Use the BMesh symmetrize operator instead of using the modifier code.
While we could support shape-keys with the existing code used by the
mirror modifier, we'd need to add code-paths for evaluated mesh & bmesh
conversion to handle shape-keys differently just for this one case,
since we want to avoid copying & processing shape-keys layers for
evaluated meshes in general.
Was flipping around the 0-1 range, now (optionally) flip around each tile.
Also added this option for BMesh bmo_mirror.
Reviewed By: campbellbarton
Maniphest Tasks: T75793
Differential Revision: https://developer.blender.org/D7460
- Use 'BKE_object_defgroup' prefix for object functions.
- Rename 'defvert_verify_index' to 'defvert_ensure_index'
since this adds the group if it isn't found.