Sculpt: Opaque vertex type for sculpt

This is a port of sculpt-dev's `SculptVertRef` refactor
(note that `SculptVertRef was renamed to PBVHVertRef`)
to master. `PBVHVertRef` is a structure that abstracts
the concept of a vertex in the sculpt code; it's simply
an `intptr_t` wrapped in a struct.

For `PBVH_FACES` and `PBVH_GRIDS` this struct stores a
vertex index, but for `BMesh` it stores a direct pointer
to a BMVert.  The intptr_t is wrapped in a struct to prevent
the accidental usage of it as an index.

There are many reasons to do this:

* Right now `BMesh` verts are not logical sculpt verts;
  to use the sculpt API they must first be converted to indices.
  This requires a lot of indirect lookups into tables, leading to performance
  loss.  It has also led to greater code complexity and duplication.
* Having an abstract vertex type makes it feasible to have one unified
  temporary attribute API for all three PBVH modes, which in turn
  made it rather trivial to port sculpt brushes to DynTopo in
  sculpt-dev (e.g. the layer brush, draw sharp, the smooth brushes,
  the paint brushes, etc).  This attribute API will be in a future patch.
* We need to do this anyway for the eventual move to C++.

Differential Revision: https://developer.blender.org/D14272
Reviewed By: Brecht Van Lommel
Ref D14272

1 files changed, 26 insertions, 10 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt_automasking.cc b/source/blender/editors/sculpt_paint/sculpt_automasking.cc
index bb101717c9b..a9fe8cc4b2f 100644
--- a/source/blender/editors/sculpt_paint/sculpt_automasking.cc
+++ b/source/blender/editors/sculpt_paint/sculpt_automasking.cc
@@ -114,16 +114,21 @@ static bool SCULPT_automasking_needs_factors_cache(const Sculpt *sd, const Brush
   return false;
 }
 
-float SCULPT_automasking_factor_get(AutomaskingCache *automasking, SculptSession *ss, int vert)
+float SCULPT_automasking_factor_get(AutomaskingCache *automasking,
+                                    SculptSession *ss,
+                                    PBVHVertRef vert)
 {
   if (!automasking) {
     return 1.0f;
   }
+
+  int index = BKE_pbvh_vertex_to_index(ss->pbvh, vert);
+
   /* If the cache is initialized with valid info, use the cache. This is used when the
    * automasking information can't be computed in real time per vertex and needs to be
    * initialized for the whole mesh when the stroke starts. */
   if (automasking->factor) {
-    return automasking->factor[vert];
+    return automasking->factor[index];
   }
 
   if (automasking->settings.flags & BRUSH_AUTOMASKING_FACE_SETS) {
@@ -178,13 +183,18 @@ struct AutomaskFloodFillData {
   char symm;
 };
 
-static bool automask_floodfill_cb(
-    SculptSession *ss, int from_v, int to_v, bool UNUSED(is_duplicate), void *userdata)
+static bool automask_floodfill_cb(SculptSession *ss,
+                                  PBVHVertRef from_v,
+                                  PBVHVertRef to_v,
+                                  bool UNUSED(is_duplicate),
+                                  void *userdata)
 {
   AutomaskFloodFillData *data = (AutomaskFloodFillData *)userdata;
+  int from_v_i = BKE_pbvh_vertex_to_index(ss->pbvh, from_v);
+  int to_v_i = BKE_pbvh_vertex_to_index(ss->pbvh, to_v);
 
-  data->automask_factor[to_v] = 1.0f;
-  data->automask_factor[from_v] = 1.0f;
+  data->automask_factor[to_v_i] = 1.0f;
+  data->automask_factor[from_v_i] = 1.0f;
   return (!data->use_radius ||
           SCULPT_is_vertex_inside_brush_radius_symm(
               SCULPT_vertex_co_get(ss, to_v), data->location, data->radius, data->symm));
@@ -243,7 +253,9 @@ static float *sculpt_face_sets_automasking_init(Sculpt *sd, Object *ob, float *a
   int tot_vert = SCULPT_vertex_count_get(ss);
   int active_face_set = SCULPT_active_face_set_get(ss);
   for (int i : IndexRange(tot_vert)) {
-    if (!SCULPT_vertex_has_face_set(ss, i, active_face_set)) {
+    PBVHVertRef vertex = BKE_pbvh_index_to_vertex(ss->pbvh, i);
+
+    if (!SCULPT_vertex_has_face_set(ss, vertex, active_face_set)) {
       automask_factor[i] *= 0.0f;
     }
   }
@@ -269,15 +281,17 @@ float *SCULPT_boundary_automasking_init(Object *ob,
   int *edge_distance = (int *)MEM_callocN(sizeof(int) * totvert, "automask_factor");
 
   for (int i : IndexRange(totvert)) {
+    PBVHVertRef vertex = BKE_pbvh_index_to_vertex(ss->pbvh, i);
+
     edge_distance[i] = EDGE_DISTANCE_INF;
     switch (mode) {
       case AUTOMASK_INIT_BOUNDARY_EDGES:
-        if (SCULPT_vertex_is_boundary(ss, i)) {
+        if (SCULPT_vertex_is_boundary(ss, vertex)) {
           edge_distance[i] = 0;
         }
         break;
       case AUTOMASK_INIT_BOUNDARY_FACE_SETS:
-        if (!SCULPT_vertex_has_unique_face_set(ss, i)) {
+        if (!SCULPT_vertex_has_unique_face_set(ss, vertex)) {
           edge_distance[i] = 0;
         }
         break;
@@ -286,11 +300,13 @@ float *SCULPT_boundary_automasking_init(Object *ob,
 
   for (int propagation_it : IndexRange(propagation_steps)) {
     for (int i : IndexRange(totvert)) {
+      PBVHVertRef vertex = BKE_pbvh_index_to_vertex(ss->pbvh, i);
+
       if (edge_distance[i] != EDGE_DISTANCE_INF) {
         continue;
       }
       SculptVertexNeighborIter ni;
-      SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, i, ni) {
+      SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vertex, ni) {
         if (edge_distance[ni.index] == propagation_it) {
           edge_distance[i] = propagation_it + 1;
         }