Mesh: Avoid unnecessary normal calculation and dirty tags

This is mostly a cleanup to avoid hardcoding the eager calculation of
normals it isn't necessary, by reducing calls to `BKE_mesh_calc_normals`
and by removing calls to `BKE_mesh_normals_tag_dirty` when the mesh
is newly created and already has dirty normals anyway. This reduces
boilerplate code and makes the "dirty by default" state more clear.
Any regressions from this commit should be easy to fix, though the
lazy calculation is solid enough that none are expected.

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/blenkernel/intern/subdiv_mesh.c b/source/blender/blenkernel/intern/subdiv_mesh.c
index 83e4336e3b1..83427adcb43 100644
--- a/source/blender/blenkernel/intern/subdiv_mesh.c
+++ b/source/blender/blenkernel/intern/subdiv_mesh.c
@@ -1155,7 +1155,7 @@ Mesh *BKE_subdiv_to_mesh(Subdiv *subdiv,
    * calculation. Since vertex normals are supposed to be a consistent cache, don't bother
    * calculating them here. The work may have been pointless anyway if the mesh is deformed or
    * changed afterwards. */
-  BKE_mesh_normals_tag_dirty(result);
+  BLI_assert(BKE_mesh_vertex_normals_are_dirty(result) || BKE_mesh_poly_normals_are_dirty(result));
   /* Free used memory. */
   subdiv_mesh_context_free(&subdiv_context);
   return result;