BKE_mesh_validate is called by mesh.validate() Python API, as well as optionally
when doing file imports. This PR speeds it up a bit:
- Faster face data sorting by using parallel sort instead of qsort,
- One allocation for all face vertex indices, instead of a separate allocation
for each face,
- (more like a fix) Validation no longer adds a MDeformVert layer when there was
none in the input mesh.
- Small cleanups (more const inputs, etc.)
On my Windows/VS2022/Ryzen5950X machine, import time in seconds (validation on
before this PR -> validation on with this PR, validation off):
- USD (Intel Moore Lane): 9.1 -> 6.7, 4.8.
- OBJ (Blender 3.0 splash): 22.7 -> 18.6, 16.5.
Pull Request: https://projects.blender.org/blender/blender/pulls/121413
6efa5c16ab