Sculpt: Fix #108267: Broken face set undo

BKE_sculpt_face_sets_ensure now takes an Object
as an argument and updates the internal PBVH's
face sets pointer.

source/blender/blenkernel/BKE_paint.h

@@ -877,7 +877,7 @@ void BKE_sculpt_update_object_after_eval(struct Depsgraph *depsgraph, struct Obj
  */
 struct MultiresModifierData *BKE_sculpt_multires_active(const struct Scene *scene,
                                                         struct Object *ob);
-int *BKE_sculpt_face_sets_ensure(struct Mesh *mesh);
+int *BKE_sculpt_face_sets_ensure(struct Object *ob);
 /**
  * Create the attribute used to store face visibility and retrieve its data.
  * Note that changes to the face visibility have to be propagated to other domains

source/blender/blenkernel/intern/paint.cc

@@ -1977,8 +1977,11 @@ void BKE_sculpt_update_object_for_edit(
   sculpt_update_object(depsgraph, ob_orig, ob_eval, need_pmap, is_paint_tool);
 }
 
-int *BKE_sculpt_face_sets_ensure(Mesh *mesh)
+int *BKE_sculpt_face_sets_ensure(Object *ob)
 {
+  SculptSession *ss = ob->sculpt;
+  Mesh *mesh = static_cast<Mesh *>(ob->data);
+
   using namespace blender;
   using namespace blender::bke;
   MutableAttributeAccessor attributes = mesh->attributes_for_write();
@@ -1990,8 +1993,14 @@ int *BKE_sculpt_face_sets_ensure(Mesh *mesh)
     face_sets.finish();
   }
 
-  return static_cast<int *>(CustomData_get_layer_named_for_write(
+  int *face_sets = static_cast<int *>(CustomData_get_layer_named_for_write(
       &mesh->pdata, CD_PROP_INT32, ".sculpt_face_set", mesh->totpoly));
+
+  if (ss->pbvh && ELEM(BKE_pbvh_type(ss->pbvh), PBVH_FACES, PBVH_GRIDS)) {
+    BKE_pbvh_face_sets_set(ss->pbvh, face_sets);
+  }
+
+  return face_sets;
 }
 
 bool *BKE_sculpt_hide_poly_ensure(Mesh *mesh)

source/blender/editors/sculpt_paint/paint_mask.cc

@@ -785,7 +785,7 @@ static void sculpt_gesture_init_face_set_properties(SculptGestureContext *sgcont
   sgcontext->operation = reinterpret_cast<SculptGestureOperation *>(
       MEM_cnew<SculptGestureFaceSetOperation>(__func__));
 
-  sgcontext->ss->face_sets = BKE_sculpt_face_sets_ensure(mesh);
+  sgcontext->ss->face_sets = BKE_sculpt_face_sets_ensure(sgcontext->vc.obact);
 
   SculptGestureFaceSetOperation *face_set_operation = (SculptGestureFaceSetOperation *)
                                                           sgcontext->operation;
@@ -1405,8 +1405,7 @@ static void sculpt_gesture_trim_begin(bContext *C, SculptGestureContext *sgconte
 {
   Object *object = sgcontext->vc.obact;
   SculptSession *ss = object->sculpt;
-  Mesh *mesh = (Mesh *)object->data;
-  ss->face_sets = BKE_sculpt_face_sets_ensure(mesh);
+  ss->face_sets = BKE_sculpt_face_sets_ensure(object);
 
   Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
   sculpt_gesture_trim_calculate_depth(sgcontext);

source/blender/editors/sculpt_paint/sculpt.cc

@@ -5882,8 +5882,7 @@ static int sculpt_brush_stroke_invoke(bContext *C, wmOperator *op, const wmEvent
     BKE_sculpt_mask_layers_ensure(CTX_data_depsgraph_pointer(C), CTX_data_main(C), ob, mmd);
   }
   if (SCULPT_tool_is_face_sets(brush->sculpt_tool)) {
-    Mesh *mesh = BKE_object_get_original_mesh(ob);
-    ss->face_sets = BKE_sculpt_face_sets_ensure(mesh);
+    ss->face_sets = BKE_sculpt_face_sets_ensure(ob);
   }
 
   stroke = paint_stroke_new(C,

source/blender/editors/sculpt_paint/sculpt_expand.cc

@@ -2197,7 +2197,7 @@ static int sculpt_expand_invoke(bContext *C, wmOperator *op, const wmEvent *even
 
   Mesh *mesh = static_cast<Mesh *>(ob->data);
   if (ss->expand_cache->target == SCULPT_EXPAND_TARGET_FACE_SETS) {
-    ss->face_sets = BKE_sculpt_face_sets_ensure(mesh);
+    ss->face_sets = BKE_sculpt_face_sets_ensure(ob);
   }
 
   /* Face Set operations are not supported in dyntopo. */

source/blender/editors/sculpt_paint/sculpt_face_set.cc

@@ -344,8 +344,8 @@ static int sculpt_face_set_create_exec(bContext *C, wmOperator *op)
     return OPERATOR_CANCELLED;
   }
 
+  ss->face_sets = BKE_sculpt_face_sets_ensure(ob);
   Mesh *mesh = static_cast<Mesh *>(ob->data);
-  ss->face_sets = BKE_sculpt_face_sets_ensure(mesh);
 
   BKE_sculpt_update_object_for_edit(depsgraph, ob, true, mode == SCULPT_FACE_SET_MASKED, false);
 
@@ -636,7 +636,7 @@ static int sculpt_face_set_init_exec(bContext *C, wmOperator *op)
   const float threshold = RNA_float_get(op->ptr, "threshold");
 
   Mesh *mesh = static_cast<Mesh *>(ob->data);
-  ss->face_sets = BKE_sculpt_face_sets_ensure(mesh);
+  ss->face_sets = BKE_sculpt_face_sets_ensure(ob);
   const bke::AttributeAccessor attributes = mesh->attributes();
 
   switch (mode) {
@@ -1387,7 +1387,7 @@ static bool sculpt_face_set_edit_init(bContext *C, wmOperator *op)
     return false;
   }
 
-  ss->face_sets = BKE_sculpt_face_sets_ensure(BKE_mesh_from_object(ob));
+  ss->face_sets = BKE_sculpt_face_sets_ensure(ob);
   BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false, false);
 
   return true;

source/blender/editors/sculpt_paint/sculpt_undo.cc

@@ -619,10 +619,9 @@ static bool sculpt_undo_restore_face_sets(bContext *C,
   ViewLayer *view_layer = CTX_data_view_layer(C);
   BKE_view_layer_synced_ensure(scene, view_layer);
   Object *ob = BKE_view_layer_active_object_get(view_layer);
-  Mesh *me = BKE_object_get_original_mesh(ob);
   SculptSession *ss = ob->sculpt;
 
-  ss->face_sets = BKE_sculpt_face_sets_ensure(me);
+  ss->face_sets = BKE_sculpt_face_sets_ensure(ob);
   BKE_pbvh_face_sets_set(ss->pbvh, ss->face_sets);
 
   bool modified = false;