3 Authentication with WMS Map Themes
For a WMS server that requires authentication for access to the WMS data, the
following must be included in the theme definition:
•
<user> element specifying the user name
•
<password> element specifying the user password
If you use the Map Builder tool to create a WMS map theme, the password value
will be automatically encrypted. Figure C-1 shows the use of the Map Builder tool
C-16
Appendix C
Adding a WMS Map Theme
to create a WMS theme with authentication information. In this figure, the
Authentication option is checked (enabled), and User and Password are specified.
Figure C-1
Using Map Builder to Specify Authentication with a WMS Theme
Example C-7 shows how to create a WMS theme that includes authentication
information.
Example C-7
WMS Theme with Authentication Specified
<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="wms">
<service_url> http://localhost:7001/mapviewer/wms </service_url>
<user> wmsuser </user>
<password> ******* </password>
<layers> THEME_DEMO_STATES </layers>
<version> 1.1.1 </version>
<srs> EPSG:4326 </srs>
<format> image/png </format>
<bgcolor> 0xA6CAF0 </bgcolor>
<transparent> true </transparent>
<exceptions> application/vnd.ogc.se_xml </exceptions>
<vendor_specific_parameters>
<vsp>
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Appendix C
Adding a WMS Map Theme
<name> datasource </name>
<value> mvdemo </value>
</vsp>
</vendor_specific_parameters>
<capabilities_url> http://localhost:7001/mapviewer/wms? </capabilities_url>
</styling_rules>
C.3.4 Customizing GetCapabilities Responses: Additional Options
The main map visualization component configuration file has a section to customize
some information for GetCapabilities responses (see Customizing WMS
GetCapabilities Responses). However only a limited number of properties that can be
defined in that main map visualization component configuration file, and no
customization can be done for several attributes that a layer can have in
GetCapabilities response.
Effective with Release 12.1.3, a WMS configuration file (wmsConfig.xml) has been
added to the map visualization component. Any settings defined in this WMS
configuration file will override similar WMS settings defined in the main map
visualization component configuration file.
The wmsConfig.xml can include the following.
•
Custom WMS Capabilities Parameters (<custom_parameters> Element)
•
Custom WMS Capabilities Service Attributes (<service_attributes> Element)
•
Custom WMS Layer Attributes (<layer_attributes> Element)
•
Custom WMS Feature Information (<get_feature_info> Element)
C.3.4.1 Custom WMS Capabilities Parameters (<custom_parameters>
Element)
The following attributes are available with the <custom_parameters> element:
•
The host attribute specifies the host part of the service request URL that the client
should use for future WMS requests made to this map visualization component
server.
•
The port attribute specifies the port part of the service request URL that the client
should use for future WMS requests made to this map visualization component
server.
•
The protocol attribute specifies the protocol part of the service request URL that
the client should use for future WMS requests made to this map visualization
component server.
•
The default_datasource attribute specifies the base data source to be used for
retrieving the capabilities response. If this attribute is not defined, the data source
WMS is used, and that data source must exist in this map visualization component
server.
•
The public_datasources attribute specifies which data source contents are to be
listed in the getCapabilities response. If this attribute is not defined, all data source
contents that exist in server will be listed.
•
The use_text_xml attribute by default uses standard text/xml even for
getCapabilities. If this attribute is set to false, then the OGC 1.1.1 specification is
used (for example, application/vnd.ogc.wms_xml).
C-18
Appendix C
Adding a WMS Map Theme
For example:
<custom_parameters
host="www.my_corp.com" port="80" protocol="http"
default_datasource="mvdemo"
public_datasources="mvdemo, wms">
</custom_parameters>
C.3.4.2 Custom WMS Capabilities Service Attributes (<service_attributes>
Element)
The <service attributes> element overrides any of these values defined in main map
visualization component configuration file. For example:
<service_attributes>
<title>
WMS interface provided by OracleFMW MapViewer
</title>
<abstract>
This WMS service is for demonstration.
</abstract>
<keyword_list>
<keyword>Oracle</keyword>
<keyword>MapViewer</keyword>
<keyword>Spatial and Graph</keyword>
</keyword_list>
<online_resource>
http://localhost:7001/mapviewer/wms
</online_resource>
<contact_information>
<ContactPersonPrimary>
<ContactPerson>John Doe</ContactPerson>
<ContactOrganization>My Corp.</ContactOrganization>
</ContactPersonPrimary>
<ContactPosition>Sr. Manager</ContactPosition>
<ContactAddress>
<AddressType>US Street</AddressType>
<Address>1 MyCorp drv</Address>
<City>Nashua</City>
<StateOrProvince>NH</StateOrProvince>
<PostCode>03062</PostCode>
<Country>USA</Country>
</ContactAddress>
<ContactVoiceTelephone>18001122333</ContactVoiceTelephone>
<ContactFacsimileTelephone></ContactFacsimileTelephone>
<ContactElectronicMailAddress>jdoe@my_corp.com</ContactElectronicMailAddress>
</contact_information>
<Fees>None</Fees>
<AccessConstraints>None whatsoever</AccessConstraints>
</service_attributes>
C.3.4.3 Custom WMS Layer Attributes (<layer_attributes> Element)
The WMS OGC specification defines several attributes for Layers. The layer attribute
list includes abstract, keyword list, SRS list, style, attribution, and others.
The <layer_attributes> element lets you define custom attributes for map visualization
component metadata (base maps and themes). WMS Layers are associated with map
C-19
Appendix C
Adding a WMS Map Theme
visualization component themes and base maps. All Layer attributes are optional, and
if defined they will complement the GetCapabilities response.
Example C-8 shows a <layer_attributes> element with custom parameters for a base
map and for a theme. In this example, for the base map DEMO_MAP the custom
element <abstract> is defined, while for the theme THEME_DEMO_STATES the
custom elements <abstract>, <keywordlist>, <srs>, and <style> are defined. In the
<metadata> element, use the value theme for map visualization component themes and
the value basemap for map visualization component base maps in the type attribute. If
the type attribute is not defined or value is not equal to theme or basemap, then theme is
used by default.
Example C-9 shows part of a GetCapabilities response that includes these custom
attributes.
Example C-8
Custom WMS Layer Attributes
<layer_attributes>
<datasource name="mvdemo">
<metadata name="DEMO_MAP" type="basemap">
<abstract>Collection of US States</abstract>
</metadata>
<metadata name="THEME_DEMO_STATES" type="theme"
queryable="1" cascaded="0" opaque="1" noSubsets="0"
fixedWidth="500" fixedHeight="400">
<abstract>US States</abstract>
<keywordlist>keyword1,keyword2,keyword3</keywordlist>
<srs>EPSG:4203,EPSG:20248</srs>
<style>
<title>Style title</title>
<name>Style name</name>
<abstract>Style abstract</abstract>
<stylesheeturl>
<format>Stylesheet format</format>
<onlineresource>
<href>http://www.yoururl.com/styledata.html</href>
<type>simple</type>
</onlineresource>
</stylesheeturl>
<styleurl>
<format>Styles format</format>
<onlineresource>
<href>http://www.yoururl.com/style.html</href>
<type>simple</type>
</onlineresource>
</styleurl>
<legendurl>
<format>Legend format</format>
<width>500</width>
<height>500</height>
<onlineresource>
<href>http://www.yoururl.com/legendurl.html</href>
<type>simple</type>
</onlineresource>
</legendurl>
</style>
...
C-20
Appendix C
Adding a WMS Map Theme
</metadata>
</datasource>
</layer_attributes>
Example C-9
GetCapabilities Response with Custom Attributes
<Layer>
<Name>DEMO_MAP</Name>
<Title>Basemap DEMO_MAP</Title>
<Abstract>Collection of US States</Abstract>
<SRS>EPSG:4326</SRS>
<LatLonBoundingBox maxy="90.0" maxx="180.0" miny="-90.0" minx="-180.0"/>
<Layer fixedHeight="400" fixedWidth="500" noSubsets="0" opaque="1" cascaded="0"
queryable="1">
<Name>THEME_DEMO_STATES</Name>
<Title>THEME_DEMO_STATES</Title>
<Abstract>US States</Abstract>
<KeywordList>
<Keyword>keyword1</Keyword>
<Keyword>keyword2</Keyword>
<Keyword>keyword3</Keyword>
</KeywordList>
<SRS>EPSG:4326</SRS>
<SRS>EPSG:4203</SRS>
<SRS>EPSG:20248</SRS>
<BoundingBox resy="5.0E-8" resx="5.0E-8" maxy="71.33268128071118" maxx="180.0"
miny="-14.605189123107024" minx="-180.0" SRS="EPSG:4326"/>
<BoundingBox resy="5.0E-8" resx="5.0E-8" maxy="2.06926736125942E7"
maxx="5.5812377162013E7" miny="-1.54158038049741E9" minx="-5.74425799715062E8"
SRS="EPSG:4203"/>
<BoundingBox resy="5.0E-8" resx="5.0E-8" maxy="2.06929693795843E7"
maxx="6.15958436393193E7" miny="-1.74609707025816E9" minx="-6.32398501646291E8"
SRS="EPSG:20248"/>
<Style>
<Name>Style name</Name>
<Title>Style title</Title>
<Abstract>Style abstract</Abstract>
<LegendURL height="500" width="500">
<Format>Legend format</Format>
<OnlineResource xlink:href="http://www.yoururl.com/legendurl.html"
xlink:type="simple"/>
</LegendURL>
<StyleSheetURL>
<Format>Stylesheet format</Format>
<OnlineResource xlink:href="http://www.yoururl.com/styledata.html"
xlink:type="simple"/>
</StyleSheetURL>
<StyleURL>
<Format>Stylesheet format</Format>
<OnlineResource xlink:href="http://www.yoururl.com/style.html"
xlink:type="simple"/>
</StyleURL>
</Style>
<ScaleHint max="1.5E8" min="0.0"/>
</Layer>
...
</Layer>
C-21
Appendix C
Adding a WMS Map Theme
C.3.4.4 Custom WMS Feature Information (<get_feature_info> Element)
The following attributes, available with the <get_feature_info> element, can be used
define the default radius (value and unit) for predefined map visualization component
themes:
•
The name attribute specifies the name of the predefined theme.
•
The datasource attribute specifies map visualization component data source.
•
The radius attribute specifies the default radius value for theme to be used in
within_radius GetFeatureInfo requests when the radius parameter is not defined.
•
The unit attribute specifies default radius unit (default is m for meters).
For example:
<get_feature_info>
<theme name="theme_demo_states" datasource="mvdemo" radius="500" unit="km" />
</get_feature_info>
C-22
D
OGC WMTS Support in the Map
Visualization Component
The map visualization component supports the rendering of data delivered using the
Open GIS Consortium (OGC) Web Map Tile Service (WMTS) protocol, specifically the
WMS 1.0.0 implementation specifications
The map visualization component supports the GetCapabilities, GetTile, and
GetFeatureInfo requests as defined in the OGC document 07-057r7.
•
WMTS Service for MapViewer
A Web Map Tile Service (WMTS) service in MapViewer is provided through its
WMTS server, which is built on MapViewer's map cache server.
•
WMTS Operations
MapViewer supports the GetCapabilities, GetTile, and GetFeatureInfo operations
specified in the OGC WMTS 1.0.0 standard.
•
Preparing the WMTS Service for MapViewer
To prepare for using the WMTS Service for MapViewer, follow these major steps:
D.1 WMTS Service for MapViewer
A Web Map Tile Service (WMTS) service in MapViewer is provided through its WMTS
server, which is built on MapViewer's map cache server.
That is, this WMTS server delegates a client's WMTS request to MapViewer's map
cache server. The OGC operations GetCapabilities, GetTile, and GetFeatureInfo are
supported. Two kinds of encoding, KVP and REST, are supported for GetCapabilities
and GetTile operations, but for GetFeatureInfo operations only KVP encoding is
supported. For a GetFeatureInfo request, the response is encoded in one of the three
formats (specified with the infoformat attribute): text/xml, text/html, and application/
json.
In general, all map cache tile layers in MapViewer can be accessed through its WMTS
service. You can customize each map cache tile layer's accessibility by editing a
WMTS service policy file, wmtsConfig.xml, stored in the same folder as the
mapViewerConfig.xml file. In WMTS service policy file, you can limit MapViewer's WMTS
service by only publishing a subset of all map cache tile layers in MapViewer server
(see Customizing WMTS GetCapabilities Responses for details).
Example D-1 and Example D-2 show how to publish a tile layer to MapViewer's WMTS
server using a policy file. The first example shows the policy file that specifies a tile
layer, and the second shows the tile layer definition.
•
Example D-1 is a WMTS policy file. In this file, only one map cache tile layer
named TEST_TL in data source MVDEMO is published to MapViewer's WMTS
service. This policy file may also contain service provider related information.
•
Example D-2 is the map tile layer definition for the TEST_TL tile layer in the
schema for data source MVDEMO.
D-1
Appendix D
WMTS Service for MapViewer
Regardless of whether there are additional data sources in the MapViewer server, or
additional map cache tile layers in the specified data source, if the policy file is
specified as in Example D-1, the only published WMTS layer is map cache tile layer
TEST_TL in data source MVDEMO (shown in Example D-2).
Example D-1
WMTS Policy File (wmtConfig.xml)
<wmts_config>
<public_datasources>
<public_datasource name="MVDEMO">
<tile_layers>
<tile_layer name="TEST_TL"/>
</tile_layers>
</public_datasource>
</public_datasources>
<ServiceAttributes>
<ServiceIdentification>
<Title>Web Map Tile Service by myCorp</Title>
<Abstract> U.S. maps for state and county boundaries, highway networks,
and big cities.</Abstract>
<Keywords>
<Keyword>Maps</Keyword>
<Keyword>U.S. State, County Boundaries</Keyword>
<Keyword>U.S. Interstate Highways</Keyword>
<Keyword>U.S. Cities</Keyword>
</Keywords>
<Fees>none</Fees>
<AccessConstraints>none</AccessConstraints>
</ServiceIdentification>
<ServiceProvider>
<ProviderName>provider's name</ProviderName>
<ProviderSite url="http://www.myCorp.com/mySite"/>
<ServiceContact>
<IndividualName>my name</IndividualName>
<PositionName>technical support specialist</PositionName>
<ContactInfo>
<Phone>
<Voice>+1 800 321 1234</Voice>
<Facsimile>+1 800 321 1235</Facsimile>
</Phone>
<Address>
<DeliveryPoint>123 My Street</DeliveryPoint>
<City>Nashua</City>
<AdministrativeArea>New Hampshire</AdministrativeArea>
<PostalCode>12345-4321</PostalCode>
<Country>U.S.</Country>
<ElectronicMailAddress>myname@mycompany.com</ElectronicMailAddress>
</Address>
</ContactInfo>
</ServiceContact>
</ServiceProvider>
</ServiceAttributes>
</wmts_config>
Example D-2
Tile Layer Definition in the Data Source
SQL> select definition from user_sdo_cached_maps where name='TEST_TL';
DEFINITION
-------------------------------------------------------------------------------<map_tile_layer name="TEST_TL" image_format="PNG" http_header_expires="168.0"
D-2
Appendix D
WMTS Operations
concurrent_fetching_threads="3">
<internal_map_source base_map="DEMO_MAP" data_source="MVDEMO"/>
<coordinate_system srid="8307" minX="-180" maxX="180" minY="-90" maxY="90"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="2132.729583849784" max_scale="559082264.0287178">
<zoom_level tile_width="360.0000" tile_height="360.0000" scale="5.590822640287178E8"/>
<zoom_level tile_width="180.0000" tile_height="180.0000" scale="2.795411320143589E8"/>
<zoom_level tile_width="90.0000" tile_height="90.00000" scale="1.3977056600717944E8"/>
<zoom_level tile_width="45.0000" tile_height="45.00000" scale="6.988528300358972E7"/>
<zoom_level tile_width="22.5000" tile_height="22.50000" scale="3.494264150179486E7"/>
<zoom_level tile_width="11.2500" tile_height="11.25000" scale="1.747132075089743E7"/>
<zoom_level tile_width="5.6250" tile_height="5.62500" scale="8735660.375448715"/>
<zoom_level tile_width="2.8125" tile_height="2.81250" scale="4367830.1877243575"/>
<zoom_level tile_width="1.40625" tile_height="1.40625" scale="2183915.0938621787"/>
<zoom_level tile_width="0.703125" tile_height="0.703125" scale="1091957.5469310894"/>
<zoom_level tile_width="0.3515625" tile_height="0.3515625" scale="545978.7734655447"/>
<zoom_level tile_width="0.17578125" tile_height="0.17578125" scale="272989.38673277234"/>
<zoom_level tile_width="0.087890625" tile_height="0.087890625" scale="136494.693366386"/>
<zoom_level tile_width="0.0439453125" tile_height="0.0439453125" scale="68247.34668319"/>
<zoom_level tile_width="0.02197265625" tile_height="0.02197265625" scale="34123.6733415"/>
<zoom_level tile_width="0.010986328126" tile_height="0.010986328126" scale="17061.8366707"/>
<zoom_level tile_width="0.0054931640633" tile_height="0.0054931640633" scale="8530.91833539"/>
<zoom_level tile_width="0.00274658203168" tile_height="0.00274658203168" scale="4265.45916769"/>
<zoom_level tile_width="0.001373291015841" tile_height="0.001373291015841"
scale="2132.72958384"/>
</zoom_levels>
</map_tile_layer>
D.2 WMTS Operations
MapViewer supports the GetCapabilities, GetTile, and GetFeatureInfo operations
specified in the OGC WMTS 1.0.0 standard.
It also supports some MapViewer-specific parameters that are not defined in that
standard, but which make WMTS operations in MapViewer more flexible.
•
GetCapabilities Operation Support
•
GetTile Operation Support
•
GetFeatureInfo Operation Support
D.2.1 GetCapabilities Operation Support
When the MapViewer server receives a WMTS GetCapabilities request, its WMTS
server translates the definition of available map cache tile layers into an XML
document according to the OGC WMTS specification. (The accessible cache tile
layers are defined by the wmtsConfig.xml policy file if it exists; otherwise, all map cache
tile layers from all data sources are available to WMTS server are used.) Then the
XML document is returned to the client. Within this returned XML document, the
information about the service provider, if specified in the wmtsConfig.xml policy file, is
provided.
This topic includes a GetCapabilities request in KVP encoding and its response, and a
GetCapabilities request in REST encoding and its response. Regardless of whether
the request is in KVP or REST encoding, the base URL must be in the following
format:
D-3
Appendix D
WMTS Operations
http://<host>:<port>/mapviewer/wmts
where <host> and <port> refer to the host and HTTP port of the MapViewer server.
The context path /mapviewer/wmts refers to the WMTS interface of MapViewer.
Example D-3 is the response from the following example GetCapabilities request in
KVP coding:
http://localhost:8088/mapviewer/wmts?REQUEST=GetCapabilities&SERVICE=WMTS&VERSION=1.0.0
Example D-4 is the response from the following example GetCapabilities request in
REST coding:
http://localhost:8088/mapviewer/wmts/1.0.0/WMTSCapabilities.xml
In Example D-3 and Example D-4, bold text for <ows:Value> elements shows
differences in their responses when requests are in different encodings. (The encoding
to use is an application-specific preference.) In these example responses, the GetTile
operations are given in the same encoding as that of the GetCapabilities request's
encoding;, but the GetFeatureInfo operations are always in KVP encoding.
With the MapViewer WMTS server, there is no significant performance difference
between use of the two encodings.
Example D-3
Response from GetCapabilities Request in KVP Encoding
<?xml version="1.0" encoding="UTF-8"?>
<Capabilities xmlns="http://www.opengis.net/wmts/1.0"
xmlns:ows="http://www.opengis.net/ows/1.1"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:gml="http://www.opengis.net/gml"
xsi:schemaLocation="http://www.opengis.net/wmts/1.0 http://schemas.opengis.net/
wmts/1.0/wmtsGetCapabilities_response.xsd"
version="1.0.0">
<ows:ServiceIdentification>
<ows:Title>Web Map Tile Service by myCorp</ows:Title>
<ows:Abstract>U.S. maps for state and county boundaries, highway networks, and big
cities.</ows:Abstract>
<ows:Keywords>
<ows:Keyword>Maps</ows:Keyword>
<ows:Keyword>U.S. State and County Boundaries</ows:Keyword>
<ows:Keyword>U.S. Interstate Highways</ows:Keyword>
<ows:Keyword>U.S. Cities</ows:Keyword>
</ows:Keywords>
<ows:ServiceType>OGC WMTS</ows:ServiceType>
<ows:ServiceTypeVersion>1.0.0</ows:ServiceTypeVersion>
<ows:Fees>none</ows:Fees>
<ows:AccessConstraints>none</ows:AccessConstraints>
</ows:ServiceIdentification>
<ows:ServiceProvider>
<ows:ProviderName>provider's name</ows:ProviderName>
<ows:ProviderSite xlink:href="http://www.myCorp.com/mySite" />
<ows:ServiceContact>
<ows:PositionName>technical support specialist</ows:PositionName>
<ows:ContactInfo>
<ows:Phone>
<ows:Voice>+1 800 321 1234</ows:Voice>
<ows:Facsimile>+1 800 321 1235</ows:Facsimile>
</ows:Phone>
<ows:Address>
D-4
Appendix D
WMTS Operations
<ows:DeliveryPoint>123 My Street</ows:DeliveryPoint>
<ows:City>Nashua</ows:City>
<ows:AdministrativeArea>New Hampshire</ows:AdministrativeArea>
<ows:PostalCode>12345-4321</ows:PostalCode>
<ows:Country>U.S.</ows:Country>
<ows:ElectronicMailAddress>myname@mycompany.com</ows:ElectronicMailAddress>
</ows:Address>
</ows:ContactInfo>
</ows:ServiceContact>
</ows:ServiceProvider>
<ows:OperationsMetadata>
<ows:Operation name="GetCapabilities">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://localhost:8088/mapviewer/wmts?">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
<ows:Operation name="GetTile">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://localhost:8088/mapviewer/wmts?">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
<ows:Operation name="GetFeatureInfo">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://localhost:8088/mapviewer/wmts?">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
</ows:OperationsMetadata>
<Contents>
<Layer>
<ows:Title>TEST_TL</ows:Title>
<ows:Abstract>datasource:MVDEMO,layer:TEST_TL</ows:Abstract>
<ows:WGS84BoundingBox>
<ows:LowerCorner>-180.0 -90.0</ows:LowerCorner>
<ows:UpperCorner>180.0 90.0</ows:UpperCorner>
</ows:WGS84BoundingBox>
<ows:Identifier>MVDEMO:TEST_TL</ows:Identifier>
<Style isDefault="true">
D-5
Appendix D
WMTS Operations
<ows:Identifier>_null</ows:Identifier>
</Style>
<Format>image/png</Format>
<TileMatrixSetLink>
<TileMatrixSet>MVDEMO:TEST_TL:EPSG:4326</TileMatrixSet>
<TileMatrixSetLimits>
<TileMatrixLimits>
. . . . . . <!-- omitted to save space -->
<TileMatrixLimits>
<TileMatrix>MVDEMO:TEST_TL:EPSG:4326:8</TileMatrix>
<MinTileRow>0</MinTileRow>
<MaxTileRow>128</MaxTileRow>
<MinTileCol>0</MinTileCol>
<MaxTileCol>256</MaxTileCol>
</TileMatrixLimits>
. . . . . . <!-- omitted to save space -->
</TileMatrixSetLimits>
</TileMatrixSetLink>
</Layer>
<TileMatrixSet>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326</ows:Identifier>
<ows:SupportedCRS>urn:ogc:def:crs:EPSG:4326</ows:SupportedCRS>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:0</ows:Identifier>
<ScaleDenominator>5.590822641167623E8</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>2</MatrixWidth>
<MatrixHeight>2</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:1</ows:Identifier>
<ScaleDenominator>2.7954113205838114E8</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>3</MatrixWidth>
<MatrixHeight>2</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:2</ows:Identifier>
<ScaleDenominator>1.3977056602919057E8</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>5</MatrixWidth>
<MatrixHeight>3</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:3</ows:Identifier>
<ScaleDenominator>6.988528301459529E7</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>9</MatrixWidth>
<MatrixHeight>5</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:4</ows:Identifier>
<ScaleDenominator>3.494264150729764E7</ScaleDenominator>
D-6
Appendix D
WMTS Operations
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>17</MatrixWidth>
<MatrixHeight>9</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:5</ows:Identifier>
<ScaleDenominator>1.747132075364882E7</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>33</MatrixWidth>
<MatrixHeight>17</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:6</ows:Identifier>
<ScaleDenominator>8735660.37682441</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>65</MatrixWidth>
<MatrixHeight>33</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:7</ows:Identifier>
<ScaleDenominator>4367830.188412205</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>129</MatrixWidth>
<MatrixHeight>65</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:8</ows:Identifier>
<ScaleDenominator>2183915.0942061027</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>257</MatrixWidth>
<MatrixHeight>129</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:9</ows:Identifier>
<ScaleDenominator>1091957.5471030513</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>513</MatrixWidth>
<MatrixHeight>257</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:10</ows:Identifier>
<ScaleDenominator>545978.7735515257</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>1025</MatrixWidth>
<MatrixHeight>513</MatrixHeight>
</TileMatrix>
<TileMatrix>
D-7
Appendix D
WMTS Operations
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:11</ows:Identifier>
<ScaleDenominator>272989.38677576283</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>2049</MatrixWidth>
<MatrixHeight>1025</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:12</ows:Identifier>
<ScaleDenominator>136494.69338788142</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>4097</MatrixWidth>
<MatrixHeight>2049</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:13</ows:Identifier>
<ScaleDenominator>68247.34669394071</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>8193</MatrixWidth>
<MatrixHeight>4097</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:14</ows:Identifier>
<ScaleDenominator>34123.673346970354</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>16385</MatrixWidth>
<MatrixHeight>8193</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:15</ows:Identifier>
<ScaleDenominator>17061.836673485177</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>32769</MatrixWidth>
<MatrixHeight>16385</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:16</ows:Identifier>
<ScaleDenominator>8530.918336742589</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>65537</MatrixWidth>
<MatrixHeight>32769</MatrixHeight>
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:17</ows:Identifier>
<ScaleDenominator>4265.459168371294</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>131073</MatrixWidth>
<MatrixHeight>65537</MatrixHeight>
D-8
Appendix D
WMTS Operations
</TileMatrix>
<TileMatrix>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326:18</ows:Identifier>
<ScaleDenominator>2132.729584185647</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>262145</MatrixWidth>
<MatrixHeight>131073</MatrixHeight>
</TileMatrix>
</TileMatrixSet>
</Contents>
<ServiceMetadataURL xlink:href="http://localhost:8088/mapviewer/wmts?
SERVICE=WMTS&amp;VERSION=1.0.0&amp;REQUEST=getCapabilities"/>
</Capabilities>
Example D-4
Response from GetCapabilities Request in REST Encoding
<?xml version="1.0" encoding="UTF-8"?>
<Capabilities xmlns="http://www.opengis.net/wmts/1.0"
xmlns:ows="http://www.opengis.net/ows/1.1"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:gml="http://www.opengis.net/gml"
xsi:schemaLocation="http://www.opengis.net/wmts/1.0 http://schemas.opengis.net/
wmts/1.0/wmtsGetCapabilities_response.xsd"
version="1.0.0">
<ows:ServiceIdentification>
<!-- omitted to save space, the same as in KVP encoding -->
</ows:ServiceIdentification>
<ows:ServiceProvider>
<!-- omitted to save space, the same as in KVP encoding -->
</ows:ServiceProvider>
<ows:OperationsMetadata>
<ows:Operation name="GetCapabilities">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://localhost:8088/mapviewer/wmts">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>RESTful</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
<ows:Operation name="GetTile">
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://localhost:8088/mapviewer/wmts">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>RESTful</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
<ows:Operation name="GetFeatureInfo">
D-9
Appendix D
WMTS Operations
<ows:DCP>
<ows:HTTP>
<ows:Get xlink:href="http://localhost:8088/mapviewer/wmts?">
<ows:Constraint name="GetEncoding">
<ows:AllowedValues>
<ows:Value>KVP</ows:Value>
</ows:AllowedValues>
</ows:Constraint>
</ows:Get>
</ows:HTTP>
</ows:DCP>
</ows:Operation>
</ows:OperationsMetadata>
<Contents>
<Layer>
<ows:Title>TEST_TL</ows:Title>
<ows:Abstract>datasource:MVDEMO,layer:TEST_TL</ows:Abstract>
<ows:WGS84BoundingBox>
<ows:LowerCorner>-180.0 -90.0</ows:LowerCorner>
<ows:UpperCorner>180.0 90.0</ows:UpperCorner>
</ows:WGS84BoundingBox>
<ows:Identifier>MVDEMO:TEST_TL</ows:Identifier>
<Style isDefault="true">
<ows:Identifier>_null</ows:Identifier>
</Style>
<Format>image/png</Format>
<TileMatrixSetLink>
<TileMatrixSet>MVDEMO:TEST_TL:EPSG:4326</TileMatrixSet>
<TileMatrixSetLimits>
. . . . . . <!-- omitted to save space -->
<TileMatrixLimits>
<TileMatrix>8</TileMatrix>
<MinTileRow>0</MinTileRow>
<MaxTileRow>128</MaxTileRow>
<MinTileCol>0</MinTileCol>
<MaxTileCol>256</MaxTileCol>
</TileMatrixLimits>
. . . . . . <!-- omitted to save space -->
</TileMatrixSetLimits>
</TileMatrixSetLink>
<ResourceURL format="image/png" template="http://localhost:8088/mapviewer/wmts/
MVDEMO:TEST_TL/{TileMatrixSet}/{TileMatrix}/{TileRow}/{TileCol}.png"
resourceType="tile"/>
</Layer>
<TileMatrixSet>
<ows:Identifier>MVDEMO:TEST_TL:EPSG:4326</ows:Identifier>
<ows:SupportedCRS>urn:ogc:def:crs:EPSG:4326</ows:SupportedCRS>
<TileMatrix>
<ows:Identifier>0</ows:Identifier>
<ScaleDenominator>5.590822641167623E8</ScaleDenominator>
<TopLeftCorner>-180.0 90.0</TopLeftCorner>
<TileWidth>256</TileWidth>
<TileHeight>256</TileHeight>
<MatrixWidth>2</MatrixWidth>
<MatrixHeight>2</MatrixHeight>
</TileMatrix>
. . . . . . <!-- omitted to save space -->
</TileMatrixSet>
</Contents>
<ServiceMetadataURL xlink:href="http://localhost:8088/mapviewer/wmts?
D-10
Appendix D
WMTS Operations
SERVICE=WMTS&amp;VERSION=1.0.0&amp;REQUEST=getCapabilities"/>
</Capabilities>
D.2.2 GetTile Operation Support
When the MapViewer server receives a WMTS GetTile request, its WMTS server asks
the map cache server for that requested tile. The map cache server first checks the
WMTS layer's accessibility; and if the layer is accessible, it translates the requested
WMTS tile's tile-row, tile-column, and other parameters into MapViewer map cache tile
layer's specification. The map cache server then prepares that tile and returns it to the
MapViewer's WMTS server. In other words, a MapViewer WMTS layer published in
the WMTS GetCapabilities XML document can be seen as a "virtual" layer physically
mapped to the MapViewer map cache tile layer, which is managed by the MapViewer
map cache server.
Whenever the WMTS server receives a GetTile request, it requests the MapViewer
map cache server to make that tile, and then the WMTS server returns it to the client.
When the map cache server receives such requests from the WMTS server, it always
generates an image according to the specifications, such as an image's size and
bounding box. The map cache server's image generation process can be as easy as
getting the needed tiles from cache to "assemble" the requested WMTS tile (by
mosaicking and cutting); or if tiles are not available in the cache, the map cache server
requests another sever (MapViewer's map server) to generate the tiles.
This topic includes GetTile requests in KVP and REST encodings, and the response.
The following is a GetTile request in KVP coding (note that any WMTS request must
be on a single line):
http://localhost:8088/mapviewer/wmts?
SERVICE=WMTS&REQUEST=GetTile&VERSION=1.0.0&LAYER=MVDEMO:TEST_TL&STYLE=_null&format=image/
png&TileMatrixSet=MVDEMO:TEST_TL:EPSG:4326&TileMatrix=MVDEMO:TEST_TL:EPSG:4326:8&TileRow=33&TileCol=77
Figure D-1 shows the response tile image for the preceding request.
Figure D-1
Image Tile as Response to GetTile Request
D-11
Appendix D
WMTS Operations
The following is the same basic GetTile request but in REST encoding (note that any
WMTS request must be on a single line):
http://localhost:8088/mapviewer/wmts/MVDEMO:TEST_TL/MVDEMO:TEST_TL:EPSG:4326/8/33/77.png
The response image is the same as shown in Figure D-1.
•
Map Tiles in WMTS Layer and in Map Cache Tile Layer
D.2.2.1 Map Tiles in WMTS Layer and in Map Cache Tile Layer
The MapViewer map cache server may cache its tile layer's map tiles, but its WMTS
server does not cache any WMTS layer's map tiles. In other words, the WMTS server's
map tiles do not physically exist, but rather are mapped to a MapViewer map cache
tile layer.
For example, if a map cache tile layer's cache has been emptied before you send the
WMTS GetTile request in Map Tiles in WMTS Layer and in Map Cache Tile Layer,
then the following will occur:
1.
WMTS server receives the request, then it passes it to the map cache server.
2.
The map cache server converts the request into an internal image map request to
generate the tile image (with a spatial dimension defined by the tile's bounding
box, and an image dimension defined by the image size, such as 256x256).
3.
The needed map cache tile layer's tiles are identified.
4.
For each map cache tile layer's tile, the map cache server tries to get it from its
cache. If the tile is not available from its cache (which is the case in this scenario
because you just emptied the cache), a map request is sent to another server, the
MapViewer map server, to generate that tile image.
5.
After all the necessary map cache tile layer's map tiles are fetched, the WMTS tile
image is then rendered (by mosaicking and cutting if applicable) and returned.
If the client sends a request for the same WMTS tile afterward, the preceding steps will
be repeated, and the only difference is in step 4, where the required map cache tile
layer's tiles will be available from the cache. Because the most expensive processing
in step 4 is avoided, your second request to the same tile should be much faster.
In general, there is no one-to-one match between a tile in the map cache tile layer and
a tile in a WMTS layer specified by a GetTile request. This is because a MapViewer
map cache tile layer uses a coordinate system with its origin is at the lower left corner
(tile_x, tile_y), while WMTS uses a coordinate system that uses the upper left corner
as its origin (tile_column, tile_row). For example, a MapViewer's image tile at (tile_x=0,
tile_y=0) is the tile at the lower left corner. while the WMTS tile at (tile_column=0,
tile_row=0) is located at the upper left corner.
The entire data area is partitioned into tiles starting from its corresponding origin, and
the last tile in (tile_x, tile_y) or in (tile_column, tile_row) for each zoom level might not
always align exactly with the data's upper bound (for the MapViewer tile coordinate
system) or lower bound (for the WMTS tile coordinate system). Therefore, there might
be no one-to-one match for tiles between the two systems. However, when the last tile
does align exactly with the data boundary, then a one-to-one match does exist.
Using the GetTile request in Map Tiles in WMTS Layer and in Map Cache Tile Layer
as an example, if you request a WMTS tile (tile_column=77, tile_row=33) at zoom level
8, that tiles matches exactly with a map cache tile layer's tile at: (tile_x=77, tile_y=94).
These two tiles match because:
D-12
Appendix D
WMTS Operations
•
The tile layer definition (see Example D-2) ensures that there is a one-to-one
match for the WMTS tile and the map cache tile layer's tile because the last tile in
either coordinate system aligned with the data boundary exactly.
•
WMTS's tile_row 33 complements the map cache server's tile_y 94 to make the
total tile rows to be 128 (note that one's origin is the upper-left corner and the
other is the lower-left). As shown in Example D-3, the <MaxTileRow> element value
is 128.
Note also that the tile_x and tile_column values are the same, because they start
from the western boundary and works their way to the right.
When creating a tile layer in MapViewer for the WMTS service, be sure that the
<tile_dpi> element is given a value of 0.28 mm, which is equivalent in dots per inch
(dpi) notation to <tile_dpi value="90.7142857"/>. If this element is not provided, then
MapViewer's map cache tile layer may use a different value (for example, setting dpi to
96) for the tile layer when generating tiles. This different value may slow the WMTS
service and degrade the quality of its map tiles, because WMTS uses a dpi value of
90.7142857.
When creating a tile layer using the WGS84 (longitude/latitude) geodetic reference
system in MapViewer for the WMTS service, you need to make sure that the
<tile_meters_per_unit> element is given this value corresponding to an arc length of 1
degree along the equator: <tile_meters_per_unit value="111319.49079327358"/>. If the
<tile_meters_per_unit> element is not provided, then MapViewer internally calculates
a value; however, because the 111319.49079327358 value is commonly used by
other WMTS service providers for the WGS84 geodetic reference system, specifying
<tile_meters_per_unit value="111319.49079327358"/> will ensure that MapViewer's
WMTS layer matches others service provider's tile layers.
D.2.3 GetFeatureInfo Operation Support
MapViewer supports the following GetFeatureInfo operation options:
•
The standard OGC GetFeatureInfo request
•
A MapViewer-specific GetFeatureInfo request at point (x,y)
•
A MapViewer-specific GetFeatureInfo request within a bounding box
The feature information returned by these operations is based on the MapViewer base
map and theme definitions, and on features selected according to the area of interest.
The base map may define the visible scale ranges for each theme; and each theme
defines its information columns in the <field> child element of <hidden_info>, which is
a child element in the <styling_rules> element. If no information columns are specified
in a theme's <styling_rules> element, then GetFeatureInfo response will not include
any information about the features of that theme.
The area of interest is calculated in a GetFeatureInfo process for each option as
follows:
•
For a standard OGC GetFeatureInfo request, the pixel's column and row and its
tile's location at a given zoom level can be translated into a (x,y) point in the map
cache tile layer's coordinate system at the pixel's centroid. Centered at that point,
a 5 by 5 pixel window at that zoom level defines the area of interest.
•
For a MapViewer-specific (x, y) point request, it is also uses a 5 by 5 pixel window
at that level centered at the given (x,y) value as the area of interest.
D-13
Appendix D
WMTS Operations
•
For a MapViewer-specific bounding box GetFeatureInfo request option, it uses the
specified bounding box (min_x, min_y, max_x, max_y) and their corresponding
(column, row) values in the image tile at the zoom level as the area of interest.
MapViewer lets you provide an additional MapViewer-specific parameter in a
GetFeatureInfo request: a childLayer attribute (for example, childLayer=myTheme1,
myTheme2). When this parameter is provided, MapViewer only includes the features
information in the specified themes (in this example, only myTheme1 and myTheme2).
If this parameter is not provided, then all themes in the base map definition are
considered for a GetFeatureInfo request.
This topic includes the following subtopics:
•
OGC GetFeatureInfo Request
•
MapViewer GetFeatureInfo Request at an (x,y) Point
•
MapViewer GetFeatureInfo Request within a Bounding Box
These subtopics have examples that use the base map and theme definitions in
Example D-5 and Example D-6 for a tile layer named TEST_TL.
Example D-5
Base Map Definition for Tile Layer TEST_TL
<?xml version="1.0" standalone="yes"?>
<map_definition>
<theme name="THEME_DEMO_STATES" min_scale="" max_scale="0.0" scale_mode="RATIO"/>
<theme name="THEME_DEMO_COUNTIES" min_scale="8500000.0" max_scale="0.0" scale_mode="RATIO"/>
<theme name="THEME_DEMO_HIGHWAYS_LINE" min_scale="1.0E8" max_scale="4.5E7" scale_mode="RATIO"/>
<theme name="THEME_DEMO_HIGHWAYS" min_scale="4.5E7" max_scale="0.0" scale_mode="RATIO"/>
<theme name="THEME_DEMO_BIGCITIES" min_scale="" max_scale="0.0" scale_mode="RATIO"/>
<theme name="THEME_DEMO_CITIES" min_scale="7500000.0" max_scale="0.0" scale_mode="RATIO"/>
</map_definition>
Example D-6
Theme Names and Styling Rules for Tile Layer TEST_TL
THEME_DEMO_STATES
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="STATE" name="Name"/>
<field column="STATE_ABRV" name="Abrv."/>
<field column="TOTPOP" name="Population"/>
</hidden_info>
<rule>
<features style="C.S02_COUNTRY_AREA"> </features>
<label column="STATE_ABRV" style="T.S02_STATE_ABBREVS"> 1 </label>
</rule>
</styling_rules>
THEME_DEMO_COUNTIES
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="COUNTY" name="County"/>
<field column="FIPSSTCO" name="Fips"/>
<field column="TOTPOP" name="Population"/>
<field column="STATE_ABRV" name="State"/>
</hidden_info>
<rule>
<features style="L.S06_BORDER_STATE"> </features>
</rule>
D-14
Appendix D
WMTS Operations
</styling_rules>
THEME_DEMO_CITIES
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="CITY" name="City"/>
<field column="POP90" name="Population"/>
</hidden_info>
<rule>
<features style="M.ALL_CITY_L2"> (pop90 between 200000 AND 1000000 ) </featu
res>
<label column="city" style="T.S07_CITIES_L2"> 1 </label>
</rule>
<rule>
<features style="M.ALL_CITY_L3"> (pop90 &lt; 200000) </features>
<label column="city" style="T.S07_CITIES_L3"> 1 </label>
</rule>
</styling_rules>
THEME_DEMO_HIGHWAYS
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="HIGHWAY" name="Name"/>
<field column="ROUTEN" name="No."/>
</hidden_info>
<rule>
<features style="L.S04_ROAD_INTERSTATE"> </features>
<label column="routen" style="M.HWY_USA_INTERSTATE_NARROW"> (3-length(routen
)) </label>
</rule>
</styling_rules>
•
OGC GetFeatureInfo Request
•
MapViewer GetFeatureInfo Request at an (x,y) Point
•
MapViewer GetFeatureInfo Request within a Bounding Box
D.2.3.1 OGC GetFeatureInfo Request
The following is a sample GetFeatureInfo request using the OGC standard (note that
any WMTS request must be on a single line):
http://localhost:8088/mapviewer/wmts?
SERVICE=WMTS&REQUEST=GetFeatureInfo&VERSION=1.0.0&LAYER=MVDEMO:TEST_TL&STYLE=_null&fo
rmat=image/png&TileMatrixSet=MVDEMO:TEST_TL:EPSG:4326&TileMatrix=MVDEMO:TEST_TL:EPSG:
4326:8&TileRow=33&TileCol=76&I=238&J=240&InfoFormat=application/gml%2bxml;
version=3.1
Example D-7 shows the response from this request.
Example D-7
Response from OGC GetFeatureInfo Request
<?xml version="1.0" encoding="UTF-8"?>
<layers>
<layer name="THEME_DEMO_CITIES">
<feature id="1">
<City>Worcester</City>
D-15
Appendix D
WMTS Operations
<Population>169759</Population>
</feature>
</layer>
<layer name="THEME_DEMO_BIGCITIES">
</layer>
<layer name="THEME_DEMO_HIGHWAYS">
</layer>
<layer name="THEME_DEMO_HIGHWAYS_LINE">
</layer>
<layer name="THEME_DEMO_COUNTIES">
<feature id="1">
<County>Worcester</County>
<Fips>25027</Fips>
<Population>709705</Population>
<State>MA</State>
</feature>
</layer>
<layer name="THEME_DEMO_STATES">
<feature id="1">
<State>Massachusetts</State>
<Abrv.>MA</Abrv.>
<Population>6016424</Population>
</feature>
</layer>
</layers>
D.2.3.2 MapViewer GetFeatureInfo Request at an (x,y) Point
The following is a sample MapViewer GetFeatureInfo request for information for all
themes in text/html format at a point identified by its longitude and latitude (x and y)
values, in this case a point in the city of Boston (note that any WMTS request must be
on a single line):
http://localhost:8088/mapviewer/wmts?
SERVICE=WMTS&REQUEST=GetFeatureInfo&VERSION=1.0.0&infoformat=text/
html&LAYER=MVDEMO:TEST_TL&zoomlevel=8&x=-71.01522133879438&y=42.33731136863662&SRID=8
307
In this request, the point's (x,y) coordinates are specified as the parameters.
MapViewer translates the point into a 5 by 5 pixel rectangular area at the given zoom
level (8 in this example), centered at that point, as an area of interest for getting the
feature information. Because there is no childLayer parameter in the request, by
default all features in the area of interest are considered.
If the (x, y) coordinates are in a different coordinate system (spatial reference system)
than that used by the tile layer, then the optional SRID parameter must be specified for
converting the coordinates into the tile layer's system. Its default value is the tile layer's
SRID value.
Figure D-2 shows the response from this request.
D-16
Appendix D
WMTS Operations
Figure D-2
Response from MapViewer GetFeatureInfo Request at an (x,y) Point
D.2.3.3 MapViewer GetFeatureInfo Request within a Bounding Box
The following is a sample MapViewer GetFeatureInfo request for information for two
themes (THEME_DEMO_CITIES and THEME_DEMO_COUNTIES) within an area of
interest defined by a bounding box, in this case a rectangular area including the city of
Boston and some surrounding communities (note that any WMTS request must be on
a single line):
http://localhost:8088/mapviewer/wmts?
SERVICE=WMTS&REQUEST=GetFeatureInfo&VERSION=1.0.0&infoformat=text/
xml&LAYER=MVDEMO:TEST_TL&childLayer=THEME_DEMO_COUNTIES,THEME_DEMO_CITIES&zoomlevel=8
&bbox=-71.32151786220001,42.19361670333521,-70.96354167846667,42.52386233762441&SRID=
8307
If the (x, y) coordinates are in a different coordinate system (spatial reference system)
than that used by the tile layer, then the optional SRID parameter must be specified for
converting the bounding box coordinates into the tile layer's system. Its default value is
the tile layer's SRID value.
Figure D-2 shows the bounding box for this request.
D-17
Appendix D
WMTS Operations
Figure D-3
Bounding Box for MapViewer GetFeatureInfo Request
Example D-8 shows the response in XML format from this request.
Example D-8 Response from MapViewer GetFeatureInfo Request within a
Bounding Box
<layers>
<layer name="THEME_DEMO_CITIES">
<feature id="1">
<City>Boston</City>
<Population>574283</Population>
</feature>
</layer>
<layer name="THEME_DEMO_COUNTIES">
<feature id="1">
<County>Middlesex</County>
<Fips>25017</Fips>
<Population>1398468</Population>
<State>MA</State>
</feature>
<feature id="2">
<County>Norfolk</County>
<Fips>25021</Fips>
<Population>616087</Population>
<State>MA</State>
</feature>
<feature id="3">
<County>Suffolk</County>
<Fips>25025</Fips>
<Population>663906</Population>
<State>MA</State>
</feature>
<feature id="4">
<County>Essex</County>
<Fips>25009</Fips>
<Population>670080</Population>
<State>MA</State>
</feature>
D-18
Appendix D
Preparing the WMTS Service for MapViewer
</layer>
</layers>
D.3 Preparing the WMTS Service for MapViewer
To prepare for using the WMTS Service for MapViewer, follow these major steps:
•
Prepare Predefined Geometry Themes
•
Prepare the Base Map
•
Prepare Tile Layers
•
Publish Tile Layers in the wmtsConfig.xml Policy File
•
Verify the MapViewer WMTS Service
D.3.1 Prepare Predefined Geometry Themes
If the getFeatureInfo service must get feature information from a predefined geometry
theme , you must use the <hidden_info> element with one or more <field> child
elements. The column attribute in the <field> element will be returned in a
getFeatureInfo response.
The <hidden_info> element must be in the <styling_rules> element. For example:
<?xml version="1.0" standalone="yes"?>
<styling_rules>
<hidden_info>
<field column="NAME" name="name"/>
<field column="MAINPAGE" name="mainpage"/>
</hidden_info>
.
.
.
</styling_rules>
For information using styling rules in a predefined geometry theme, see Styling Rules
in Predefined Spatial Geometry Themes
D.3.2 Prepare the Base Map
To prepare a base map (which is just a collection of themes) to use a WMTS theme,
add the theme to the base map.
For information about adding themes to a base map, see Maps.
For information about WMTS themes, see WMTS Themes.
D.3.3 Prepare Tile Layers
A MapViewer tile layer becomes a WMTS layer in the MapViewer WMTS server if
there are no constraints in the wmtsConfix.xml policy file. For example, assume that a
base map named DEMO_MAP has been created as in Example D-2, then tile layers
can be created using that base map. This topic contains the following examples, each
using a well-known scale set found in OGC WMTS 1.0.0 implementation standard
Annex E:
D-19
Appendix D
Preparing the WMTS Service for MapViewer
•
Example D-9
•
Example D-10
•
Example D-11
•
Example D-12
In these examples, the <tile_dpi> and <tile_meters_per_unit> elements are specified,
to comply with the OGC WMTS 1.0.0 implementation standard where pixel size is
0.28mm. If the coordinate (spatial reference) system is WGS84, then 1 degree on the
equator equals 111319.49 meters.
Example D-9
Tile Definition of Scale Set GlobalCRS84Scale
insert into user_sdo_cached_maps values(
'WMTS_E1',
'wmts annex e1 scale set for GlobalCRS84Scale',
'',
'YES',
'YES',
'<map_tile_layer name="WMTS_E1" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3">
<internal_map_source base_map="DEMO_MAP" data_source="MVDEMO" />
<coordinate_system srid="8307" minX="-180" maxX="180" minY="-90" maxY="90"/>
<internal_map_source base_map="DEMO_MAP" data_source="MVDEMO" db_tile_table=""/>
<cache_storage root_path=""/>
<coordinate_system srid="8307" minX="-180" maxX="180" minY="-90" maxY="90"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="21" min_scale="100" max_scale="5.0E8">
<zoom_level scale="5.0E8" tile_width="321.9561978791382" tile_height="321.9561978791382"/>
<zoom_level scale="2.5E8" tile_width="160.9780989395691" tile_height="160.9780989395691"/>
<zoom_level scale="1.0E8" tile_width="64.39123957582764" tile_height="64.39123957582764"/>
<zoom_level scale="5.0E7" tile_width="32.19561978791382" tile_height="32.19561978791382"/>
<zoom_level scale="2.5E7" tile_width="16.09780989395691" tile_height="16.09780989395691"/>
<zoom_level scale="1.0E7" tile_width="6.439123957582764" tile_height="6.439123957582764"/>
<zoom_level scale="5.0E6" tile_width="3.219561978791382" tile_height="3.219561978791382"/>
<zoom_level scale="2.5E6" tile_width="1.609780989395691" tile_height="1.609780989395691"/>
<zoom_level scale="1.0E6" tile_width="0.6439123957582763" tile_height="0.6439123957582763"/>
<zoom_level scale="5.0E5" tile_width="0.32195619787913815" tile_height="0.32195619787913815"/>
<zoom_level scale="2.5E5" tile_width="0.16097809893956908" tile_height="0.16097809893956908"/>
<zoom_level scale="1.0E5" tile_width="0.06439123957582764" tile_height="0.06439123957582764"/>
<zoom_level scale="5.0E4" tile_width="0.03219561978791382" tile_height="0.03219561978791382"/>
<zoom_level scale="2.5E4" tile_width="0.01609780989395691" tile_height="0.01609780989395691"/>
<zoom_level scale="1.0E4" tile_width="0.006439123957582764" tile_height="0.006439123957582764"/>
<zoom_level scale="5.0E3" tile_width="0.003219561978791382" tile_height="0.003219561978791382"/>
<zoom_level scale="2.5E3" tile_width="0.001609780989395691" tile_height="0.001609780989395691"/>
<zoom_level scale="1.0E3" tile_width="6.439123957582763E-4" tile_height="6.439123957582763E-4"/>
<zoom_level scale="5.0E2" tile_width="3.2195619787913813E-4"
tile_height="3.2195619787913813E-4"/>
<zoom_level scale="2.5E2" tile_width="1.6097809893956906E-4"
tile_height="1.6097809893956906E-4"/>
<zoom_level scale="1.0E2" tile_width="6.439123957582763E-5" tile_height="6.439123957582763E-5"/>
</zoom_levels>
</map_tile_layer>',
'DEMO_MAP','');
Example D-10
Tile Definition of Scale Set GlobalCRS84Pixel
insert into user_sdo_cached_maps values(
'WMTS_E2',
D-20
Appendix D
Preparing the WMTS Service for MapViewer
'wmts annex e2 scale GlobalCRS84Pixel',
'',
'YES',
'YES',
'<map_tile_layer name="WMTS_E2" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3">
<internal_map_source base_map="DEMO_MAP" data_source="MVDEMO"/>
<coordinate_system srid="8307" minX="-180" maxX="180" minY="-90" maxY="90"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="1104.360027711047" max_scale="795139219.9519541">
<zoom_level scale="795139219.9519541" tile_width="512.000000" tile_height="512.000000"/>
<zoom_level scale="397569609.9759771" tile_width="256.000000" tile_height="256.000000"/>
<zoom_level scale="198784804.9879885" tile_width="128.000000" tile_height="128.000000"/>
<zoom_level scale="132523203.3253257" tile_width="85.333333" tile_height="85.333333"/>
<zoom_level scale="66261601.66266284" tile_width="42.666666" tile_height="42.666666"/>
<zoom_level scale="33130800.83133142" tile_width="21.333333" tile_height="21.333333"/>
<zoom_level scale="13252320.33253257" tile_width="8.5333333" tile_height="8.5333333"/>
<zoom_level scale="6626160.166266284" tile_width="4.2666666" tile_height="4.2666666"/>
<zoom_level scale="3313080.083133142" tile_width="2.1333333" tile_height="2.1333333"/>
<zoom_level scale="1656540.041566571" tile_width="1.0666666" tile_height="1.0666666"/>
<zoom_level scale="552180.0138555236" tile_width="0.3555555" tile_height="0.3555555"/>
<zoom_level scale="331308.0083133142" tile_width="0.2133333" tile_height="0.2133333"/>
<zoom_level scale="110436.0027711047" tile_width="0.0711111" tile_height="0.0711111"/>
<zoom_level scale="55218.00138555237" tile_width="0.0355555" tile_height="0.0355555"/>
<zoom_level scale="33130.80083133142" tile_width="0.0213333" tile_height="0.0213333"/>
<zoom_level scale="11043.60027711047" tile_width="0.00711111" tile_height="0.00711111"/>
<zoom_level scale="3313.080083133142" tile_width="0.00213333" tile_height="0.00213333"/>
<zoom_level scale="1104.360027711047" tile_width="7.111111E-4" tile_height="7.111111E-4"/>
</zoom_levels>
</map_tile_layer>',
'DEMO_MAP',
'');
Example D-11
Tile Definition of Scale Set GoogleCRS84Quad
insert into user_sdo_cached_maps values(
'WMTS_E3',
'wmts annex e3 scale set GoogleCRS84Quad',
'',
'YES',
'YES',
'<map_tile_layer name="WMTS_E3" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3">
<internal_map_source base_map="DEMO_MAP" data_source="MVDEMO"/>
<coordinate_system srid="8307" minX="-180" maxX="180" minY="-90" maxY="90"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="111319.49079327358"/>
<zoom_levels levels="19" min_scale="2132.729583849784" max_scale="559082264.0287178">
<zoom_level tile_width="360.0000" tile_height="360.0000" scale="5.590822640287178E8"/>
<zoom_level tile_width="180.0000" tile_height="180.0000" scale="2.795411320143589E8"/>
<zoom_level tile_width="90.0000" tile_height="90.00000" scale="1.3977056600717944E8"/>
<zoom_level tile_width="45.0000" tile_height="45.00000" scale="6.988528300358972E7"/>
<zoom_level tile_width="22.5000" tile_height="22.50000" scale="3.494264150179486E7"/>
<zoom_level tile_width="11.2500" tile_height="11.25000" scale="1.747132075089743E7"/>
<zoom_level tile_width="5.6250" tile_height="5.62500" scale="8735660.375448715"/>
<zoom_level tile_width="2.8125" tile_height="2.81250" scale="4367830.1877243575"/>
<zoom_level tile_width="1.40625" tile_height="1.40625" scale="2183915.0938621787"/>
<zoom_level tile_width="0.703125" tile_height="0.703125" scale="1091957.5469310894"/>
D-21
Appendix D
Preparing the WMTS Service for MapViewer
<zoom_level tile_width="0.3515625" tile_height="0.3515625" scale="545978.7734655447"/>
<zoom_level tile_width="0.17578125" tile_height="0.17578125" scale="272989.38673277234"/>
<zoom_level tile_width="0.087890625" tile_height="0.087890625" scale="136494.693366386"/>
<zoom_level tile_width="0.0439453125" tile_height="0.0439453125" scale="68247.34668319"/>
<zoom_level tile_width="0.02197265625" tile_height="0.02197265625" scale="34123.6733415"/>
<zoom_level tile_width="0.010986328126" tile_height="0.010986328126" scale="17061.8366707"/>
<zoom_level tile_width="0.0054931640633" tile_height="0.0054931640633" scale="8530.91833539"/>
<zoom_level tile_width="0.00274658203168" tile_height="0.00274658203168" scale="4265.45916769"/>
<zoom_level tile_width="0.001373291015841" tile_height="0.001373291015841"
scale="2132.72958384"/>
</zoom_levels>
</map_tile_layer>',
'DEMO_MAP',
'');
Example D-12
Tile Definition of Scale Set GoogleMapsCompatible
insert into user_sdo_cached_maps values(
'WMTS_E4',
'wmts annex e4 scale set',
'',
'YES',
'YES',
'<map_tile_layer name="WMTS_E4" image_format="PNG" http_header_expires="168.0"
concurrent_fetching_threads="3">
<internal_map_source base_map="DEMO_MAP" data_source="MVDEMO"/>
<coordinate_system srid="3857" minX="-20037508" maxX="20037508" minY="-20037508"
maxY="20037508"/>
<tile_image width="256" height="256"/>
<tile_dpi value="90.7142857"/>
<tile_meters_per_unit value="1"/>
<zoom_levels levels="19" min_scale="2132.729583849784" max_scale=" 559082264.0287178">
<zoom_level tile_width="4.0075016692E7" tile_height="4.0075016692E7" scale="5.5908226403E8"/>
<zoom_level tile_width="2.0037508346E7" tile_height="2.0037508346E7" scale="2.7954113201E8"/>
<zoom_level tile_width="1.0018754173E7" tile_height="1.0018754173E7" scale="1.3977056601E8"/>
<zoom_level tile_width="5009377.086486" tile_height="5009377.086486" scale="6.9885283004E7"/>
<zoom_level tile_width="2504688.543243" tile_height="2504688.543243" scale="3.4942641502E7"/>
<zoom_level tile_width="1252344.27162" tile_height="1252344.27162" scale="1.747132075089E7"/>
<zoom_level tile_width="626172.135810" tile_height="626172.135810" scale="8735660.3754487"/>
<zoom_level tile_width="313086.067905" tile_height="313086.067905" scale="4367830.1877243"/>
<zoom_level tile_width="156543.033952" tile_height="156543.033952" scale="2183915.0938621"/>
<zoom_level tile_width="78271.5169763" tile_height="78271.5169763" scale="1091957.5469311"/>
<zoom_level tile_width="39135.7584882" tile_height="39135.7584882" scale="545978.77346554"/>
<zoom_level tile_width="19567.8792441" tile_height="19567.8792441" scale="272989.38673277"/>
<zoom_level tile_width="9783.93962204" tile_height="9783.93962204" scale="136494.69336638"/>
<zoom_level tile_width="4891.96981102" tile_height="4891.96981102" scale="68247.346683193"/>
<zoom_level tile_width="2445.98490551" tile_height="2445.98490551" scale="34123.673341596"/>
<zoom_level tile_width="1222.99245275" tile_height="1222.99245275" scale="17061.836670798"/>
<zoom_level tile_width="611.496226378" tile_height="611.496226378" scale="8530.9183353991"/>
<zoom_level tile_width="305.748113189" tile_height="305.748113189" scale="4265.4591676995"/>
<zoom_level tile_width="152.874056594" tile_height="152.874056594" scale="2132.7295838498"/>
</zoom_levels>
</map_tile_layer>',
'DEMO_MAP',
'');
D.3.4 Publish Tile Layers in the wmtsConfig.xml Policy File
To publish tile layers, you can edit and add information in the <public_datasources>
element in the wmtsConfig.xml policy file, which is stored in the same location as
D-22
Appendix D
Preparing the WMTS Service for MapViewer
mapViewerConfig.xml. Example D-13 shows the entries for publishing five tiles in data
source MVDEMO (TEST_EL, WMTS_E1, WMTS_E2, WMTS_E3, and WMTS_E4)
and all tile layers in data source TILSMENV.
Example D-13
Publishing Tile Layers
<public_datasources>
<public_datasource name="MVDEMO">
<tile_layers>
<tile_layer name="TEST_TL"/>
<tile_layer name="WMTS_E1"/>
<tile_layer name="WMTS_E2"/>
<tile_layer name="WMTS_E3"/>
<tile_layer name="WMTS_E4"/>
</tile_layers>
</public_datasource>
<public_datasource name="TILSMENV" include_all_tile_layers="TRUE">
</public_datasources>
D.3.5 Verify the MapViewer WMTS Service
To verify that the MapViewer WMTS service is working properly, follow these steps:
1.
Restart the MapViewer server to let MapViewer retrieve the tile layer definitions
from the data source and apply the WMTS policy file.
2.
Issue a GetCapabilities request in the following format, to check that the tile layers
are published and that all scale sets are shown as expected:
http://<url>:<port>/mapviewer/wmts?
REQUEST=GetCapabilities&SERVICE=WMTS&VERSION=1.0.0
D-23
Index
A
accelerator keys
for Map Builder tool menus, 5-3
adding themes to a map, 2-78
advanced style, 2-2
thematic mapping and, 2-68
XML format for defining, A-9
ALL_SDO_CACHED_MAPS view, 2-97
ALL_SDO_MAPS view, 2-93, 2-97
ALL_SDO_STYLES view, 2-93, 2-95
ALL_SDO_THEMES view, 2-93, 2-96
allow_jdbc_theme_based_foi attribute, 1-23
allow_local_adjustment attribute, 1-15
annotation text themes, 2-61
APIs
JavaScript for Oracle Maps, 4-1
MapViewer XML
adding a WMS map theme, C-13
appearance
attributes affecting theme appearance, 2-77
area style, 2-2
XML format for defining, A-8
authentication
WMS map themes, C-16
auto-update of cached map tiles, 3-30
automatic legends, 2-82
AWT headless mode support, 1-4
azimuthal equidistant projection
used for globular map projection, 1-15
B
background color
for WMS requests, C-5
bar chart marker style
XML format for defining, A-14
base maps, 2-78
definition (example), 2-79
for WMS requests, C-4
XML format, A-1
XML format for defining, A-23
BASEMAP parameter (WMS), C-4
BBOX parameter (WMS), C-5
BGCOLOR parameter (WMS), C-5
binding parameters, 2-16
Bing Maps
built-in map tile layers, 4-7
transforming data to the Microsoft Bing Maps
coordinate system, 4-9
bitmap masks
with GeoRaster themes, 2-35
bounding box
for WMS requests, C-5
bucket style
specifying labels for buckets, 2-5
XML format for defining, A-10
built-in map tile layers, 4-7
C
cache
auto-update of cached map tiles, 3-30
metadata, 2-85
spatial data, 1-16
with predefined themes, 2-18
caching attribute
for predefined theme, 2-18, A-21
catalog data sources, 2-86
classgen.jar file, C-2
cluster
deploying map visualization component on
middle-tier cluster, 1-33
collection bucket style
with discrete values, A-11
collection style
XML format for defining, A-15, A-16
color scheme style
XML format for defining, A-12
color stops (heat map), A-16
color style, 2-2
XML format for defining, A-2
container data source, 1-23
container theme name (heat map), A-16
container_ds attribute, 1-23
container-controlled logging, 1-12
cookie
getting authenticated user’s name from, 1-37
coordinate system, 2-78
cross-schema map requests, 2-90
Index-1
Index
custom spatial provider
creating and registering, B-1
s_data_provider element, 1-18
D
data providers
nonspatial, 1-18
data sources
catalog, 2-86
container_ds attribute, 1-23
explanation of, 2-85
for WMS requests, C-5
DATASOURCE parameter (WMS), C-5
DBA_SDO_STYLES view, 2-95
debug mode
topology themes, 2-43
decorative aspects
attributes affecting theme appearance, 2-77
dirty cached map tiles, 3-30
dirty_tile_auto_update element, 3-30
dot density marker style
XML format for defining, A-14
dynamic tile layers, 4-11
DYNAMIC_STYLES parameter (WMS), C-5
dynamically defined styles, 2-3
for WMS requests, C-5
dynamically defined themes, 2-22
E
EPSG
in SRS parameter (WMS), C-7
EXCEPTIONS parameter (WMS)
for GetFeatureInfo request, C-11
for GetMap request, C-5
external attribute data, 2-74
F
feature labels
support for translation, 2-19
FEATURE_COUNT parameter (WMS), C-11
features of interest (FOIs)
allow_jdbc_theme_based_foi attribute, 1-23
field element
for hidden information, A-22
FOIs
allow_jdbc_theme_based_foi attribute, 1-23
FORMAT parameter (WMS), C-5
G
geodetic data
geodetic data (continued)
projecting to local non-geodetic coordinate
system, 1-15
GeoRaster themes, 2-28
bitmap masks, 2-35
reprojection, 2-36
setting polygon mask, 2-29
theme_type attribute in styling rules, A-20
GetCapabilities request and response, C-7
GetFeatureInfo request
specifying attributes to be queried, C-12
supported features, C-10
GetMap request
parameters, C-3
globular map projection, 1-15
Google Maps
built-in map tile layers, 4-7
transforming data to the Google Maps
coordinate system, 4-9
grid sample factor (heat map), A-16
GridLink data source, 1-27
H
headless AWT mode support, 1-4
heat map style
XML format for defining, A-16
HEIGHT parameter (WMS), C-6
hidden information (SVG maps)
hidden_info element, A-22
hidden_info element, A-22
high availability
using map visualization component with,
1-33
I
image format
for WMS requests, C-5
image marker style
XML format for defining, A-5
image themes, 2-26
theme_type attribute in styling rules, A-20
images
getting sample image for a style, 2-9
INFO_FORMAT parameter (WMS), C-11
internationalization
translation of feature labels, 2-19
J
JavaScript API for Oracle Maps, 4-1
JDBC theme-based features of interest, 1-23
JDBC themes, 2-22
Index-2
Index
JDBC themes (continued)
saving complex SQL queries, 2-25
join view
key_column styling rule attribute required for
theme defined on join view, A-21
K
key_column attribute
for theme defined on a join view, A-21
L
label attribute, 2-70
label_max_scale attribute, 2-80
label_min_scale attribute, 2-80
labeling of spatial features, 2-14
label styles for individual buckets, 2-5
primary and secondary labels, 2-22
translation of feature labels, 2-19
LAYERS parameter (WMS), C-6
legend, 2-81
automatic, 2-82
example, 2-81
for WMS requests, C-6
LEGEND_REQUEST parameter (WMS), C-6
line style, 2-2
XML format for defining, A-6
Linear Referencing System (LRS) themes, 2-65
load balancer
using map visualization component with,
1-34
local geodetic data adjustment
specifying for map, 1-15
logging element, 1-12
logging information, 1-12
container-controlled, 1-12
logo
specifying for map, 1-14
longitude/latitude coordinate system, 2-78
LRS (Linear Referencing System) themes, 2-65
M
Map Builder tool, 5-1
running, 5-1
user interface (UI), 5-2
map cache auto-update, 3-30
map data server, 3-1
Map Data Server (MDS), 1-24
map image file information, 1-13
map legend, 2-81
example, 2-81
map logo, 1-14
map note, 1-14
map rendering, 1-34
map requests
cross-schema, 2-90
map tile layers
built-in, 4-7
XML format for defining, A-24
map tile server, 3-12
configuring, 1-21
map title, 1-14
map visualization component
configuration file sample, 1-5
map data server, 3-1
map tile server, 3-12
prerequisite software, 1-3
servers, 3-1
map_tile_server element, 1-21
mapbuilder.jar file, 5-1
mapdefinition.sql file, 2-94
mappers (renderers), 2-85
number of, 1-23
mapping profile, 2-2
maps, 1-34, 2-78
creating by adding themes and rendering,
2-78
explanation of, 2-79
how they are generated, 2-88
metadata view, 2-93
scale, 2-79
size, 2-79
mapViewerConfig.xml configuration file
sample, 1-5
marker style, 2-2
orienting, 2-8
using on lines, A-5
XML format for defining, A-3
masks
bitmap (GeoRaster themes), 2-35
max_scale attribute, 2-80
MDS (Map Data Server), 1-24
mds.xml file, 1-24
metadata cache, 2-85
metadata views, 2-93
mapdefinition.sql file, 2-94
Microsoft Bing Maps
built-in map tile layers, 4-7
transforming data to the Microsoft Bing Maps
coordinate system, 4-9
middle-tier cluster
deploying map visualization component on,
1-33
min_scale attribute, 2-80
Multi data source, 1-29
MVTHEMES parameter (WMS), C-6
3
Index
N
predefined themes, 2-12
caching of, 2-18
LAYERS parameter (WMS), C-6
WMS map, C-16
prerequisite software for using map visualization
component, 1-3
primary labels
linear features, 2-22
projection of geodetic data to local non-geodetic
coordinate system, 1-15
network analysis
shortest-path, 2-41
within-cost, 2-42
network themes, 2-38
theme_type attribute in styling rules, A-20
networked drives
using map visualization component with,
1-34
nonspatial data provider, 2-74
nonspatial data providers
registering, 1-18
note
specifying for map, 1-14
ns_data_provider element, 1-18
number_of_mappers attribute, 1-23, 2-85
query type
for WMS requests, C-12
QUERY_LAYERS parameter (WMS), C-12
QUERY_TYPE parameter (WMS), C-12
O
R
OGC (Open GIS Consortium)
WMS support by map visualization
component, C-1
WMTS support by map visualization
component, D-1
omserver (in URL)
getting a sample image of a style, 2-10
Open GIS Consortium
WMS support by map visualization
component, C-1
WMTS support by map visualization
component, D-1
Oracle Map Builder tool, 5-1
Oracle Maps, 2-98, 4-1
JavaScript API, 4-1
map tile server, 3-12
Oracle Real Application Clusters (RAC)
using map visualization component with,
1-27
orientation vector
using with an oriented point, 2-7
oriented points
pointing label or marker in direction of
orientation vector, 2-7
out-of-bounds color (tile), 3-19
overlapping text style, 2-11
RAC (Oracle Real Application Clusters)
using map visualization component with,
1-27
radius
for WMS requests, C-12
RADIUS parameter (WMS), C-12
Real Application Clusters (Oracle RAC)
using map visualization component with,
1-27
redlining, 4-1
renderers (mappers), 2-85
number_of_mappers attribute, 1-23
rendering a map, 2-78
secure map rendering, 1-34
rendering styles
with scale ranges, 2-18
reprojection
with GeoRaster themes, 2-36
REQUEST parameter (WMS)
GetMap or GetCapabilities, C-6
required software for using map visualization
component, 1-3
rules
styling, 2-13
P
sample image
getting for a style, 2-9
save_images_at element, 1-13
scalable styles, 2-4
scale of map, 2-79
scale ranges
with rendering styles, 2-18
parameters
binding, 2-16
plsql_package attribute, 1-24
polygon mask
setting for GeoRaster theme, 2-29
polygon_mask attribute, 2-29
Q
S
Index-4
Index
secondary labels
linear features, 2-22
secure, 1-34
secure map rendering, 1-34
plsql_package attribute, 1-24
web_user_type attribute, 1-24
secure rendering, 1-34
security
security_config element, 1-16
security_config element, 1-16
seq attribute, 2-70
SERVICE parameter (WMS), C-6
shortcut keys
for Map Builder tool menus, 5-3
shortest-path analysis, 2-41
size of map, 2-79
spatial data cache
customizing, 1-16
spatial data provider
custom, 1-18
spatial_data_cache element, 1-16
spot light radius (heat map), A-17
SRS mapping
customizing, 1-19
SRS parameter (WMS), C-7
srs_mapping element, 1-19
sticky attribute for text style, 2-9
styles, 2-2
advanced, 2-2
thematic mapping and, 2-68
XML format for defining, A-9
allowing text style overlapping, 2-11
area, 2-2
XML format for defining, A-8
bar chart
XML format for defining, A-14
bucket
specifying labels for buckets, 2-5
XML format for defining, A-10
collection
XML format for defining, A-15, A-16
color, 2-2
XML format for defining, A-2
color scheme
XML format for defining, A-12
dot density
XML format for defining, A-14
dynamically defined, 2-3
getting sample image, 2-9
heat map
XML format for defining, A-16
image marker
XML format for defining, A-5
label styles for buckets, 2-5
line, 2-2
styles (continued)
line (continued)
XML format for defining, A-6
marker, 2-2
XML format for defining, A-3
metadata view, 2-93
scaling size of, 2-4
text, 2-2
XML format for defining, A-8
TrueType font-based marker
XML format for defining, A-5
variable marker
XML format for defining, A-13
vector marker
XML format for defining, A-4
XML format, A-1
STYLES parameter (WMS), C-7
styling rules, 2-13, A-1
XML format for specifying, A-18
T
templated themes, 2-16
temporary styles
See dynamically defined styles
text style, 2-2
orienting, 2-7
sticky attribute, 2-9
XML format for defining, A-8
thematic mapping, 2-68
using external attribute data, 2-74
theme_type attribute
for certain types of predefined themes, A-20
themes, 2-11
adding to a map, 2-78
annotation text, 2-61
attributes affecting appearance, 2-77
dynamically defined, 2-22
for WMS requests, C-6
GeoRaster, 2-28
setting polygon mask, 2-29
theme_type attribute in styling rules,
A-20
image, 2-26
theme_type attribute in styling rules,
A-20
JDBC, 2-22
LRS (Linear Referencing System), 2-65
metadata view, 2-93
network, 2-38
theme_type attribute in styling rules,
A-20
predefined, 2-12
setting GeoRaster theme polygon mask, 2-29
styling rules, A-18
5
Index
themes (continued)
templated, 2-16
topology, 2-42
debug mode, 2-43
theme_type attribute in styling rules,
A-20
virtual mosaic, 2-36
WFS, 2-45
WMS map
adding, C-13
adding (XML API), C-13
authentication with, C-16
WMTS, 2-49
Workspace Manager support, 2-92
XML format, A-1
tile background color, 3-19
tile layers
dynamic, 4-11
tile out-of-bounds color, 3-19
tile server (map visualization component), 3-12
title
specifying for map, 1-14
topology themes, 2-42
debug mode, 2-43
theme_type attribute in styling rules, A-20
translation
of feature labels, 2-19
TRANSPARENT parameter (WMS)
supported for PNG format, C-7
TrueType font-based marker style
XML format for defining, A-5
U
unit of measurement
for WMS requests, C-12
UNIT parameter (WMS), C-12
use_globular_projection option, 1-15
USER_SDO_CACHED_MAPS view, 2-97
USER_SDO_GEOM_METADATA view
entry for predefined theme based on a view,
2-12
inserting row into, 2-12
USER_SDO_MAPS view, 2-93, 2-97
USER_SDO_STYLES view, 2-93, 2-95
USER_SDO_THEMES view, 2-93, 2-96
USER_SDO_TILE_ADMIN_TASKS view, 2-94
V
variable marker style
XML format for defining, A-13
vector marker style
XML format for defining, A-4
VERSION parameter (WMS), C-7
views
key_column styling rule attribute required for
theme defined on join view, A-21
metadata, 2-93
virtual mosaic themes, 2-36
W
Web Map Service (WMS) protocol, C-1
adding a WMS map theme, C-13
setting up for MapViewer, C-1
See also entries starting with "WMS"
Web Map Service (WMTS) protocol, D-1
See also entries starting with "WMTS"
Web Map Tile Service (WMTS) protocol, D-1
web_user_type attribute, 1-24
WFS themes, 2-45
WGS 84 coordinate system, 2-78
WIDTH parameter (WMS), C-7
within-cost analysis, 2-42
WMS Capabilities responses
customizing, 1-19
WMS data source
default for GetMap requests, C-3
WMS map themes
adding, C-13
XML API, C-13
authentication with, C-16
predefined, C-16
wms_config element, 1-19
wms_getmap_request element, C-13
WMSFilter.jar file, C-2
WMTS Capabilities responses
customizing, 1-20
WMTS themes, 2-49
wmts_config element, 1-20
Workspace Manager
support in map visualization component, 2-92
workspace_name attribute, 2-92
workspace_savepoint attribute, 2-92
X
X parameter (WMS), C-12
X11 DISPLAY variable
no need to set when using AWT headless
mode, 1-4
XML
format for base maps, map tile layers
XML format, A-1
format for map tile layers, A-1
format for styles, A-1
format for themes, A-1
xmlparserv2.jar file, C-2
Index-6
Index
Y
Y parameter (WMS), C-12
7
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