abstract
We present a fast algorithm for converting quad meshes on the GPU to smooth surfaces.
Meshes with 12,000 input quads, of which 60% have one or more non-4-valent vertices,
are converted, evaluated and rendered with 9×9 resolution per quad at 50 frames per second.
The conversion reproduces bi-cubic splines wherever possible and closely mimics
the shape of the Catmull-Clark subdivision surface by c-patches where a vertex
has a valence different from 4. The smooth surface is piecewise polynomial and
has well-defined normals everywhere. The evaluation avoids pixel dropout.