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, 6 insertions, 4 deletions

diff --git a/source/blender/editors/sculpt_paint/paint_mask.c b/source/blender/editors/sculpt_paint/paint_mask.c
index 89bbf2a3c92..a5389f7fd83 100644
--- a/source/blender/editors/sculpt_paint/paint_mask.c
+++ b/source/blender/editors/sculpt_paint/paint_mask.c
@@ -663,7 +663,7 @@ static bool sculpt_gesture_is_effected_lasso(SculptGestureContext *sgcontext, co
 static bool sculpt_gesture_is_vertex_effected(SculptGestureContext *sgcontext, PBVHVertexIter *vd)
 {
   float vertex_normal[3];
-  SCULPT_vertex_normal_get(sgcontext->ss, vd->index, vertex_normal);
+  SCULPT_vertex_normal_get(sgcontext->ss, vd->vertex, vertex_normal);
   float dot = dot_v3v3(sgcontext->view_normal, vertex_normal);
   const bool is_effected_front_face = !(sgcontext->front_faces_only && dot < 0.0f);
 
@@ -743,7 +743,7 @@ static void face_set_gesture_apply_task_cb(void *__restrict userdata,
 
   BKE_pbvh_vertex_iter_begin (sgcontext->ss->pbvh, node, vd, PBVH_ITER_UNIQUE) {
     if (sculpt_gesture_is_vertex_effected(sgcontext, &vd)) {
-      SCULPT_vertex_face_set_set(sgcontext->ss, vd.index, face_set_operation->new_face_set_id);
+      SCULPT_vertex_face_set_set(sgcontext->ss, vd.vertex, face_set_operation->new_face_set_id);
       any_updated = true;
     }
   }
@@ -1025,7 +1025,9 @@ static void sculpt_gesture_trim_calculate_depth(SculptGestureContext *sgcontext)
   trim_operation->depth_back = -FLT_MAX;
 
   for (int i = 0; i < totvert; i++) {
-    const float *vco = SCULPT_vertex_co_get(ss, i);
+    PBVHVertRef vertex = BKE_pbvh_index_to_vertex(ss->pbvh, i);
+
+    const float *vco = SCULPT_vertex_co_get(ss, vertex);
     /* Convert the coordinates to world space to calculate the depth. When generating the trimming
      * mesh, coordinates are first calculated in world space, then converted to object space to
      * store them. */
@@ -1437,7 +1439,7 @@ static void project_line_gesture_apply_task_cb(void *__restrict userdata,
     }
     add_v3_v3(vd.co, disp);
     if (vd.mvert) {
-      BKE_pbvh_vert_mark_update(sgcontext->ss->pbvh, vd.index);
+      BKE_pbvh_vert_mark_update(sgcontext->ss->pbvh, vd.vertex);
     }
     any_updated = true;
   }