Lightscape User Guide

Setting the Surface Processing Parameters

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The wizard dialog appears.

3.

Choose a level of quality on the Quality page, then click Next.

4.

On the Daylight page, choose whether to consider daylight in your solution.

5.

7.

If you chose No, click Next.

6.

If you chose Yes, select the statement that describes your model, then click Next.

On the Finish Wizard page, click Finish.

The meshing parameters for the model are set automatically.

8.

Click OK.

complete radiosity solution, you must reset the solution and start again.

Enable:

Occluding

Receiving

Reflecting

Window

Opening

Display Raw

Textures

No Mesh

To:

Block light and cast a shadow with the surface.

Receive light on the surface.

Reflect light back into the environment from the surface.

Define a window with the surface.

Define an opening with the surface.

Prevent the calculation of lighting effects on the surface’s texture.

Prevent mesh subdivision on the surface.

To set the surface processing parameters:

1.

On your model, select the surface (or surfaces) whose processing parameters you want to set.

2.

Right-click and choose Surface Processing.

The Surface Processing dialog appears.

Setting the Surface Processing

Parameters

The surface processing parameters affect the processing of a surface or group of surfaces. Use these parameters to fine-tune the radiosity process, maximizing quality while minimizing computation time and storage requirements.

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If you change any of these parameters after processing has begun, they are considered only for the iterations run after the change. To affect the

3.

Enable the surface processing options, as required.

4.

To adjust the Mesh Resolution parameter, enter a value in the box, adjust the slider, or click the Mesh

Resolution increments buttons.

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11 Radiosity Processing

5.

To reset the radiosity mesh (once processing has begun), click the Reset Mesh button.

6.

Click OK.

Occluding

Use Occluding to control whether or not a surface blocks light. Enable this option to cause a surface to cast a shadow; disable this option to cause light to pass straight through it unaffected.

Surfaces are occluding by default.

Receiving

Use Receiving to control whether light reaching the surface is recorded in its radiosity mesh. Surfaces are receiving by default.

When disabled, this option saves computation time on a self-emitting surface. The initial luminance of such a surface may be much larger than the illumination incident. For more information, see “Making a

Material Self-Illuminating” on page 114.

Reflecting

Use Reflecting to control whether a surface should reflect incident light back into the environment.

Surfaces are reflecting by default.

One useful application of this feature is in lighting analysis. You can disable the Occluding and

Reflecting properties of a surface and place the surface anywhere in a scene to measure the illumination incident without otherwise affecting the illumination of the scene.For more information, see

“Using Workplanes” on page 200.

Note: When using IES photometric distributions in luminaires, you should set the surfaces of the luminaire to be nonreflecting so that energy is not emitted twice.

Window

Use Window to control whether a surface is considered a window and treated as a source during natural lighting computations. You must give the window a transparent material so that natural lighting can pass through it.

Opening

Use Opening in a similar way as Window. When a surface is defined as an opening, it is not considered as part of the scene and does not receive or reflect light. Instead, it is used as a placeholder to indicate that natural lighting can pass through it to reach the surfaces of an interior environment. Surfaces defined as openings are not rendered and are not displayed in the model.

Display Raw Textures

Use Display Raw Textures to control whether a texture is displayed with lighting from the radiosity solution. Use this parameter for surfaces with textures on which you performed the mesh-totexture conversion and now have lighting information embedded in the texture itself. Enabling the

Display Raw Textures parameter tells Lightscape not to relight the texture. You can also use this parameter for any surfaces on which you do not want Lightscape to calculate lighting effects.

Mesh Resolution

Use Mesh Resolution to improve the quality of a radiosity solution without significantly affecting its cost. Meshing artifacts in a radiosity solution often appear on only a few surfaces in the scene. Rather than trying to eliminate the problem by changing the global meshing parameters, it may be more efficient to adjust the meshing controls on the individual problem surfaces.

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