Cleanup: some refactoring in mapped mesh extraction

* Flip the logic to first detect if we are dealing with an unmodified mesh
  in editmode. And then if not, detect if we need a mapping or not.
* runtime.is_original is only valid for the bmesh wrapper. Rename it to clarify
  that and only check it when the mesh is a bmesh wrapper.
* Remove MR_EXTRACT_MAPPED and instead check only for the existence of the
  origindex arrays. Previously it would sometimes access those arrays without
  MR_EXTRACT_MAPPED set, which according to a comment means they are invalid.

Differential Revision: https://developer.blender.org/D15676

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_mesh_types.h b/source/blender/makesdna/DNA_mesh_types.h
index 2eca84959b8..97355548b09 100644
--- a/source/blender/makesdna/DNA_mesh_types.h
+++ b/source/blender/makesdna/DNA_mesh_types.h
@@ -112,7 +112,7 @@ typedef struct Mesh_Runtime {
    * (most #eModifierTypeType_NonGeometrical modifiers). Otherwise the edit-mesh
    * data will be used for drawing, missing changes from modifiers. See T79517.
    */
-  char is_original;
+  char is_original_bmesh;
 
   /** #eMeshWrapperType and others. */
   char wrapper_type;