diff options
Diffstat (limited to 'src/utils.c')
| -rw-r--r-- | src/utils.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/src/utils.c b/src/utils.c index 75cdd884..7e6bf6ec 100644 --- a/src/utils.c +++ b/src/utils.c @@ -14,6 +14,7 @@ #include <stdio.h> #include "utils.h" +#include "image.h" size_t skipspace(const char *s) @@ -160,3 +161,34 @@ int quaternion_valid(struct quaternion q) return 0; } + + +struct rvec quat_rot(struct rvec q, struct quaternion z) +{ + struct rvec res; + double t01, t02, t03, t11, t12, t13, t22, t23, t33; + + t01 = z.w*z.x; + t02 = z.w*z.y; + t03 = z.w*z.z; + t11 = z.x*z.x; + t12 = z.x*z.y; + t13 = z.x*z.z; + t22 = z.y*z.y; + t23 = z.y*z.z; + t33 = z.z*z.z; + + res.u = (1.0 - 2.0 * (t22 + t33)) * q.u + + (2.0 * (t12 + t03)) * q.v + + (2.0 * (t13 - t02)) * q.w; + + res.v = (2.0 * (t12 - t03)) * q.u + + (1.0 - 2.0 * (t11 + t33)) * q.v + + (2.0 * (t01 + t23)) * q.w; + + res.w = (2.0 * (t02 + t13)) * q.u + + (2.0 * (t23 - t01)) * q.v + + (1.0 - 2.0 * (t11 + t22)) * q.w; + + return res; +} |