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Cleanup: use 2d math funcs for line intersection

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Campbell Barton 2015-06-23 20:28:32 +10:00
parent 7ecb199d86
commit ec8e0336a9
2 changed files with 50 additions and 41 deletions
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2
source/blender/blenlib/BLI_math_geom.h
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@ -142,7 +142,7 @@ int isect_line_line_v2(const float a1[2], const float a2[2], const float b1[2],
int isect_line_line_v2_int(const int a1[2], const int a2[2], const int b1[2], const int b2[2]);
int isect_line_sphere_v3(const float l1[3], const float l2[3], const float sp[3], const float r, float r_p1[3], float r_p2[3]);
int isect_line_sphere_v2(const float l1[2], const float l2[2], const float sp[2], const float r, float r_p1[2], float r_p2[2]);
int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[2], const float v4[2], float vi[2]);
int isect_seg_seg_v2_point(const float v0[2], const float v1[2], const float v2[2], const float v3[2], float vi[2]);
bool isect_seg_seg_v2(const float v1[2], const float v2[2], const float v3[2], const float v4[2]);
int isect_line_line_epsilon_v3(

89
source/blender/blenlib/intern/math_geom.c
View File

@ -697,37 +697,55 @@ int isect_line_line_v2(const float v1[2], const float v2[2], const float v3[2],
* -1: collinear
* 1: intersection
*/
int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[2], const float v4[2], float vi[2])
int isect_seg_seg_v2_point(const float v0[2], const float v1[2], const float v2[2], const float v3[2], float r_vi[2])
{
float a1, a2, b1, b2, c1, c2, d;
float u, v;
float s10[2], s32[2], s30[2], d;
const float eps = 1e-6f;
const float eps_sq = eps * eps;
a1 = v2[0] - v1[0];
b1 = v4[0] - v3[0];
c1 = v1[0] - v4[0];
sub_v2_v2v2(s10, v1, v0);
sub_v2_v2v2(s32, v3, v2);
sub_v2_v2v2(s30, v3, v0);
a2 = v2[1] - v1[1];
b2 = v4[1] - v3[1];
c2 = v1[1] - v4[1];
d = cross_v2v2(s10, s32);
d = a1 * b2 - a2 * b1;
if (d != 0) {
float u, v;
if (d == 0) {
if (a1 * c2 - a2 * c1 == 0.0f && b1 * c2 - b2 * c1 == 0.0f) { /* equal lines */
float a[2], b[2], c[2];
float u2;
u = cross_v2v2(s30, s32) / d;
v = cross_v2v2(s10, s30) / d;
if (equals_v2v2(v1, v2)) {
if (len_squared_v2v2(v3, v4) > eps_sq) {
if ((u >= -eps && u <= 1.0f + eps) &&
(v >= -eps && v <= 1.0f + eps))
{
/* intersection */
madd_v2_v2v2fl(r_vi, v0, s10, u);
return 1;
}
/* out of segment intersection */
return -1;
}
else {
if ((cross_v2v2(s10, s30) == 0.0f) &&
(cross_v2v2(s32, s30) == 0.0f))
{
/* equal lines */
float s20[2];
float u_a, u_b;
if (equals_v2v2(v0, v1)) {
if (len_squared_v2v2(v2, v3) > eps_sq) {
/* use non-point segment as basis */
SWAP(const float *, v0, v2);
SWAP(const float *, v1, v3);
SWAP(const float *, v2, v4);
sub_v2_v2v2(s10, v1, v0);
sub_v2_v2v2(s30, v3, v0);
}
else { /* both of segments are points */
if (equals_v2v2(v1, v3)) { /* points are equal */
copy_v2_v2(vi, v1);
if (equals_v2v2(v0, v2)) { /* points are equal */
copy_v2_v2(r_vi, v0);
return 1;
}
@ -736,19 +754,21 @@ int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[
}
}
sub_v2_v2v2(a, v3, v1);
sub_v2_v2v2(b, v2, v1);
sub_v2_v2v2(c, v2, v1);
u = dot_v2v2(a, b) / dot_v2v2(c, c);
sub_v2_v2v2(s20, v2, v0);
sub_v2_v2v2(a, v4, v1);
u2 = dot_v2v2(a, b) / dot_v2v2(c, c);
u_a = dot_v2v2(s20, s10) / dot_v2v2(s10, s10);
u_b = dot_v2v2(s30, s10) / dot_v2v2(s10, s10);
if (u > u2) SWAP(float, u, u2);
if (u_a > u_b)
SWAP(float, u_a, u_b);
if (u > 1.0f + eps || u2 < -eps) return -1; /* non-ovlerlapping segments */
else if (max_ff(0.0f, u) == min_ff(1.0f, u2)) { /* one common point: can return result */
interp_v2_v2v2(vi, v1, v2, max_ff(0, u));
if (u_a > 1.0f + eps || u_b < -eps) {
/* non-overlapping segments */
return -1;
}
else if (max_ff(0.0f, u_a) == min_ff(1.0f, u_b)) {
/* one common point: can return result */
madd_v2_v2v2fl(r_vi, v0, s10, max_ff(0, u_a));
return 1;
}
}
@ -756,17 +776,6 @@ int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[
/* lines are collinear */
return -1;
}
u = (c2 * b1 - b2 * c1) / d;
v = (c1 * a2 - a1 * c2) / d;
if (u >= -eps && u <= 1.0f + eps && v >= -eps && v <= 1.0f + eps) { /* intersection */
interp_v2_v2v2(vi, v1, v2, u);
return 1;
}
/* out of segment intersection */
return -1;
}
bool isect_seg_seg_v2(const float v1[2], const float v2[2], const float v3[2], const float v4[2])