merge trunk 17122:17213

[blender-staging.git] / source / blender / blenlib / intern / arithb.c

diff --git a/source/blender/blenlib/intern/arithb.c b/source/blender/blenlib/intern/arithb.c
index 149d3cf1f8f5bc65413d18a6346fae0a008657c0..0db87a819bd850ab08a62d0fc7539ff590c983c9 100644 (file)
--- a/source/blender/blenlib/intern/arithb.c
+++ b/source/blender/blenlib/intern/arithb.c
@@ -4238,6 +4238,67 @@ int LineIntersectLine(float v1[3], float v2[3], float v3[3], float v4[3], float
        }
 } 
 
+/* Intersection point strictly between the two lines
+ * 0 when no intersection is found 
+ * */
+int LineIntersectLineStrict(float v1[3], float v2[3], float v3[3], float v4[3], float vi[3], float *lambda)
+{
+       float a[3], b[3], c[3], ab[3], cb[3], ca[3], dir1[3], dir2[3];
+       float d;
+       float d1;
+       
+       VecSubf(c, v3, v1);
+       VecSubf(a, v2, v1);
+       VecSubf(b, v4, v3);
+
+       VecCopyf(dir1, a);
+       Normalize(dir1);
+       VecCopyf(dir2, b);
+       Normalize(dir2);
+       d = Inpf(dir1, dir2);
+       if (d == 1.0f || d == -1.0f || d == 0) {
+               /* colinear or one vector is zero-length*/
+               return 0;
+       }
+       
+       d1 = d;
+
+       Crossf(ab, a, b);
+       d = Inpf(c, ab);
+
+       /* test if the two lines are coplanar */
+       if (d > -0.000001f && d < 0.000001f) {
+               float f1, f2;
+               Crossf(cb, c, b);
+               Crossf(ca, c, a);
+
+               f1 = Inpf(cb, ab) / Inpf(ab, ab);
+               f2 = Inpf(ca, ab) / Inpf(ab, ab);
+               
+               if (f1 >= 0 && f1 <= 1 &&
+                       f2 >= 0 && f2 <= 1)
+               {
+                       VecMulf(a, f1);
+                       VecAddf(vi, v1, a);
+                       
+                       if (lambda != NULL)
+                       {
+                               *lambda = f1;
+                       }
+                       
+                       return 1; /* intersection found */
+               }
+               else
+               {
+                       return 0;
+               }
+       }
+       else
+       {
+               return 0;
+       }
+} 
+
 int AabbIntersectAabb(float min1[3], float max1[3], float min2[3], float max2[3])
 {
        return (min1[0]<max2[0] && min1[1]<max2[1] && min1[2]<max2[2] &&