Cleanup: split BKE_mesh_copy_settings into two functions

- BKE_mesh_copy_parameters_for_eval to be used for evaluated meshes only
  as it doesn't handle ID user-counts.

- BKE_mesh_copy_parameters is a general function for copying parameters
  between meshes.

source/blender/blenkernel/BKE_mesh.h

@@ -98,7 +98,8 @@ void BKE_mesh_looptri_get_real_edges(const struct Mesh *mesh,
 void BKE_mesh_free(struct Mesh *me);
 void BKE_mesh_clear_geometry(struct Mesh *me);
 struct Mesh *BKE_mesh_add(struct Main *bmain, const char *name);
-void BKE_mesh_copy_settings(struct Mesh *me_dst, const struct Mesh *me_src);
+void BKE_mesh_copy_parameters_for_eval(struct Mesh *me_dst, const struct Mesh *me_src);
+void BKE_mesh_copy_parameters(struct Mesh *me_dst, const struct Mesh *me_src);
 void BKE_mesh_update_customdata_pointers(struct Mesh *me, const bool do_ensure_tess_cd);
 void BKE_mesh_ensure_skin_customdata(struct Mesh *me);
 

source/blender/blenkernel/intern/DerivedMesh.cc

@@ -962,7 +962,7 @@ static Mesh *modifier_modify_mesh_and_geometry_set(ModifierData *md,
     /* Return an empty mesh instead of null.  */
     if (mesh_output == nullptr) {
       mesh_output = BKE_mesh_new_nomain(0, 0, 0, 0, 0);
-      BKE_mesh_copy_settings(mesh_output, input_mesh);
+      BKE_mesh_copy_parameters_for_eval(mesh_output, input_mesh);
     }
   }
 

source/blender/blenkernel/intern/fluid.c

@@ -4234,7 +4234,7 @@ struct Mesh *BKE_fluid_modifier_do(
     result = BKE_mesh_copy_for_eval(me, false);
   }
   else {
-    BKE_mesh_copy_settings(result, me);
+    BKE_mesh_copy_parameters_for_eval(result, me);
   }
 
   /* Liquid simulation has a texture space that based on the bounds of the fluid mesh.

source/blender/blenkernel/intern/geometry_set_instances.cc

@@ -399,7 +399,7 @@ static Mesh *join_mesh_topology_and_builtin_attributes(Span<GeometryInstanceGrou
     const GeometrySet &set = set_group.geometry_set;
     if (set.has_mesh()) {
       const Mesh &mesh = *set.get_mesh_for_read();
-      BKE_mesh_copy_settings(new_mesh, &mesh);
+      BKE_mesh_copy_parameters_for_eval(new_mesh, &mesh);
       break;
     }
   }

source/blender/blenkernel/intern/mesh.c

@@ -900,9 +900,11 @@ Mesh *BKE_mesh_new_nomain(
   return mesh;
 }
 
-/* Copy user editable settings that we want to preserve through the modifier stack
- * or operations where a mesh with new topology is created based on another mesh. */
-void BKE_mesh_copy_settings(Mesh *me_dst, const Mesh *me_src)
+/**
+ * Copy user editable settings that we want to preserve
+ * when a new mesh is based on an existing mesh.
+ */
+void BKE_mesh_copy_parameters(Mesh *me_dst, const Mesh *me_src)
 {
   /* Copy general settings. */
   me_dst->editflag = me_src->editflag;
@@ -920,6 +922,20 @@ void BKE_mesh_copy_settings(Mesh *me_dst, const Mesh *me_src)
   me_dst->texflag = me_src->texflag;
   copy_v3_v3(me_dst->loc, me_src->loc);
   copy_v3_v3(me_dst->size, me_src->size);
+}
+
+/**
+ * A version of #BKE_mesh_copy_parameters that is intended for evaluated output
+ * (the modifier stack for example).
+ *
+ * \warning User counts are not handled for ID's.
+ */
+void BKE_mesh_copy_parameters_for_eval(Mesh *me_dst, const Mesh *me_src)
+{
+  /* User counts aren't handled, don't copy into a mesh from #G_MAIN. */
+  BLI_assert(me_dst->id.tag & (LIB_TAG_NO_MAIN | LIB_TAG_COPIED_ON_WRITE));
+
+  BKE_mesh_copy_parameters(me_dst, me_src);
 
   /* Copy materials. */
   if (me_dst->mat != NULL) {
@@ -951,7 +967,7 @@ Mesh *BKE_mesh_new_nomain_from_template_ex(const Mesh *me_src,
   me_dst->totpoly = polys_len;
 
   me_dst->cd_flag = me_src->cd_flag;
-  BKE_mesh_copy_settings(me_dst, me_src);
+  BKE_mesh_copy_parameters_for_eval(me_dst, me_src);
 
   CustomData_copy(&me_src->vdata, &me_dst->vdata, mask.vmask, CD_CALLOC, verts_len);
   CustomData_copy(&me_src->edata, &me_dst->edata, mask.emask, CD_CALLOC, edges_len);
@@ -1038,7 +1054,7 @@ Mesh *BKE_mesh_from_bmesh_nomain(BMesh *bm,
   BLI_assert(params->calc_object_remap == false);
   Mesh *mesh = BKE_id_new_nomain(ID_ME, NULL);
   BM_mesh_bm_to_me(NULL, bm, mesh, params);
-  BKE_mesh_copy_settings(mesh, me_settings);
+  BKE_mesh_copy_parameters_for_eval(mesh, me_settings);
   return mesh;
 }
 
@@ -1048,7 +1064,7 @@ Mesh *BKE_mesh_from_bmesh_for_eval_nomain(BMesh *bm,
 {
   Mesh *mesh = BKE_id_new_nomain(ID_ME, NULL);
   BM_mesh_bm_to_me_for_eval(bm, mesh, cd_mask_extra);
-  BKE_mesh_copy_settings(mesh, me_settings);
+  BKE_mesh_copy_parameters_for_eval(mesh, me_settings);
   return mesh;
 }
 

source/blender/blenkernel/intern/mesh_wrapper.c

@@ -58,7 +58,7 @@ Mesh *BKE_mesh_wrapper_from_editmesh_with_coords(BMEditMesh *em,
                                                  const Mesh *me_settings)
 {
   Mesh *me = BKE_id_new_nomain(ID_ME, NULL);
-  BKE_mesh_copy_settings(me, me_settings);
+  BKE_mesh_copy_parameters_for_eval(me, me_settings);
   BKE_mesh_runtime_ensure_edit_data(me);
 
   me->runtime.wrapper_type = ME_WRAPPER_TYPE_BMESH;

source/blender/editors/mesh/editmesh_mask_extract.c

@@ -229,7 +229,7 @@ static int geometry_extract_apply(bContext *C,
   /* Remove the mask from the new object so it can be sculpted directly after extracting. */
   CustomData_free_layers(&new_ob_mesh->vdata, CD_PAINT_MASK, new_ob_mesh->totvert);
 
-  BKE_mesh_copy_settings(new_ob_mesh, mesh);
+  BKE_mesh_copy_parameters_for_eval(new_ob_mesh, mesh);
 
   if (params->apply_shrinkwrap) {
     BKE_shrinkwrap_mesh_nearest_surface_deform(C, new_ob, ob);
@@ -567,7 +567,7 @@ static int paint_mask_slice_exec(bContext *C, wmOperator *op)
 
     BKE_mesh_nomain_to_mesh(new_ob_mesh, new_ob->data, new_ob, &CD_MASK_MESH, true);
     BKE_mesh_calc_normals(new_ob->data);
-    BKE_mesh_copy_settings(new_ob->data, mesh);
+    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);
     DEG_relations_tag_update(bmain);

source/blender/modifiers/intern/MOD_ocean.c

@@ -284,7 +284,7 @@ static Mesh *generate_ocean_geometry(OceanModifierData *omd, Mesh *mesh_orig, co
   gogd.sy /= gogd.ry;
 
   result = BKE_mesh_new_nomain(num_verts, 0, 0, num_polys * 4, num_polys);
-  BKE_mesh_copy_settings(result, mesh_orig);
+  BKE_mesh_copy_parameters_for_eval(result, mesh_orig);
 
   gogd.mverts = result->mvert;
   gogd.mpolys = result->mpoly;

source/blender/modifiers/intern/MOD_remesh.c

@@ -218,7 +218,7 @@ static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *UNUSED(ctx)
     }
   }
 
-  BKE_mesh_copy_settings(result, mesh);
+  BKE_mesh_copy_parameters_for_eval(result, mesh);
   BKE_mesh_calc_edges(result, true, false);
   result->runtime.cd_dirty_vert |= CD_MASK_NORMAL;
   return result;

source/blender/modifiers/intern/MOD_volume_to_mesh.cc

@@ -132,7 +132,7 @@ static void panelRegister(ARegionType *region_type)
 static Mesh *create_empty_mesh(const Mesh *input_mesh)
 {
   Mesh *new_mesh = BKE_mesh_new_nomain(0, 0, 0, 0, 0);
-  BKE_mesh_copy_settings(new_mesh, input_mesh);
+  BKE_mesh_copy_parameters_for_eval(new_mesh, input_mesh);
   return new_mesh;
 }
 
@@ -193,7 +193,7 @@ static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *
     return create_empty_mesh(input_mesh);
   }
 
-  BKE_mesh_copy_settings(mesh, input_mesh);
+  BKE_mesh_copy_parameters_for_eval(mesh, input_mesh);
   if (vmmd->flag & VOLUME_TO_MESH_USE_SMOOTH_SHADE) {
     BKE_mesh_smooth_flag_set(mesh, true);
   }

source/blender/nodes/geometry/nodes/node_geo_join_geometry.cc

@@ -83,7 +83,7 @@ static Mesh *join_mesh_topology_and_builtin_attributes(Span<const MeshComponent
 
   const Mesh *first_input_mesh = src_components[0]->get_for_read();
   Mesh *new_mesh = BKE_mesh_new_nomain(totverts, totedges, 0, totloops, totpolys);
-  BKE_mesh_copy_settings(new_mesh, first_input_mesh);
+  BKE_mesh_copy_parameters_for_eval(new_mesh, first_input_mesh);
 
   for (const int i : IndexRange(materials.size())) {
     Material *material = materials[i];