Subdiv: CCG, implement stitching of given faces

Will speed up (or rather bring speed back to what it is supposed to be)
for brushes like smooth.

3 files changed, 46 insertions, 1 deletions

diff --git a/source/blender/blenkernel/BKE_subdiv_ccg.h b/source/blender/blenkernel/BKE_subdiv_ccg.h
index 99037a25a64..83d97974a28 100644
--- a/source/blender/blenkernel/BKE_subdiv_ccg.h
+++ b/source/blender/blenkernel/BKE_subdiv_ccg.h
@@ -37,6 +37,7 @@
 #include "BLI_sys_types.h"
 
 struct CCGElem;
+struct CCGFace;
 struct CCGKey;
 struct DMFlagMat;
 struct Mesh;
@@ -182,4 +183,9 @@ void BKE_subdiv_ccg_recalc_normals(SubdivCCG *subdiv_ccg);
 /* Average grid coordinates and normals along the grid boundatries. */
 void BKE_subdiv_ccg_average_grids(SubdivCCG *subdiv_ccg);
 
+/* Similar to above, but only updates given faces. */
+void BKE_subdiv_ccg_average_stitch_faces(SubdivCCG *subdiv_ccg,
+                                         struct CCGFace **effected_faces,
+                                         int num_effected_faces);
+
 #endif  /* __BKE_SUBDIV_CCG_H__ */
diff --git a/source/blender/blenkernel/intern/multires.c b/source/blender/blenkernel/intern/multires.c
index e8b1a5faa67..7453e963eae 100644
--- a/source/blender/blenkernel/intern/multires.c
+++ b/source/blender/blenkernel/intern/multires.c
@@ -1358,7 +1358,7 @@ void multires_stitch_grids(Object *ob)
 	int num_faces;
 	BKE_pbvh_get_grid_updates(pbvh, false, (void ***)&faces, &num_faces);
 	if (num_faces) {
-		/* TODO(sergey): Only aveerage actually affected faces. */
+		BKE_subdiv_ccg_average_stitch_faces(subdiv_ccg, faces, num_faces);
 		BKE_subdiv_ccg_average_grids(subdiv_ccg);
 		MEM_freeN(faces);
 	}
diff --git a/source/blender/blenkernel/intern/subdiv_ccg.c b/source/blender/blenkernel/intern/subdiv_ccg.c
index bd8ccda789b..6744579d5c6 100644
--- a/source/blender/blenkernel/intern/subdiv_ccg.c
+++ b/source/blender/blenkernel/intern/subdiv_ccg.c
@@ -657,3 +657,42 @@ void BKE_subdiv_ccg_average_grids(SubdivCCG *subdiv_ccg)
 	                        subdiv_ccg_average_inner_grids_task,
 	                        &parallel_range_settings);
 }
+
+typedef struct StitchFacesInnerGridsData {
+	SubdivCCG *subdiv_ccg;
+	CCGKey *key;
+	struct CCGFace **effected_ccg_faces;
+} StitchFacesInnerGridsData;
+
+static void subdiv_ccg_stitch_face_inner_grids_task(
+        void *__restrict userdata_v,
+        const int face_index,
+        const ParallelRangeTLS *__restrict UNUSED(tls_v))
+{
+	StitchFacesInnerGridsData *data = userdata_v;
+	SubdivCCG *subdiv_ccg = data->subdiv_ccg;
+	CCGKey *key = data->key;
+	struct CCGFace **effected_ccg_faces = data->effected_ccg_faces;
+	struct CCGFace *effected_ccg_face = effected_ccg_faces[face_index];
+	SubdivCCGFace *face = (SubdivCCGFace *)effected_ccg_face;
+	subdiv_ccg_average_inner_face_grids(subdiv_ccg, key, face);
+}
+
+void BKE_subdiv_ccg_average_stitch_faces(SubdivCCG *subdiv_ccg,
+                                         struct CCGFace **effected_faces,
+                                         int num_effected_faces)
+{
+	CCGKey key;
+	BKE_subdiv_ccg_key_top_level(&key, subdiv_ccg);
+	StitchFacesInnerGridsData data = {
+	        .subdiv_ccg = subdiv_ccg,
+	        .key = &key,
+	        .effected_ccg_faces = effected_faces,
+	};
+	ParallelRangeSettings parallel_range_settings;
+	BLI_parallel_range_settings_defaults(&parallel_range_settings);
+	BLI_task_parallel_range(0, num_effected_faces,
+	                        &data,
+	                        subdiv_ccg_stitch_face_inner_grids_task,
+	                        &parallel_range_settings);
+}