Subdividing

I wanted to render primarily with RenderMan for Maya because of its stability, efficiency, sub-pixel tessellation and its high-quality raytracing. I was modeling everything in polygons and subdividing at render time, so that everything could remain easily modifiable in case I needed to make any changes.

Here’s how I went through the process.

1. In the RenderMan tab, click on the “SGA menu” (Shared Geometric Attributes) button. A dialogue window pops up. Click “Create” and then, with the newly created “rmanSettings” attribute selected, click “Edit.”


2. In the Attribute Editor, click Attributes > RenderMan > Manage Attributes…



3. Another dialogue window pops up with a list of attributes. You want to scroll down to “Subdivision Scheme” and click “Add.”


4. Notice that you now have Extra RenderMan Attributes in your Attribute Editor. Click the triangle to expand them. You’ll see your Subdivision Scheme there. You’ve got three options: Catmull-Clark (better for subdividing quads), Loop (better for triangles) and None. Since I modeled everything with quads, I used Catmull-Clark. I’ve also renamed my attribute to “brian_subD.”

5. We now want to assign our custom RenderMan Attribute to some geometry. Select your polygon objects to be subdivided, and in your SGA menu, select “brian_SubD.” Click attach.

6. When you render with RenderMan, your geometry will be subdivided.
See Also:
Subdivision Surfaces (Wikipedia)
NURBS (Wikipedia)