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, 24 insertions, 22 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt_paint_color.c b/source/blender/editors/sculpt_paint/sculpt_paint_color.c
index 7e813590e21..bf64ff39ae7 100644
--- a/source/blender/editors/sculpt_paint/sculpt_paint_color.c
+++ b/source/blender/editors/sculpt_paint/sculpt_paint_color.c
@@ -80,19 +80,19 @@ static void do_color_smooth_task_cb_exec(void *__restrict userdata,
                                                                 vd.no,
                                                                 vd.fno,
                                                                 vd.mask ? *vd.mask : 0.0f,
-                                                                vd.index,
+                                                                vd.vertex,
                                                                 thread_id);
 
     float smooth_color[4];
-    SCULPT_neighbor_color_average(ss, smooth_color, vd.index);
+    SCULPT_neighbor_color_average(ss, smooth_color, vd.vertex);
     float col[4];
 
-    SCULPT_vertex_color_get(ss, vd.index, col);
+    SCULPT_vertex_color_get(ss, vd.vertex, col);
     blend_color_interpolate_float(col, col, smooth_color, fade);
-    SCULPT_vertex_color_set(ss, vd.index, col);
+    SCULPT_vertex_color_set(ss, vd.vertex, col);
 
     if (vd.mvert) {
-      BKE_pbvh_vert_mark_update(ss->pbvh, vd.index);
+      BKE_pbvh_vert_mark_update(ss->pbvh, vd.vertex);
     }
   }
   BKE_pbvh_vertex_iter_end;
@@ -151,7 +151,7 @@ static void do_paint_brush_task_cb_ex(void *__restrict userdata,
                                                           vd.no,
                                                           vd.fno,
                                                           vd.mask ? *vd.mask : 0.0f,
-                                                          vd.index,
+                                                          vd.vertex,
                                                           thread_id);
 
     /* Density. */
@@ -182,13 +182,13 @@ static void do_paint_brush_task_cb_ex(void *__restrict userdata,
     mul_v4_v4fl(buffer_color, color_buffer->color[vd.i], brush->alpha);
 
     float col[4];
-    SCULPT_vertex_color_get(ss, vd.index, col);
+    SCULPT_vertex_color_get(ss, vd.vertex, col);
     IMB_blend_color_float(col, orig_data.col, buffer_color, brush->blend);
     CLAMP4(col, 0.0f, 1.0f);
-    SCULPT_vertex_color_set(ss, vd.index, col);
+    SCULPT_vertex_color_set(ss, vd.vertex, col);
 
     if (vd.mvert) {
-      BKE_pbvh_vert_mark_update(ss->pbvh, vd.index);
+      BKE_pbvh_vert_mark_update(ss->pbvh, vd.vertex);
     }
   }
   BKE_pbvh_vertex_iter_end;
@@ -221,7 +221,7 @@ static void do_sample_wet_paint_task_cb(void *__restrict userdata,
     }
 
     float col[4];
-    SCULPT_vertex_color_get(ss, vd.index, col);
+    SCULPT_vertex_color_get(ss, vd.vertex, col);
 
     add_v4_v4(swptd->color, col);
     swptd->tot_samples++;
@@ -400,7 +400,7 @@ static void do_smear_brush_task_cb_exec(void *__restrict userdata,
                                                                 vd.no,
                                                                 vd.fno,
                                                                 vd.mask ? *vd.mask : 0.0f,
-                                                                vd.index,
+                                                                vd.vertex,
                                                                 thread_id);
 
     float current_disp[3];
@@ -409,7 +409,7 @@ static void do_smear_brush_task_cb_exec(void *__restrict userdata,
     copy_v4_v4(interp_color, ss->cache->prev_colors[vd.index]);
 
     float no[3];
-    SCULPT_vertex_normal_get(ss, vd.index, no);
+    SCULPT_vertex_normal_get(ss, vd.vertex, no);
 
     switch (brush->smear_deform_type) {
       case BRUSH_SMEAR_DEFORM_DRAG:
@@ -442,11 +442,11 @@ static void do_smear_brush_task_cb_exec(void *__restrict userdata,
      */
 
     SculptVertexNeighborIter ni2;
-    SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.index, ni2) {
-      const float *nco = SCULPT_vertex_co_get(ss, ni2.index);
+    SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, vd.vertex, ni2) {
+      const float *nco = SCULPT_vertex_co_get(ss, ni2.vertex);
 
       SculptVertexNeighborIter ni;
-      SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, ni2.index, ni) {
+      SCULPT_VERTEX_NEIGHBORS_ITER_BEGIN (ss, ni2.vertex, ni) {
         if (ni.index == vd.index) {
           continue;
         }
@@ -454,13 +454,13 @@ static void do_smear_brush_task_cb_exec(void *__restrict userdata,
         float vertex_disp[3];
         float vertex_disp_norm[3];
 
-        sub_v3_v3v3(vertex_disp, SCULPT_vertex_co_get(ss, ni.index), vd.co);
+        sub_v3_v3v3(vertex_disp, SCULPT_vertex_co_get(ss, ni.vertex), vd.co);
 
         /* Weight by how close we are to our target distance from vd.co. */
         float w = (1.0f + fabsf(len_v3(vertex_disp) / bstrength - 1.0f));
 
         /* TODO: use cotangents (or at least face areas) here. */
-        float len = len_v3v3(SCULPT_vertex_co_get(ss, ni.index), nco);
+        float len = len_v3v3(SCULPT_vertex_co_get(ss, ni.vertex), nco);
         if (len > 0.0f) {
           len = bstrength / len;
         }
@@ -502,12 +502,12 @@ static void do_smear_brush_task_cb_exec(void *__restrict userdata,
     blend_color_mix_float(interp_color, interp_color, accum);
 
     float col[4];
-    SCULPT_vertex_color_get(ss, vd.index, col);
+    SCULPT_vertex_color_get(ss, vd.vertex, col);
     blend_color_interpolate_float(col, ss->cache->prev_colors[vd.index], interp_color, fade);
-    SCULPT_vertex_color_set(ss, vd.index, col);
+    SCULPT_vertex_color_set(ss, vd.vertex, col);
 
     if (vd.mvert) {
-      BKE_pbvh_vert_mark_update(ss->pbvh, vd.index);
+      BKE_pbvh_vert_mark_update(ss->pbvh, vd.vertex);
     }
   }
   BKE_pbvh_vertex_iter_end;
@@ -522,7 +522,7 @@ static void do_smear_store_prev_colors_task_cb_exec(void *__restrict userdata,
 
   PBVHVertexIter vd;
   BKE_pbvh_vertex_iter_begin (ss->pbvh, data->nodes[n], vd, PBVH_ITER_UNIQUE) {
-    SCULPT_vertex_color_get(ss, vd.index, ss->cache->prev_colors[vd.index]);
+    SCULPT_vertex_color_get(ss, vd.vertex, ss->cache->prev_colors[vd.index]);
   }
   BKE_pbvh_vertex_iter_end;
 }
@@ -541,7 +541,9 @@ void SCULPT_do_smear_brush(Sculpt *sd, Object *ob, PBVHNode **nodes, int totnode
   if (!ss->cache->prev_colors) {
     ss->cache->prev_colors = MEM_callocN(sizeof(float[4]) * totvert, "prev colors");
     for (int i = 0; i < totvert; i++) {
-      SCULPT_vertex_color_get(ss, i, ss->cache->prev_colors[i]);
+      PBVHVertRef vertex = BKE_pbvh_index_to_vertex(ss->pbvh, i);
+
+      SCULPT_vertex_color_get(ss, vertex, ss->cache->prev_colors[i]);
     }
   }