G I F T S

Mental Ray

The Shadow-Separator material/light shader ...

This mental ray shader makes a material visible only where it receives shadow cast from particular lights. It can also make a material invisible where the shadow falls (so where the shadow appears, there's a hole.)

When you download the shader, (it's actually in the form of a shader library called VSHADERS, in VSHADERS.tar.Z,) just add the appropriate entries in your DatabaseDir.rsrc file, eg.

   DATABASE VSHADERS
   PATH /your/path/VSHADERS
   TYPE SHADERLIB

When using the shader, click on "Info" for a more detailed description.

About the example flipbook:

The scene consists of one strutting skeleton, one raytrace point light, and one default grid. The skeleton and camera are animated, the grid and light are static.

The grid is behind the skeleton and has a default material accompanied with the Shadow-Separator material shader (with its default parameters). On the grid there's a 2D texture map from the Softimage SI_Materials library (with default 2D texture parameters).

The light is a default point light with raytraced shadows turned on and the Shadow-Separator light shader attached to it (no parameters).

What you see in the rendered flipbook is the skeleton and its shadow on the grid. The grid is only visible where the shadow falls. The shadow grows in size as the skeleton struts further from the light.

SGI movie flipbook (2.9M)
Quick Time flipbook (2.5M)

Vincent Lu
SOFTIMAGE Developer Support
vincent.lu@softimage.com

GIFTS