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!

source/blender/blenkernel/BKE_paint.h

@@ -135,6 +135,8 @@ typedef struct SculptSession {
 
 	/* BMesh for dynamic topology sculpting */
 	struct BMesh *bm;
+	int cd_vert_node_offset;
+	int cd_face_node_offset;
 	bool bm_smooth_shading;
 	/* Undo/redo log for dynamic topology sculpting */
 	struct BMLog *bm_log;

source/blender/blenkernel/BKE_pbvh.h

@@ -67,7 +67,7 @@ void BKE_pbvh_build_grids(PBVH *bvh, struct CCGElem **grid_elems,
                           struct DMGridAdjacency *gridadj, int totgrid,
                           struct CCGKey *key, void **gridfaces, struct DMFlagMat *flagmats,
                           unsigned int **grid_hidden);
-void BKE_pbvh_build_bmesh(PBVH *bvh, struct BMesh *bm, bool smooth_shading, struct BMLog *log);
+void BKE_pbvh_build_bmesh(PBVH *bvh, struct BMesh *bm, bool smooth_shading, struct BMLog *log, const int cd_vert_node_offset, const int cd_face_node_offset);
 
 void BKE_pbvh_free(PBVH *bvh);
 void BKE_pbvh_free_layer_disp(PBVH *bvh);

source/blender/blenkernel/intern/cdderivedmesh.c

@@ -269,7 +269,8 @@ static PBVH *cdDM_getPBVH(Object *ob, DerivedMesh *dm)
 
 		BKE_pbvh_build_bmesh(cddm->pbvh, ob->sculpt->bm,
 		                     ob->sculpt->bm_smooth_shading,
-		                     ob->sculpt->bm_log);
+		                     ob->sculpt->bm_log, ob->sculpt->cd_vert_node_offset,
+		                     ob->sculpt->cd_face_node_offset);
 
 		pbvh_show_diffuse_color_set(cddm->pbvh, ob->sculpt->show_diffuse_color);
 	}

source/blender/blenkernel/intern/customdata.c

@@ -1037,17 +1037,6 @@ static void layerDefault_mvert_skin(void *data, int count)
 	}
 }
 
-static void layerDefault_dyntopo_node(void *data, int count)
-{
-	int *indices = data;
-	int i;
-
-	for (i = 0; i < count; i++) {
-		indices[i] = DYNTOPO_NODE_NONE;
-	}
-}
-
-
 static void layerInterp_mvert_skin(void **sources, const float *weights,
                                    const float *UNUSED(sub_weights),
                                    int count, void *dest)
@@ -1196,8 +1185,6 @@ static const LayerTypeInfo LAYERTYPEINFO[CD_NUMTYPES] = {
 	{sizeof(float[4]), "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
 	/* 40: CD_TESSLOOPNORMAL */
 	{sizeof(short[4][3]), "", 0, NULL, NULL, NULL, NULL, layerSwap_flnor, NULL},
-    /* 41: CD_DYNTOPO_NODE */
-	{sizeof(int), "", 0, NULL, NULL, NULL, NULL, NULL, layerDefault_dyntopo_node},
 };
 
 /* note, numbers are from trunk and need updating for bmesh */
@@ -1214,7 +1201,6 @@ static const char *LAYERTYPENAMES[CD_NUMTYPES] = {
 	/* 30-34 */ "CDSubSurfCrease", "CDOrigSpaceLoop", "CDPreviewLoopCol", "CDBMElemPyPtr", "CDPaintMask",
 	/* 35-36 */ "CDGridPaintMask", "CDMVertSkin",
 	/* 37-40 */ "CDFreestyleEdge", "CDFreestyleFace", "CDMLoopTangent", "CDTessLoopNormal",
-    /* 41 */ "CDDyntopoNode"
 };
 
 

source/blender/blenkernel/intern/pbvh_bmesh.c

@@ -96,8 +96,7 @@ static void pbvh_bmesh_node_finalize(PBVH *bvh, int node_index, const int cd_ver
 }
 
 /* Recursively split the node if it exceeds the leaf_limit */
-static void pbvh_bmesh_node_split(PBVH *bvh, GHash *prim_bbc, int node_index,
-                                  const int cd_vert_node_offset, const int cd_face_node_offset)
+static void pbvh_bmesh_node_split(PBVH *bvh, GHash *prim_bbc, int node_index)
 {
 	GSet *empty, *other;
 	GSetIterator gs_iter;
@@ -105,7 +104,8 @@ static void pbvh_bmesh_node_split(PBVH *bvh, GHash *prim_bbc, int node_index,
 	BB cb;
 	float mid;
 	int axis, children;
-
+	const int cd_vert_node_offset = bvh->cd_vert_node_offset;
+	const int cd_face_node_offset = bvh->cd_face_node_offset;
 	n = &bvh->nodes[node_index];
 
 	if (BLI_gset_size(n->bm_faces) <= bvh->leaf_limit) {
@@ -210,8 +210,8 @@ static void pbvh_bmesh_node_split(PBVH *bvh, GHash *prim_bbc, int node_index,
 	
 	/* Recurse */
 	c1 = c2 = NULL;
-	pbvh_bmesh_node_split(bvh, prim_bbc, children, cd_vert_node_offset, cd_face_node_offset);
-	pbvh_bmesh_node_split(bvh, prim_bbc, children + 1, cd_vert_node_offset, cd_face_node_offset);
+	pbvh_bmesh_node_split(bvh, prim_bbc, children);
+	pbvh_bmesh_node_split(bvh, prim_bbc, children + 1);
 
 	/* Array maybe reallocated, update current node pointer */
 	n = &bvh->nodes[node_index];
@@ -224,7 +224,7 @@ static void pbvh_bmesh_node_split(PBVH *bvh, GHash *prim_bbc, int node_index,
 }
 
 /* Recursively split the node if it exceeds the leaf_limit */
-static bool pbvh_bmesh_node_limit_ensure(PBVH *bvh, int node_index, const int cd_vert_node_offset, const int cd_face_node_offset)
+static bool pbvh_bmesh_node_limit_ensure(PBVH *bvh, int node_index)
 {
 	GHash *prim_bbc;
 	GSet *bm_faces;
@@ -260,7 +260,7 @@ static bool pbvh_bmesh_node_limit_ensure(PBVH *bvh, int node_index, const int cd
 		BLI_ghash_insert(prim_bbc, f, bbc);
 	}
 
-	pbvh_bmesh_node_split(bvh, prim_bbc, node_index, cd_vert_node_offset, cd_face_node_offset);
+	pbvh_bmesh_node_split(bvh, prim_bbc, node_index);
 
 	BLI_ghash_free(prim_bbc, NULL, NULL);
 	MEM_freeN(bbc_array);
@@ -1144,16 +1144,16 @@ void pbvh_bmesh_normals_update(PBVHNode **nodes, int totnode)
 /***************************** Public API *****************************/
 
 /* Build a PBVH from a BMesh */
-void BKE_pbvh_build_bmesh(PBVH *bvh, BMesh *bm, bool smooth_shading, BMLog *log)
+void BKE_pbvh_build_bmesh(PBVH *bvh, BMesh *bm, bool smooth_shading, BMLog *log,
+                          const int cd_vert_node_offset, const int cd_face_node_offset)
 {
 	BMIter iter;
 	BMFace *f;
 	PBVHNode *n;
 	int node_index = 0;
 
-	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);
-
+	bvh->cd_vert_node_offset = cd_vert_node_offset;
+	bvh->cd_face_node_offset = cd_face_node_offset;
 	bvh->bm = bm;
 
 	BKE_pbvh_bmesh_detail_size_set(bvh, 0.75);
@@ -1178,7 +1178,7 @@ void BKE_pbvh_build_bmesh(PBVH *bvh, BMesh *bm, bool smooth_shading, BMLog *log)
 
 	/* Recursively split the node until it is under the limit; if no
 	 * splitting occurs then finalize the existing leaf node */
-	if (!pbvh_bmesh_node_limit_ensure(bvh, node_index, cd_vert_node_offset, cd_face_node_offset))
+	if (!pbvh_bmesh_node_limit_ensure(bvh, node_index))
 		pbvh_bmesh_node_finalize(bvh, 0, cd_vert_node_offset, cd_face_node_offset);
 }
 
@@ -1190,8 +1190,8 @@ bool BKE_pbvh_bmesh_update_topology(PBVH *bvh, PBVHTopologyUpdateMode mode,
 	BLI_buffer_declare_static(BMFace *, edge_loops, BLI_BUFFER_NOP, 2);
 	BLI_buffer_declare_static(BMFace *, deleted_faces, BLI_BUFFER_NOP, 32);
 	const int cd_vert_mask_offset = CustomData_get_offset(&bvh->bm->vdata, CD_PAINT_MASK);
-	const int cd_vert_node_offset = CustomData_get_offset(&bvh->bm->vdata, CD_DYNTOPO_NODE);
-	const int cd_face_node_offset = CustomData_get_offset(&bvh->bm->pdata, CD_DYNTOPO_NODE);
+	const int cd_vert_node_offset = bvh->cd_vert_node_offset;
+	const int cd_face_node_offset = bvh->cd_face_node_offset;
 
 	bool modified = false;
 	int n;
@@ -1312,9 +1312,6 @@ void BKE_pbvh_bmesh_after_stroke(PBVH *bvh)
 {
 	int i;
 
-	const int cd_vert_node_offset = CustomData_get_offset(&bvh->bm->vdata, CD_DYNTOPO_NODE);
-	const int cd_face_node_offset = CustomData_get_offset(&bvh->bm->pdata, CD_DYNTOPO_NODE);
-
 	for (i = 0; i < bvh->totnode; i++) {
 		PBVHNode *n = &bvh->nodes[i];
 		if (n->flag & PBVH_Leaf) {
@@ -1323,7 +1320,7 @@ void BKE_pbvh_bmesh_after_stroke(PBVH *bvh)
 
 			/* Recursively split nodes that have gotten too many
 			 * elements */
-			pbvh_bmesh_node_limit_ensure(bvh, i, cd_vert_node_offset, cd_face_node_offset);
+			pbvh_bmesh_node_limit_ensure(bvh, i);
 		}
 	}
 }

source/blender/blenkernel/intern/pbvh_intern.h

@@ -162,6 +162,8 @@ struct PBVH {
 	BMesh *bm;
 	float bm_max_edge_len;
 	float bm_min_edge_len;
+	int cd_vert_node_offset;
+	int cd_face_node_offset;
 
 	struct BMLog *bm_log;
 };

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);
 

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,

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 {

source/blender/makesdna/DNA_customdata_types.h

@@ -63,10 +63,9 @@ typedef struct CustomDataExternal {
  * layers, each with a data type (e.g. MTFace, MDeformVert, etc.). */
 typedef struct CustomData {
 	CustomDataLayer *layers;      /* CustomDataLayers, ordered by type */
-	int typemap[42];              /* runtime only! - maps types to indices of first layer of that type,
+	int typemap[41];              /* runtime only! - maps types to indices of first layer of that type,
 	                               * MUST be >= CD_NUMTYPES, but we cant use a define here.
 	                               * Correct size is ensured in CustomData_update_typemap assert() */
-	int pad;
 	int totlayer, maxlayer;       /* number of layers, size of layers array */
 	int totsize;                  /* in editmode, total size of all data layers */
 	struct BLI_mempool *pool;     /* (BMesh Only): Memory pool for allocation of blocks */
@@ -121,8 +120,7 @@ enum {
 	CD_MLOOPTANGENT     = 39,
 	CD_TESSLOOPNORMAL   = 40,
 
-	CD_DYNTOPO_NODE     = 41,
-	CD_NUMTYPES         = 42
+	CD_NUMTYPES         = 41
 };
 
 /* Bits for CustomDataMask */
@@ -170,8 +168,6 @@ enum {
 #define CD_MASK_MLOOPTANGENT    (1LL << CD_MLOOPTANGENT)
 #define CD_MASK_TESSLOOPNORMAL  (1LL << CD_TESSLOOPNORMAL)
 
-#define CD_MASK_DYNTOPO_NODE    (1LL << CD_DYNTOPO_NODE)
-
 /* CustomData.flag */
 enum {
 	/* Indicates layer should not be copied by CustomData_from_template or CustomData_copy_data */