Link light sources to surfaces to control shadow calculations

Use shadow linking to link light sources with surfaces so that selected objects only cast shadows from light sources with which they are linked. This technique is similar to light linking except that it controls shadow calculations rather than illumination calculations.

Refer to the following links for descriptions on how to create or break shadow links between lights and surfaces:

• To link selected lights to surfaces using shadow linking (Maya software renderer)
• To link selected lights to surfaces using shadow linking (Maya Hardware renderer)
• To break links between lights and surfaces using shadow linking (Maya software renderer)
• To break links between lights and surfaces using shadow linking (Maya Hardware renderer)

  Tips:

  • You can select multiple lights and multiple surfaces when making and breaking shadow links.
  • The shadows in your scene can obey only one of light linking or shadow linking and not both. Therefore, for the purpose of shadows, you must decide whether to incorporate light linking or shadow linking in your scene.
  • The Shadows Ignore Linking option is available via the Render Settings window. This option specifies that all objects are shadow casters and any light or shadow links are ignored for shadow calculations. See Shadow linking for more information.

To link selected lights to surfaces using shadow linking (if rendering with Maya Software renderer)

1. Select the lights and surfaces you want to link.
2. In the Rendering menu set, select Lighting/shading > Make Shadow Links.
3. When rendering with Maya Software, you may render shadow links via raytraced shadows or depth mapped shadows.
   • If you render via raytraced shadows, click on each light source and select Use Ray Trace Shadows in the light’s Attribute Editor. In the Render Settings window, enable Raytracing.
   • If you render via depth map shadows, click on each light source and select Use Depth Map Shadows in the light’s Attribute Editor. In the Render Settings Window, check Enable Depth Maps.
4. In the Render Settings window, click on the Maya Software tab and expand the Render Options section to see the Lights and Shadows attributes. Set Shadow linking to Shadows obey shadow linking.

To link selected lights to surfaces using shadow linking (if rendering with Maya Hardware)

1. Select the lights and surfaces you want to link.
2. In the Rendering menu set, select Lighting/shading > Make Shadow Links.
3. When rendering with Maya Hardware, shadow linking must be used in conjunction with depth map shadows. Click on each light source and select Use Depth Map Shadows in the light’s Attribute Editor.
4. In the Render Settings window, click on the Maya Hardware tab and expand the Render Options section to see the Shadow linking option. Set Shadow linking to Shadows obey shadow linking.

To break links between lights and surfaces using shadow linking (if rendering with Maya Software renderer)

1. Select the lights and surfaces you want to link.
2. In the Rendering menu set, select Lighting/shading > Break Shadow Links.
3. When rendering with Maya Software, you may render shadow links via raytraced shadows or depth mapped shadows.
   • If you render via raytraced shadows, click on each light source and select Use Ray Trace Shadows in the light’s Attribute Editor. In the Render Settings window, enable Raytracing.
   • If you render via depth map shadows, click on each light source and select Use Depth Map Shadows in the light’s Attribute Editor. In the Render Settings Window, check Enable Depth Maps.
4. In the Render Settings window, click on theMaya Software tab and expand the Render Options section to see the Lights and Shadows attributes. Set Shadow linking to Shadows obey shadow linking.

To break links between lights and surfaces using shadow linking (if rendering with Maya Hardware)

1. Select the lights and surfaces you want to link.
2. In the Rendering menu set, select Lighting/shading > Break Shadow Links.
3. When rendering with Maya Hardware, then shadow linking must be used in conjunction with depth map shadows. Click on each light source and select Use Depth Map Shadows in the light’s Attribute Editor.
4. In the Render Settings window, click on the Maya Hardware tab and expand the Render Options section to see the Shadow linking option. Set Shadow linking to Shadows obey shadow linking.