Campbell Barton
4ba06ad0a8
Supported multi-threading for bm_mesh_loops_calc_normals. This is done by operating on vertex-loops instead of face-loops. Single threaded operation still loops over faces since iterating over vertices adds some overhead in the case of custom-normals as the order used for accessing loops must be the same as iterating of a faces loops. From isolated timing tests of bm_mesh_loops_calc_normals on high poly models, this gives between 3.5x to 10x speedup, with larger gains for meshes with custom-normals. NOTE: this is part one of two patches for multi-threaded auto-smooth, tagging edges as sharp is still single threaded. Reviewed By: mont29 Ref D11928