Fix T37837: mirror modifier merge does not place vertices at the center.

This was broken since BMesh.

1 files changed, 4 insertions, 0 deletions

diff --git a/source/blender/modifiers/intern/MOD_mirror.c b/source/blender/modifiers/intern/MOD_mirror.c
index 1b9fcd9f34e..ec09b80dc5a 100644
--- a/source/blender/modifiers/intern/MOD_mirror.c
+++ b/source/blender/modifiers/intern/MOD_mirror.c
@@ -187,6 +187,10 @@ static DerivedMesh *doMirrorOnAxis(MirrorModifierData *mmd,
 			if (UNLIKELY(len_squared_v3v3(mv_prev->co, mv->co) < tolerance_sq)) {
 				*vtmap_a = maxVerts + i;
 				tot_vtargetmap++;
+
+				/* average location */
+				mid_v3_v3v3(mv->co, mv_prev->co, mv->co);
+				copy_v3_v3(mv_prev->co, mv->co);
 			}
 			else {
 				*vtmap_a = -1;