Calculation of the center and normal for sculpting would ignore whether the sculpting tool is using the current vertex positions/normals or the positions/normals from before the current edit. Most of the time this will lead to subtle and hard to predict differences from what a user might expect. There was sum testing and discussion about at the end of last summer and even some screen shots showing the difference. I'm going to go ahead and apply this since I do not think it is controversial.

1 files changed, 2 insertions, 2 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index 4cd95dca9f9..272475194ee 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -1688,7 +1688,7 @@ static void calc_flatten_center(Sculpt *sd, Object *ob, PBVHNode **nodes, int to
 		if(ss->cache->original) {
 			BLI_pbvh_vertex_iter_begin(ss->pbvh, nodes[n], vd, PBVH_ITER_UNIQUE) {
 				if(sculpt_brush_test_fast(&test, unode->co[vd.i])) {
-					add_v3_v3(private_fc, vd.co);
+					add_v3_v3(private_fc, unode->co[vd.i]);
 					private_count++;
 				}
 			}
@@ -1758,7 +1758,7 @@ static void calc_area_normal_and_flatten_center(Sculpt *sd, Object *ob, PBVHNode
 					add_norm_if(ss->cache->view_normal, private_an, private_out_flip, fno);
 
 					// fc
-					add_v3_v3(private_fc, vd.co);
+					add_v3_v3(private_fc, unode->co[vd.i]);
 					private_count++;
 				}
 			}