Subdivision

Imagine has had support for Catmull-Clark subdivision of quads within its interface for a while now, but the previous implementation had several limitations: it was slow and memory-inefficient (it just brute-forced the subdivision from the original faces), it didn’t support open shapes with holes and it didn’t keep UVs.

I’ve now re-written this to use a half-edge mesh structure, which makes it faster (less duplicate work is done), it supports boundary edges (holes in geometry), supports triangles and it subdivides UV positions (linearly at preset). I’ve also added support for linear subdivision with no smoothing.

Once I sort out the Geometry Instance infrastructure for each object in order to allow Geometry Modifiers at render time, it should be fairly simple to add Displacement support.