BMesh: add check to BM_vert_pair_share_face to allow adjacent loops

Add BM_vert_pair_share_face_by_angle to avoid selecting concave splits.

1 files changed, 8 insertions, 2 deletions

diff --git a/source/blender/bmesh/operators/bmo_subdivide.c b/source/blender/bmesh/operators/bmo_subdivide.c
index e0c86564db4..8d948fbcc69 100644
--- a/source/blender/bmesh/operators/bmo_subdivide.c
+++ b/source/blender/bmesh/operators/bmo_subdivide.c
@@ -140,13 +140,19 @@ static BMEdge *connect_smallest_face(BMesh *bm, BMVert *v_a, BMVert *v_b, BMFace
 
 	/* this isn't the best thing in the world.  it doesn't handle cases where there's
 	 * multiple faces yet.  that might require a convexity test to figure out which
-	 * face is "best" and who knows what for non-manifold conditions. */
-	f = BM_vert_pair_share_face(v_a, v_b, &l_a, &l_b);
+	 * face is "best" and who knows what for non-manifold conditions.
+	 *
+	 * note: we allow adjacent here, since theres no chance this happens.
+	 */
+	f = BM_vert_pair_share_face_by_len(v_a, v_b, &l_a, &l_b, true);
+
 
 	if (f) {
 		BMFace *f_new;
 		BMLoop *l_new;
 
+		BLI_assert(!BM_loop_is_adjacent(l_a, l_b));
+
 		f_new = BM_face_split(bm, f, l_a, l_b, &l_new, NULL, false);
 		
 		if (r_f_new) *r_f_new = f_new;