quote:Original post by Anonymous Poster
Any time you encounter a vertex which lies on a color, smoothing, texture or shader boundary, split it into as many copies of that vertex as there are unique combinations of these boundary parameters.

I said unique combinations, but I really should have said distinct combinations. For example, if you have a set of 4 polygons (P1, P2, P3, P4) which share a vertex V with associated UV coordinates (1.0, 1.0, 1.0, 0.5) and smoothing groups (1, 1, 2, 3), this gives you a total of three distinct combinations (out of four) in the form (UV, smoothing): (1.0, 1) (1.0, 2) and (0.5, 3).