Occlusion in RenderMan by Gustavo Braga
- Gustavo Braga the beta tester for Maya 3d has published his test and their results on his blog about the "Occlusion in RenderMan" . RenderMan is a widely used render plug-in for Alias Maya 3d..............Gustavo; What we call occlusion is an aproximation from the diffuse contact shadow computation. This estimative is done calculating how much the hemisphere above a point is covered by other objects. In RenderMan we can calculate the occlusion in two ways: using a "gather loop" or a predefined function called "occlusion".The first shader, occlgather.sl, uses a gather loop. To each shading point it projects rays (quantity specified in the samples attribute) in random directions in the hemisphere. For each ray that hits an object the variable hits is incremented. After the loop, the occlusion is calculated by dividing the hits by samples. As the number of rays increases (samples), more quality you get (less noise), but the rendering time........................Read On !!
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Read About 3d Artist Gustavo Braga
Tags: Maya 3d . RenderMan . Global Illumination . 3d Plug-ins