Refactor to Dyntopo node customdata commit.

Don't use a dedicated node layer but use temporary int layer instead.
Works like a charm as long as we are careful resetting the layer when
needed (after pbvh clearing and always after bmesh has been filled in
undo)

Tip by Campbell, thanks!

3 files changed, 47 insertions, 13 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 4873587e9f5..dbf99e96053 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -4793,15 +4793,14 @@ void sculpt_pbvh_clear(Object *ob)
 	BKE_object_free_derived_caches(ob);
 }
 
-void sculpt_dyntopo_node_layers_reset(BMesh *bm)
+void sculpt_dyntopo_node_layers_reset(SculptSession *ss)
 {
-	/* A bit lame, but for now just recreate the PBVH. The alternative
-	 * is to store changes to the PBVH in the undo stack. */
 	BMFace *f;
 	BMVert *v;
 	BMIter iter;
-	const int cd_vert_node_offset = CustomData_get_offset(&bm->vdata, CD_DYNTOPO_NODE);
-	const int cd_face_node_offset = CustomData_get_offset(&bm->pdata, CD_DYNTOPO_NODE);
+	BMesh *bm = ss->bm;
+	int cd_vert_node_offset = ss->cd_vert_node_offset;
+	int cd_face_node_offset = ss->cd_face_node_offset;
 
 	/* clear the elements of the node information */
 	BM_ITER_MESH(v, &iter, bm, BM_VERTS_OF_MESH) {
@@ -4813,6 +4812,34 @@ void sculpt_dyntopo_node_layers_reset(BMesh *bm)
 	}
 }
 
+void sculpt_dyntopo_node_layers_add(SculptSession *ss)
+{
+	int cd_node_layer_index;
+
+	char layer_id[] = "_dyntopo_node_id";
+
+	cd_node_layer_index = CustomData_get_named_layer_index(&ss->bm->vdata, CD_PROP_INT, layer_id);
+	if (cd_node_layer_index == -1) {
+		BM_data_layer_add_named(ss->bm, &ss->bm->vdata, CD_PROP_INT, layer_id);
+		cd_node_layer_index = CustomData_get_named_layer_index(&ss->bm->vdata, CD_PROP_INT, layer_id);
+	}
+
+	ss->cd_vert_node_offset = CustomData_get_n_offset(&ss->bm->vdata, CD_PROP_INT, cd_node_layer_index);
+
+	ss->bm->vdata.layers[cd_node_layer_index].flag |= CD_FLAG_TEMPORARY;
+
+	cd_node_layer_index = CustomData_get_named_layer_index(&ss->bm->pdata, CD_PROP_INT, layer_id);
+	if (cd_node_layer_index == -1) {
+		BM_data_layer_add_named(ss->bm, &ss->bm->pdata, CD_PROP_INT, layer_id);
+		cd_node_layer_index = CustomData_get_named_layer_index(&ss->bm->pdata, CD_PROP_INT, layer_id);
+	}
+
+	ss->cd_face_node_offset = CustomData_get_n_offset(&ss->bm->pdata, CD_PROP_INT, cd_node_layer_index);
+
+	ss->bm->pdata.layers[cd_node_layer_index].flag |= CD_FLAG_TEMPORARY;
+}
+
+
 void sculpt_update_after_dynamic_topology_toggle(bContext *C)
 {
 	Scene *scene = CTX_data_scene(C);
@@ -4845,8 +4872,9 @@ void sculpt_dynamic_topology_enable(bContext *C)
 	BM_mesh_bm_from_me(ss->bm, me, true, true, ob->shapenr);
 	sculpt_dynamic_topology_triangulate(ss->bm);
 	BM_data_layer_add(ss->bm, &ss->bm->vdata, CD_PAINT_MASK);
-	BM_data_layer_add(ss->bm, &ss->bm->vdata, CD_DYNTOPO_NODE);
-	BM_data_layer_add(ss->bm, &ss->bm->pdata, CD_DYNTOPO_NODE);
+	sculpt_dyntopo_node_layers_add(ss);
+	/* make sure the data for existing faces are initialized */
+	sculpt_dyntopo_node_layers_reset(ss);
 	BM_mesh_normals_update(ss->bm);
 
 	/* Enable dynamic topology */
@@ -5303,7 +5331,7 @@ static int sculpt_detail_flood_fill_exec(bContext *C, wmOperator *UNUSED(op))
 
 	/* force rebuild of pbvh for better BB placement */
 	sculpt_pbvh_clear(ob);
-	sculpt_dyntopo_node_layers_reset(ss->bm);
+	sculpt_dyntopo_node_layers_reset(ss);
 	/* Redraw */
 	WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, ob);
 
diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index 79fd388e332..8cf5bf88bcc 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -42,13 +42,13 @@
 
 struct bContext;
 struct Brush;
-struct BMesh;
 struct KeyBlock;
 struct Mesh;
 struct MultiresModifierData;
 struct Object;
 struct Scene;
 struct Sculpt;
+struct SculptSession;
 struct SculptStroke;
 struct SculptUndoNode;
 
@@ -68,7 +68,8 @@ bool sculpt_stroke_get_location(bContext *C, float out[3], const float mouse[2])
 
 /* Dynamic topology */
 void sculpt_pbvh_clear(Object *ob);
-void sculpt_dyntopo_node_layers_reset(struct BMesh *bm);
+void sculpt_dyntopo_node_layers_reset(struct SculptSession *ss);
+void sculpt_dyntopo_node_layers_add(struct SculptSession *ss);
 void sculpt_update_after_dynamic_topology_toggle(bContext *C);
 void sculpt_dynamic_topology_enable(struct bContext *C);
 void sculpt_dynamic_topology_disable(struct bContext *C,
diff --git a/source/blender/editors/sculpt_paint/sculpt_undo.c b/source/blender/editors/sculpt_paint/sculpt_undo.c
index b0fd7faa70d..39df15bd985 100644
--- a/source/blender/editors/sculpt_paint/sculpt_undo.c
+++ b/source/blender/editors/sculpt_paint/sculpt_undo.c
@@ -301,7 +301,7 @@ static void sculpt_undo_bmesh_restore_generic(bContext *C,
 			MEM_freeN(nodes);
 	}
 	else {
-		sculpt_dyntopo_node_layers_reset(ss->bm);
+		sculpt_dyntopo_node_layers_reset(ss);
 		sculpt_pbvh_clear(ob);
 	}
 }
@@ -318,8 +318,7 @@ static void sculpt_undo_bmesh_enable(Object *ob,
 	/* Create empty BMesh and enable logging */
 	ss->bm = BM_mesh_create(&bm_mesh_allocsize_default);
 	BM_data_layer_add(ss->bm, &ss->bm->vdata, CD_PAINT_MASK);
-	BM_data_layer_add(ss->bm, &ss->bm->vdata, CD_DYNTOPO_NODE);
-	BM_data_layer_add(ss->bm, &ss->bm->pdata, CD_DYNTOPO_NODE);
+	sculpt_dyntopo_node_layers_add(ss);
 	me->flag |= ME_SCULPT_DYNAMIC_TOPOLOGY;
 
 	/* Restore the BMLog using saved entries */
@@ -342,6 +341,9 @@ static void sculpt_undo_bmesh_restore_begin(bContext *C,
 		/* Restore the mesh from the first log entry */
 		BM_log_redo(ss->bm, ss->bm_log);
 
+		/* reset layers for all bmesh data */
+		sculpt_dyntopo_node_layers_reset(ss);
+
 		unode->applied = true;
 	}
 }
@@ -357,6 +359,9 @@ static void sculpt_undo_bmesh_restore_end(bContext *C,
 		/* Restore the mesh from the last log entry */
 		BM_log_undo(ss->bm, ss->bm_log);
 
+		/* reset layers for all bmesh data */
+		sculpt_dyntopo_node_layers_reset(ss);
+
 		unode->applied = false;
 	}
 	else {