diff --git a/source/blender/editors/mesh/editmesh_knife.c b/source/blender/editors/mesh/editmesh_knife.c index f3745ed72fb..f62fdf70192 100644 --- a/source/blender/editors/mesh/editmesh_knife.c +++ b/source/blender/editors/mesh/editmesh_knife.c @@ -1319,18 +1319,59 @@ static BMElem *bm_elem_from_knife_edge(KnifeEdge *kfe) return ele_test; } +/* Do edges e1 and e2 go between exactly the same coordinates? */ +static bool coinciding_edges(BMEdge *e1, BMEdge *e2) { + float *co11, *co12, *co21, *co22; + + co11 = e1->v1->co; + co12 = e1->v2->co; + co21 = e2->v1->co; + co22 = e2->v2->co; + if ((equals_v3v3(co11, co21) && equals_v3v3(co12, co22)) || + (equals_v3v3(co11, co22) && equals_v3v3(co12, co21))) + return true; + else + return false; +} + +/* Callback used in point_is_visible to exclude hits on the faces that are the same + * as or contain the hitting element (which is in user_data). + * Also (see T44492) want to exclude hits on faces that butt up to the hitting element + * (e.g., when you double an edge by an edge split). + */ static bool bm_ray_cast_cb_elem_not_in_face_check(BMFace *f, void *user_data) { + bool ans; + BMEdge *e, *e2; + BMIter iter; + switch (((BMElem *)user_data)->head.htype) { case BM_FACE: - return (BMFace *)user_data != f; + ans = (BMFace *)user_data != f; + break; case BM_EDGE: - return !BM_edge_in_face((BMEdge *)user_data, f); + e = (BMEdge *)user_data; + ans = !BM_edge_in_face(e, f); + if (ans) { + /* Is it a boundary edge, coincident with a split edge? */ + if (BM_edge_face_count(e) == 1) { + BM_ITER_ELEM(e2, &iter, f, BM_EDGES_OF_FACE) { + if (coinciding_edges(e, e2)) { + ans = false; + break; + } + } + } + } + break; case BM_VERT: - return !BM_vert_in_face((BMVert *)user_data, f); + ans = !BM_vert_in_face((BMVert *)user_data, f); + break; default: - return true; + ans = true; + break; } + return ans; }