diff options
Diffstat (limited to 'source/blender/blenlib/intern/math_geom.c')
| -rw-r--r-- | source/blender/blenlib/intern/math_geom.c | 141 |
1 files changed, 137 insertions, 4 deletions
diff --git a/source/blender/blenlib/intern/math_geom.c b/source/blender/blenlib/intern/math_geom.c index 96ed788a49f..fc329fe1bf1 100644 --- a/source/blender/blenlib/intern/math_geom.c +++ b/source/blender/blenlib/intern/math_geom.c @@ -37,8 +37,6 @@ #include "BLI_memarena.h" #include "BLI_utildefines.h" -static float lambda_cp_line(const float p[3], const float l1[3], const float l2[3]); - /********************************** Polygons *********************************/ void cent_tri_v3(float cent[3], const float v1[3], const float v2[3], const float v3[3]) @@ -349,6 +347,133 @@ int isect_seg_seg_v2_point(const float v1[2], const float v2[2], const float v3[ return -1; } +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]) +{ + /* l1: coordinates (point of line) + * l2: coordinates (point of line) + * sp, r: coordinates and radius (sphere) + * r_p1, r_p2: return intersection coordinates + */ + + + /* adapted for use in blender by Campbell Barton - 2011 + * + * atelier iebele abel - 2001 + * atelier@iebele.nl + * http://www.iebele.nl + * + * sphere_line_intersection function adapted from: + * http://astronomy.swin.edu.au/pbourke/geometry/sphereline + * Paul Bourke pbourke@swin.edu.au + */ + + const float ldir[3]= { + l2[0] - l1[0], + l2[1] - l1[1], + l2[2] - l1[2] + }; + + const float a= dot_v3v3(ldir, ldir); + + const float b= 2.0f * + (ldir[0] * (l1[0] - sp[0]) + + ldir[1] * (l1[1] - sp[1]) + + ldir[2] * (l1[2] - sp[2])); + + const float c= + dot_v3v3(sp, sp) + + dot_v3v3(l1, l1) - + (2.0f * dot_v3v3(sp, l1)) - + (r * r); + + const float i = b * b - 4.0f * a * c; + + float mu; + + if (i < 0.0f) { + /* no intersections */ + return 0; + } + else if (i == 0.0f) { + /* one intersection */ + mu = -b / (2.0f * a); + madd_v3_v3v3fl(r_p1, l1, ldir, mu); + return 1; + } + else if (i > 0.0) { + const float i_sqrt= sqrt(i); /* avoid calc twice */ + + /* first intersection */ + mu = (-b + i_sqrt) / (2.0f * a); + madd_v3_v3v3fl(r_p1, l1, ldir, mu); + + /* second intersection */ + mu = (-b - i_sqrt) / (2.0f * a); + madd_v3_v3v3fl(r_p2, l1, ldir, mu); + return 2; + } + else { + /* math domain error - nan */ + return -1; + } +} + +/* keep in sync with isect_line_sphere_v3 */ +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]) +{ + const float ldir[2]= { + l2[0] - l1[0], + l2[1] - l1[1] + }; + + const float a= dot_v2v2(ldir, ldir); + + const float b= 2.0f * + (ldir[0] * (l1[0] - sp[0]) + + ldir[1] * (l1[1] - sp[1])); + + const float c= + dot_v2v2(sp, sp) + + dot_v2v2(l1, l1) - + (2.0f * dot_v2v2(sp, l1)) - + (r * r); + + const float i = b * b - 4.0f * a * c; + + float mu; + + if (i < 0.0f) { + /* no intersections */ + return 0; + } + else if (i == 0.0f) { + /* one intersection */ + mu = -b / (2.0f * a); + madd_v2_v2v2fl(r_p1, l1, ldir, mu); + return 1; + } + else if (i > 0.0) { + const float i_sqrt= sqrt(i); /* avoid calc twice */ + + /* first intersection */ + mu = (-b + i_sqrt) / (2.0f * a); + madd_v2_v2v2fl(r_p1, l1, ldir, mu); + + /* second intersection */ + mu = (-b - i_sqrt) / (2.0f * a); + madd_v2_v2v2fl(r_p2, l1, ldir, mu); + return 2; + } + else { + /* math domain error - nan */ + return -1; + } +} + /* -1: colliniar 1: intersection @@ -668,7 +793,7 @@ int isect_line_plane_v3(float out[3], const float l1[3], const float l2[3], cons add_v3_v3v3(l1_plane, l1, p_no); - dist = lambda_cp_line(plane_co, l1, l1_plane); + dist = line_point_factor_v3(plane_co, l1, l1_plane); /* treat line like a ray, when 'no_flip' is set */ if(no_flip && dist < 0.0f) { @@ -1118,7 +1243,7 @@ float closest_to_line_v2(float cp[2],const float p[2], const float l1[2], const } /* little sister we only need to know lambda */ -static float lambda_cp_line(const float p[3], const float l1[3], const float l2[3]) +float line_point_factor_v3(const float p[3], const float l1[3], const float l2[3]) { float h[3],u[3]; sub_v3_v3v3(u, l2, l1); @@ -1126,6 +1251,14 @@ static float lambda_cp_line(const float p[3], const float l1[3], const float l2[ return(dot_v3v3(u,h)/dot_v3v3(u,u)); } +float line_point_factor_v2(const float p[2], const float l1[2], const float l2[2]) +{ + float h[2], u[2]; + sub_v2_v2v2(u, l2, l1); + sub_v2_v2v2(h, p, l1); + return(dot_v2v2(u, h)/dot_v2v2(u, u)); +} + /* Similar to LineIntersectsTriangleUV, except it operates on a quad and in 2d, assumes point is in quad */ void isect_point_quad_uv_v2(const float v0[2], const float v1[2], const float v2[2], const float v3[2], const float pt[2], float *uv) { |