PixarAnimationStudios/OpenSubdiv — pull request #308 by nathan-at-digitalfish (2014-05-28 20:57:58+00:00)
Title: New face vertex kernels

Added the `CATMARK_QUAD_FACE_VERTEX` and `CATMARK_TRI_QUAD_FACE_VERTEX` kernels.

* The `CATMARK_QUAD_FACE_VERTEX` kernel calculates the face-vertex for a quadrilateral face. It applies to every face after the first subdivision step, and may be applied for the first subdivision step of a quadrilateral coarse mesh.

* The `CATMARK_TRI_QUAD_FACE_VERTEX` kernel calculates the face-vertex for a triangle or quadrilateral face. It may be applied for the first subdivision step of a coarse mesh composed of triangles and/or quadrilaterals.

* Both kernels calculate each face-vertex using four vertex indices (triangles are specified by repeating the third index). Therefore neither kernel uses the `F_ITa` codex table, and instead the first vertex offset in the `F_IT` index table is stored in the `FarKernelBatch`'s table offset.