Fix T39685: triangulation modifier creates zero-area faces

This commit is contained in:
Campbell Barton 2014-04-16 01:17:00 +10:00
parent 43b7dac427
commit 5c4bb81e49

@ -133,10 +133,11 @@ static float bm_edge_calc_rotate_beauty__area(
/* not a loop (only to be able to break out) */
do {
float v1_xy[2], v2_xy[2], v3_xy[2], v4_xy[2];
bool is_zero_a, is_zero_b;
/* first get the 2d values */
{
bool is_zero_a, is_zero_b;
float no_a[3], no_b[3];
float no[3];
float axis_mat[3][3];
@ -146,23 +147,20 @@ static float bm_edge_calc_rotate_beauty__area(
(ELEM3(v3, v1, v2, v4) == false) &&
(ELEM3(v4, v1, v2, v3) == false));
is_zero_a = area_tri_v3(v2, v3, v4) <= FLT_EPSILON;
is_zero_b = area_tri_v3(v2, v4, v1) <= FLT_EPSILON;
is_zero_a = (normal_tri_v3(no_a, v2, v3, v4) <= FLT_EPSILON);
is_zero_b = (normal_tri_v3(no_b, v2, v4, v1) <= FLT_EPSILON);
if (LIKELY(is_zero_a == false && is_zero_b == false)) {
float no_a[3], no_b[3];
normal_tri_v3(no_a, v2, v3, v4); /* a */
normal_tri_v3(no_b, v2, v4, v1); /* b */
add_v3_v3v3(no, no_a, no_b);
if (UNLIKELY(normalize_v3(no) <= FLT_EPSILON)) {
break;
}
}
else if (is_zero_a == false) {
normal_tri_v3(no, v2, v3, v4); /* a */
copy_v3_v3(no, no_a);
}
else if (is_zero_b == false) {
normal_tri_v3(no, v2, v4, v1); /* b */
copy_v3_v3(no, no_b);
}
else {
/* both zero area, no useful normal can be calculated */
@ -180,7 +178,32 @@ static float bm_edge_calc_rotate_beauty__area(
// printf("%p %p %p %p - %p %p\n", v1, v2, v3, v4, e->l->f, e->l->radial_next->f);
if (is_quad_convex_v2(v1_xy, v2_xy, v3_xy, v4_xy)) {
if (is_zero_a == false && is_zero_b == false) {
/* both tri's are valid, check we make a concave quad */
if (!is_quad_convex_v2(v1_xy, v2_xy, v3_xy, v4_xy)) {
break;
}
}
else {
/* one of the tri's was degenerate, chech we're not rotating
* into a different degenerate shape or flipping the face */
float area_a, area_b;
area_a = area_tri_signed_v2(v1_xy, v2_xy, v3_xy);
area_b = area_tri_signed_v2(v1_xy, v3_xy, v4_xy);
if ((fabsf(area_a) <= FLT_EPSILON) || (fabsf(area_b) <= FLT_EPSILON)) {
/* one of the new rotations is degenerate */
break;
}
if ((area_a >= 0.0f) != (area_b >= 0.0f)) {
/* rotation would cause flipping */
break;
}
}
{
/* testing rule: the area divided by the perimeter,
* check if (1-3) beats the existing (2-4) edge rotation */
float area_a, area_b;
@ -249,7 +272,8 @@ static float bm_edge_calc_rotate_beauty__angle(
}
float BM_verts_calc_rotate_beauty(
const BMVert *v1, const BMVert *v2, const BMVert *v3, const BMVert *v4, const short flag, const short method)
const BMVert *v1, const BMVert *v2, const BMVert *v3, const BMVert *v4,
const short flag, const short method)
{
/* not a loop (only to be able to break out) */
do {