istereo: libs/vmath/quat

istereo

added options panel, also added the xib files to the repository as they're needed

author	John Tsiombikas <nuclear@member.fsf.org>
date	Fri, 09 Sep 2011 10:03:42 +0300
parents
children	ff055bff6a15

rev	line source
nuclear@28	1 #include <stdio.h>
nuclear@28	2 #include <math.h>
nuclear@28	3 #include "quat.h"
nuclear@28	4
nuclear@28	5 void quat_print(FILE *fp, quat_t q)
nuclear@28	6 {
nuclear@28	7 fprintf(fp, "([ %.4f %.4f %.4f ] %.4f)", q.x, q.y, q.z, q.w);
nuclear@28	8 }
nuclear@28	9
nuclear@28	10 quat_t quat_rotate(quat_t q, scalar_t angle, scalar_t x, scalar_t y, scalar_t z)
nuclear@28	11 {
nuclear@28	12 quat_t rq;
nuclear@28	13 scalar_t half_angle = angle * 0.5;
nuclear@28	14 scalar_t sin_half = sin(half_angle);
nuclear@28	15
nuclear@28	16 rq.w = cos(half_angle);
nuclear@28	17 rq.x = x * sin_half;
nuclear@28	18 rq.y = y * sin_half;
nuclear@28	19 rq.z = z * sin_half;
nuclear@28	20
nuclear@28	21 return quat_mul(q, rq);
nuclear@28	22 }
nuclear@28	23
nuclear@28	24 quat_t quat_rotate_quat(quat_t q, quat_t rotq)
nuclear@28	25 {
nuclear@28	26 return quat_mul(quat_mul(rotq, q), quat_conjugate(rotq));
nuclear@28	27 }
nuclear@28	28
nuclear@28	29 quat_t quat_slerp(quat_t q1, quat_t q2, scalar_t t)
nuclear@28	30 {
nuclear@28	31 quat_t res;
nuclear@28	32 scalar_t angle = acos(q1.w * q2.w + q1.x * q2.x + q1.y * q2.y + q1.z * q2.z);
nuclear@28	33 scalar_t a = sin((1.0f - t) * angle);
nuclear@28	34 scalar_t b = sin(t * angle);
nuclear@28	35 scalar_t c = sin(angle);
nuclear@28	36
nuclear@28	37 res.x = (q1.x * a + q2.x * b) / c;
nuclear@28	38 res.y = (q1.y * a + q2.y * b) / c;
nuclear@28	39 res.z = (q1.z * a + q2.z * b) / c;
nuclear@28	40 res.w = (q1.w * a + q2.w * b) / c;
nuclear@28	41 return quat_normalize(res);
nuclear@28	42 }