Cleanup: Simplify BKE_mesh_nomain_to_mesh

- Remove "take ownership" argument which was confusing and always true
  - The argument made ownership very confusing
  - Better to avoid boolean arguments that switch a function's purpose
- Remove "mask" argument which was basically wrong and not used properly
  - "EVERYTHING" was used because developers are wary of removing data
  - Instead use `CD_MASK_MESH` for its purpose of original mesh data
- Remove use of shallow copied temporary mesh, which is unnecessary now
- Split shape key processing into separate functions and use C++ types
- Copy fields explicitly rather than using memcpy for the whole struct
- Use higher level functions and avoid redundant code
  - The whole idea is pretty simple and can be built from standard logic
- Adjust `CustomData` logic to be consistent with "assign" expectations
  - Clear the layer data from the source, and moves the anonymous ID

Differential Revision: https://developer.blender.org/D15857

5 files changed, 8 insertions, 9 deletions

diff --git a/source/blender/editors/mesh/editmesh_mask_extract.c b/source/blender/editors/mesh/editmesh_mask_extract.c
index 6a080e78086..a4d41400bae 100644
--- a/source/blender/editors/mesh/editmesh_mask_extract.c
+++ b/source/blender/editors/mesh/editmesh_mask_extract.c
@@ -204,7 +204,7 @@ static int geometry_extract_apply(bContext *C,
     local_view_bits = v3d->local_view_uuid;
   }
   Object *new_ob = ED_object_add_type(C, OB_MESH, NULL, ob->loc, ob->rot, false, local_view_bits);
-  BKE_mesh_nomain_to_mesh(new_mesh, new_ob->data, new_ob, &CD_MASK_EVERYTHING, true);
+  BKE_mesh_nomain_to_mesh(new_mesh, new_ob->data, new_ob);
 
   /* Remove the Face Sets as they need to be recreated when entering Sculpt Mode in the new object.
    * TODO(pablodobarro): In the future we can try to preserve them from the original mesh. */
@@ -548,7 +548,7 @@ static int paint_mask_slice_exec(bContext *C, wmOperator *op)
     /* Remove the mask from the new object so it can be sculpted directly after slicing. */
     CustomData_free_layers(&new_ob_mesh->vdata, CD_PAINT_MASK, new_ob_mesh->totvert);
 
-    BKE_mesh_nomain_to_mesh(new_ob_mesh, new_ob->data, new_ob, &CD_MASK_MESH, true);
+    BKE_mesh_nomain_to_mesh(new_ob_mesh, new_ob->data, new_ob);
     BKE_mesh_copy_parameters_for_eval(new_ob->data, mesh);
     WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, new_ob);
     BKE_mesh_batch_cache_dirty_tag(new_ob->data, BKE_MESH_BATCH_DIRTY_ALL);
@@ -557,7 +557,7 @@ static int paint_mask_slice_exec(bContext *C, wmOperator *op)
     WM_event_add_notifier(C, NC_GEOM | ND_DATA, new_ob->data);
   }
 
-  BKE_mesh_nomain_to_mesh(new_mesh, ob->data, ob, &CD_MASK_MESH, true);
+  BKE_mesh_nomain_to_mesh(new_mesh, ob->data, ob);
 
   if (ob->mode == OB_MODE_SCULPT) {
     SculptSession *ss = ob->sculpt;
diff --git a/source/blender/editors/object/object_add.cc b/source/blender/editors/object/object_add.cc
index ddd54aa7953..c651affd96a 100644
--- a/source/blender/editors/object/object_add.cc
+++ b/source/blender/editors/object/object_add.cc
@@ -3151,7 +3151,7 @@ static int object_convert_exec(bContext *C, wmOperator *op)
       BKE_mesh_edges_set_draw_render(me_eval);
       BKE_object_material_from_eval_data(bmain, newob, &me_eval->id);
       Mesh *new_mesh = (Mesh *)newob->data;
-      BKE_mesh_nomain_to_mesh(me_eval, new_mesh, newob, &CD_MASK_MESH, true);
+      BKE_mesh_nomain_to_mesh(me_eval, new_mesh, newob);
 
       if (do_merge_customdata) {
         BKE_mesh_merge_customdata_for_apply_modifier(new_mesh);
diff --git a/source/blender/editors/object/object_modifier.cc b/source/blender/editors/object/object_modifier.cc
index 9bb82cc086c..2de33a3563a 100644
--- a/source/blender/editors/object/object_modifier.cc
+++ b/source/blender/editors/object/object_modifier.cc
@@ -763,7 +763,7 @@ static bool modifier_apply_obdata(
 
       Main *bmain = DEG_get_bmain(depsgraph);
       BKE_object_material_from_eval_data(bmain, ob, &mesh_applied->id);
-      BKE_mesh_nomain_to_mesh(mesh_applied, me, ob, &CD_MASK_MESH, true);
+      BKE_mesh_nomain_to_mesh(mesh_applied, me, ob);
 
       /* Anonymous attributes shouldn't be available on the applied geometry. */
       me->attributes_for_write().remove_anonymous();
diff --git a/source/blender/editors/object/object_remesh.cc b/source/blender/editors/object/object_remesh.cc
index 09489c50e9d..a6b51048209 100644
--- a/source/blender/editors/object/object_remesh.cc
+++ b/source/blender/editors/object/object_remesh.cc
@@ -179,7 +179,7 @@ static int voxel_remesh_exec(bContext *C, wmOperator *op)
     BKE_remesh_reproject_vertex_paint(new_mesh, mesh);
   }
 
-  BKE_mesh_nomain_to_mesh(new_mesh, mesh, ob, &CD_MASK_MESH, true);
+  BKE_mesh_nomain_to_mesh(new_mesh, mesh, ob);
 
   if (smooth_normals) {
     BKE_mesh_smooth_flag_set(static_cast<Mesh *>(ob->data), true);
@@ -905,7 +905,7 @@ static void quadriflow_start_job(void *customdata, short *stop, short *do_update
     BKE_mesh_remesh_reproject_paint_mask(new_mesh, mesh);
   }
 
-  BKE_mesh_nomain_to_mesh(new_mesh, mesh, ob, &CD_MASK_MESH, true);
+  BKE_mesh_nomain_to_mesh(new_mesh, mesh, ob);
 
   if (qj->smooth_normals) {
     BKE_mesh_smooth_flag_set(static_cast<Mesh *>(ob->data), true);
diff --git a/source/blender/editors/sculpt_paint/paint_mask.c b/source/blender/editors/sculpt_paint/paint_mask.c
index 332a0830081..0ea45f83336 100644
--- a/source/blender/editors/sculpt_paint/paint_mask.c
+++ b/source/blender/editors/sculpt_paint/paint_mask.c
@@ -1315,8 +1315,7 @@ static void sculpt_gesture_apply_trim(SculptGestureContext *sgcontext)
                                             }),
                                             sculpt_mesh);
   BM_mesh_free(bm);
-  BKE_mesh_nomain_to_mesh(
-      result, sgcontext->vc.obact->data, sgcontext->vc.obact, &CD_MASK_MESH, true);
+  BKE_mesh_nomain_to_mesh(result, sgcontext->vc.obact->data, sgcontext->vc.obact);
 }
 
 static void sculpt_gesture_trim_begin(bContext *C, SculptGestureContext *sgcontext)