f9b2edbf01
Prevent crash from a mesh created around the time of Blender 4.0 with bad (negative) material indices on some faces. The Poly Haven folks were poked to fix the actual asset as well but it's simple enough for us to clamp in this code path, especially since we were already doing it for the upper bound. Pull Request: https://projects.blender.org/blender/blender/pulls/124026