diff options
Diffstat (limited to 'source/blender/blenlib/intern/arithb.c')
| -rw-r--r-- | source/blender/blenlib/intern/arithb.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/source/blender/blenlib/intern/arithb.c b/source/blender/blenlib/intern/arithb.c index c20794953b9..e7a31e37581 100644 --- a/source/blender/blenlib/intern/arithb.c +++ b/source/blender/blenlib/intern/arithb.c @@ -2981,6 +2981,29 @@ void VecBisect3(float *out, float *v1, float *v2, float *v3) Normalize(out); } +/* Returns a reflection vector from a vector and a normal vector +reflect = vec - ((2 * DotVecs(vec, mirror)) * mirror) +*/ +void VecReflect(float *out, float *v1, float *v2) +{ + float vec[3], normal[3]; + float reflect[3] = {0.0f, 0.0f, 0.0f}; + float dot2; + + VecCopyf(vec, v1); + VecCopyf(normal, v2); + + Normalize(normal); + + dot2 = 2 * Inpf(vec, normal); + + reflect[0] = vec[0] - (dot2 * normal[0]); + reflect[1] = vec[1] - (dot2 * normal[1]); + reflect[2] = vec[2] - (dot2 * normal[2]); + + VecCopyf(out, reflect); +} + /* Return the angle in degrees between vecs 1-2 and 2-3 in degrees If v1 is a shoulder, v2 is the elbow and v3 is the hand, this would return the angle at the elbow */ |