[Bf-blender-cvs] [3fdd092649c] master: Cleanup: face-center mesh calculation

[Campbell Barton]

Commit: 3fdd092649c038550776970ee7ded56afc3e94ab
Author: Campbell Barton
Date:   Fri Jul 10 12:38:28 2020 +1000
Branches: master
https://developer.blender.org/rB3fdd092649c038550776970ee7ded56afc3e94ab

Cleanup: face-center mesh calculation

Loop over faces and calculate their centers instead of zeroing the
face center array and accumulating all faces vertex corners.

Move subsurf face center extraction into it's own loop since it works
differently.

===================================================================

M	source/blender/draw/intern/draw_cache_extract_mesh.c

===================================================================

diff --git a/source/blender/draw/intern/draw_cache_extract_mesh.c b/source/blender/draw/intern/draw_cache_extract_mesh.c
index 5b7dbf4e6e1..a27ee90b148 100644
--- a/source/blender/draw/intern/draw_cache_extract_mesh.c
+++ b/source/blender/draw/intern/draw_cache_extract_mesh.c
@@ -4386,10 +4386,6 @@ static void *extract_fdots_pos_init(const MeshRenderData *mr, void *buf)
   GPUVertBuf *vbo = buf;
   GPU_vertbuf_init_with_format(vbo, &format);
   GPU_vertbuf_data_alloc(vbo, mr->poly_len);
-  if (!mr->use_subsurf_fdots) {
-    /* Clear so we can accumulate on it. */
-    memset(vbo->data, 0x0, mr->poly_len * vbo->format.stride);
-  }
   return vbo->data;
 }
 
@@ -4398,12 +4394,20 @@ static void extract_fdots_pos_iter_poly_bm(const MeshRenderData *mr,
                                            void *data)
 {
   float(*center)[3] = data;
-  EXTRACT_POLY_AND_LOOP_FOREACH_BM_BEGIN(l, l_index, params, mr)
+
+  EXTRACT_POLY_FOREACH_BM_BEGIN(f, f_index, params, mr)
   {
-    float w = 1.0f / (float)l->f->len;
-    madd_v3_v3fl(center[BM_elem_index_get(l->f)], bm_vert_co_get(mr, l->v), w);
+    float *co = center[f_index];
+    zero_v3(co);
+
+    BMLoop *l_iter, *l_first;
+    l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+    do {
+      add_v3_v3(co, bm_vert_co_get(mr, l_iter->v));
+    } while ((l_iter = l_iter->next) != l_first);
+    mul_v3_fl(co, 1.0f / (float)f->len);
   }
-  EXTRACT_POLY_AND_LOOP_FOREACH_BM_END(l);
+  EXTRACT_POLY_FOREACH_BM_END;
 }
 
 static void extract_fdots_pos_iter_poly_mesh(const MeshRenderData *mr,
@@ -4411,20 +4415,34 @@ static void extract_fdots_pos_iter_poly_mesh(const MeshRenderData *mr,
                                              void *data)
 {
   float(*center)[3] = (float(*)[3])data;
-  EXTRACT_POLY_AND_LOOP_FOREACH_MESH_BEGIN(mp, mp_index, ml, ml_index, params, mr)
-  {
-    const MVert *mv = &mr->mvert[ml->v];
-    if (mr->use_subsurf_fdots) {
+  const MVert *mvert = mr->mvert;
+  const MLoop *mloop = mr->mloop;
+
+  if (mr->use_subsurf_fdots) {
+    EXTRACT_POLY_AND_LOOP_FOREACH_MESH_BEGIN(mp, mp_index, ml, ml_index, params, mr)
+    {
+      const MVert *mv = &mr->mvert[ml->v];
       if (mv->flag & ME_VERT_FACEDOT) {
         copy_v3_v3(center[mp_index], mv->co);
       }
     }
-    else {
-      float w = 1.0f / (float)mp->totloop;
-      madd_v3_v3fl(center[mp_index], mv->co, w);
+    EXTRACT_POLY_AND_LOOP_FOREACH_MESH_END;
+  }
+  else {
+    EXTRACT_POLY_FOREACH_MESH_BEGIN(mp, mp_index, params, mr)
+    {
+      float *co = center[mp_index];
+      zero_v3(co);
+
+      const MLoop *ml = &mloop[mp->loopstart];
+      for (int i = 0; i < mp->totloop; i++, ml++) {
+        const MVert *mv = &mvert[ml->v];
+        add_v3_v3(center[mp_index], mv->co);
+      }
+      mul_v3_fl(co, 1.0f / (float)mp->totloop);
     }
+    EXTRACT_POLY_FOREACH_MESH_END;
   }
-  EXTRACT_POLY_AND_LOOP_FOREACH_MESH_END;
 }
 
 static const MeshExtract extract_fdots_pos = {