The Light Attribute Node is used to specify parameters that are not contained in the light shader. For instance, several light shaders can use shadow maps; the Light Attribute Node can be used to generate these shadow maps. When there are no light attribute node attached to a light, 3Delight for Maya will do its best to extract relevant parameters from the Maya light node.
Light Attribute nodes are created empty. Attributes can be added and removed by using the Add / Remove Attributes button. Left-click on this button brings up the Add / Remove Attributes Window, which is better suited for multiple attribute addition or removal (see The Add / Remove Attributes Window). Right-click on the Add / Remove Attributes button offers the same functionality through popup menus, which are more convenient when only one attribute or attribute group needs to be added or removed.
MEL Scripts
3Delight For Maya lets you run MEL scripts before and after each shadow map.
Pre Render MEL
This attribute specify a MEL script that will be executed before the shadow map is rendered. More precisely, the script will be executed just before the FrameBegin RIB statement of the shadow map. This attribute is empty by default.
Post Render MEL
This attribute specify a MEL script that will be executed after the shadow map is rendered. More precisely, the script will be executed just after the FrameEnd RIB statement of the shadow map. This attribute is empty by default.
Two variables are automatically defined in the execution scripts execution as show in the following table.
| Variable | Description |
|---|---|
string $shape_path | Contains the current light shape path. |
string $attribs_node | Contains the current light attribute node name. |