Fix wrong coordinates being read when using the sculpt API

The coordinates should be read from the PBVH when using deform modifiers.
This is needed for the cloth brush to work with subdivisions, as it reads the
vertex coordinates using this function when building and updating the
constraints.

Reviewed By: jbakker

Differential Revision: https://developer.blender.org/D6967

1 files changed, 9 insertions, 2 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 7c51ddd597a..55ddc82c3f8 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -129,8 +129,15 @@ static int sculpt_vertex_count_get(SculptSession *ss)
 const float *sculpt_vertex_co_get(SculptSession *ss, int index)
 {
   switch (BKE_pbvh_type(ss->pbvh)) {
-    case PBVH_FACES:
-      return ss->mvert[index].co;
+    case PBVH_FACES: {
+      if (ss->shapekey_active || ss->deform_modifiers_active) {
+        const MVert *mverts = BKE_pbvh_get_verts(ss->pbvh);
+        return mverts[index].co;
+      }
+      else {
+        return ss->mvert[index].co;
+      }
+    }
     case PBVH_BMESH:
       return BM_vert_at_index(BKE_pbvh_get_bmesh(ss->pbvh), index)->co;
     case PBVH_GRIDS: {