Hans Goudey
8b93265c19
Because mesh vertex and face normals are just derived data, they can be calculated lazily instead of eagerly. Often normal calculation is a relatively expensive task, and the calculation is often redundant if the mesh is deformed afterwards anyway. Instead, normals should be calculated only when they are needed. This commit moves in that direction by adding a new function to tag a mesh's normals dirty and replacing normal calculation with it in some places. Differential Revision: https://developer.blender.org/D12107