Modifiers: every modifier now copies mesh settings, fixing texture space issues

Modifier stack evaluation would copy mesh settings other than mesh topology
automatically, outside of the individual modifier evaluation. This leads to hard
to understand code, and makes it unclear which settings are available in following
modifiers, and which only after the entire stack is evaluated.

Now every modifier is responsible to ensure the mesh it outputs preserves materials,
texture space and other settings, or alters them as needed.

Fixes T64739: incorrect texture space for various modifiers

Differential Revision: https://developer.blender.org/D5808

1 files changed, 10 insertions, 40 deletions

diff --git a/source/blender/blenkernel/intern/DerivedMesh.c b/source/blender/blenkernel/intern/DerivedMesh.c
index 010e162f49d..4849d631493 100644
--- a/source/blender/blenkernel/intern/DerivedMesh.c
+++ b/source/blender/blenkernel/intern/DerivedMesh.c
@@ -729,7 +729,7 @@ static Mesh *create_orco_mesh(Object *ob, Mesh *me, BMEditMesh *em, int layer)
   int free;
 
   if (em) {
-    mesh = BKE_mesh_from_bmesh_for_eval_nomain(em->bm, NULL);
+    mesh = BKE_mesh_from_bmesh_for_eval_nomain(em->bm, NULL, me);
   }
   else {
     mesh = BKE_mesh_copy_for_eval(me, true);
@@ -797,14 +797,6 @@ static void editmesh_update_statvis_color(const Scene *scene, Object *ob)
   BKE_editmesh_statvis_calc(em, me->runtime.edit_data, &scene->toolsettings->statvis);
 }
 
-static void mesh_copy_autosmooth(Mesh *me, Mesh *me_orig)
-{
-  if (me_orig->flag & ME_AUTOSMOOTH) {
-    me->flag |= ME_AUTOSMOOTH;
-    me->smoothresh = me_orig->smoothresh;
-  }
-}
-
 static void mesh_calc_modifier_final_normals(const Mesh *mesh_input,
                                              const CustomData_MeshMasks *final_datamask,
                                              const bool sculpt_dyntopo,
@@ -881,18 +873,8 @@ static void mesh_calc_finalize(const Mesh *mesh_input, Mesh *mesh_eval)
   /* Make sure the name is the same. This is because mesh allocation from template does not
    * take care of naming. */
   BLI_strncpy(mesh_eval->id.name, mesh_input->id.name, sizeof(mesh_eval->id.name));
-  /* Make sure materials are preserved from the input. */
-  if (mesh_eval->mat != NULL) {
-    MEM_freeN(mesh_eval->mat);
-  }
-  mesh_eval->mat = MEM_dupallocN(mesh_input->mat);
-  mesh_eval->totcol = mesh_input->totcol;
   /* Make evaluated mesh to share same edit mesh pointer as original and copied meshes. */
   mesh_eval->edit_mesh = mesh_input->edit_mesh;
-  /* Copy auth-smooth settings which are also not taken care about by mesh allocation from a
-   * template. */
-  mesh_eval->flag |= (mesh_input->flag & ME_AUTOSMOOTH);
-  mesh_eval->smoothresh = mesh_input->smoothresh;
 }
 
 static void mesh_calc_modifiers(struct Depsgraph *depsgraph,
@@ -1220,8 +1202,6 @@ static void mesh_calc_modifiers(struct Depsgraph *depsgraph,
           MEM_freeN(deformed_verts);
           deformed_verts = NULL;
         }
-
-        mesh_copy_autosmooth(mesh_final, mesh_input);
       }
 
       /* create an orco mesh in parallel */
@@ -1533,8 +1513,8 @@ static void editbmesh_calc_modifiers(struct Depsgraph *depsgraph,
   /* Evaluate modifiers up to certain index to get the mesh cage. */
   int cageIndex = modifiers_getCageIndex(scene, ob, NULL, 1);
   if (r_cage && cageIndex == -1) {
-    mesh_cage = BKE_mesh_from_editmesh_with_coords_thin_wrap(em_input, &final_datamask, NULL);
-    mesh_copy_autosmooth(mesh_cage, mesh_input);
+    mesh_cage = BKE_mesh_from_editmesh_with_coords_thin_wrap(
+        em_input, &final_datamask, NULL, mesh_input);
   }
 
   /* Clear errors before evaluation. */
@@ -1574,9 +1554,8 @@ static void editbmesh_calc_modifiers(struct Depsgraph *depsgraph,
       }
       else if (isPrevDeform && mti->dependsOnNormals && mti->dependsOnNormals(md)) {
         if (mesh_final == NULL) {
-          mesh_final = BKE_mesh_from_bmesh_for_eval_nomain(em_input->bm, NULL);
+          mesh_final = BKE_mesh_from_bmesh_for_eval_nomain(em_input->bm, NULL, mesh_input);
           ASSERT_IS_VALID_MESH(mesh_final);
-          mesh_copy_autosmooth(mesh_final, mesh_input);
         }
         BLI_assert(deformed_verts != NULL);
         BKE_mesh_vert_coords_apply(mesh_final, deformed_verts);
@@ -1607,11 +1586,9 @@ static void editbmesh_calc_modifiers(struct Depsgraph *depsgraph,
         }
       }
       else {
-        mesh_final = BKE_mesh_from_bmesh_for_eval_nomain(em_input->bm, NULL);
+        mesh_final = BKE_mesh_from_bmesh_for_eval_nomain(em_input->bm, NULL, mesh_input);
         ASSERT_IS_VALID_MESH(mesh_final);
 
-        mesh_copy_autosmooth(mesh_final, mesh_input);
-
         if (deformed_verts) {
           BKE_mesh_vert_coords_apply(mesh_final, deformed_verts);
         }
@@ -1674,8 +1651,6 @@ static void editbmesh_calc_modifiers(struct Depsgraph *depsgraph,
           MEM_freeN(deformed_verts);
           deformed_verts = NULL;
         }
-
-        mesh_copy_autosmooth(mesh_final, mesh_input);
       }
       mesh_final->runtime.deformed_only = false;
     }
@@ -1695,8 +1670,10 @@ static void editbmesh_calc_modifiers(struct Depsgraph *depsgraph,
           me_orig->runtime.edit_data->vertexCos = MEM_dupallocN(deformed_verts);
         }
         mesh_cage = BKE_mesh_from_editmesh_with_coords_thin_wrap(
-            em_input, &final_datamask, deformed_verts ? MEM_dupallocN(deformed_verts) : NULL);
-        mesh_copy_autosmooth(mesh_cage, mesh_input);
+            em_input,
+            &final_datamask,
+            deformed_verts ? MEM_dupallocN(deformed_verts) : NULL,
+            mesh_input);
       }
     }
 
@@ -1730,11 +1707,9 @@ static void editbmesh_calc_modifiers(struct Depsgraph *depsgraph,
   else {
     /* this is just a copy of the editmesh, no need to calc normals */
     mesh_final = BKE_mesh_from_editmesh_with_coords_thin_wrap(
-        em_input, &final_datamask, deformed_verts);
+        em_input, &final_datamask, deformed_verts, mesh_input);
     deformed_verts = NULL;
 
-    mesh_copy_autosmooth(mesh_final, mesh_input);
-
     /* In this case, we should never have weight-modifying modifiers in stack... */
     if (do_init_statvis) {
       editmesh_update_statvis_color(scene, ob);
@@ -1854,11 +1829,6 @@ static void mesh_build_data(struct Depsgraph *depsgraph,
                       &ob->runtime.mesh_eval);
 
   BKE_object_boundbox_calc_from_mesh(ob, ob->runtime.mesh_eval);
-  /* Only copy texspace from orig mesh if some modifier (hint: smoke sim, see T58492)
-   * did not re-enable that flag (which always get disabled for eval mesh as a start). */
-  if (!(ob->runtime.mesh_eval->texflag & ME_AUTOSPACE)) {
-    BKE_mesh_texspace_copy_from_object(ob->runtime.mesh_eval, ob);
-  }
 
   assign_object_mesh_eval(ob);