istereo2
diff libs/vmath/quat_c.c @ 2:81d35769f546
added the tunnel effect source
author | John Tsiombikas <nuclear@member.fsf.org> |
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date | Sat, 19 Sep 2015 05:51:51 +0300 |
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1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/libs/vmath/quat_c.c Sat Sep 19 05:51:51 2015 +0300 1.3 @@ -0,0 +1,61 @@ 1.4 +/* 1.5 +libvmath - a vector math library 1.6 +Copyright (C) 2004-2011 John Tsiombikas <nuclear@member.fsf.org> 1.7 + 1.8 +This program is free software: you can redistribute it and/or modify 1.9 +it under the terms of the GNU Lesser General Public License as published 1.10 +by the Free Software Foundation, either version 3 of the License, or 1.11 +(at your option) any later version. 1.12 + 1.13 +This program is distributed in the hope that it will be useful, 1.14 +but WITHOUT ANY WARRANTY; without even the implied warranty of 1.15 +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1.16 +GNU Lesser General Public License for more details. 1.17 + 1.18 +You should have received a copy of the GNU Lesser General Public License 1.19 +along with this program. If not, see <http://www.gnu.org/licenses/>. 1.20 +*/ 1.21 + 1.22 + 1.23 +#include <stdio.h> 1.24 +#include <math.h> 1.25 +#include "quat.h" 1.26 + 1.27 +void quat_print(FILE *fp, quat_t q) 1.28 +{ 1.29 + fprintf(fp, "([ %.4f %.4f %.4f ] %.4f)", q.x, q.y, q.z, q.w); 1.30 +} 1.31 + 1.32 +quat_t quat_rotate(quat_t q, scalar_t angle, scalar_t x, scalar_t y, scalar_t z) 1.33 +{ 1.34 + quat_t rq; 1.35 + scalar_t half_angle = angle * 0.5; 1.36 + scalar_t sin_half = sin(half_angle); 1.37 + 1.38 + rq.w = cos(half_angle); 1.39 + rq.x = x * sin_half; 1.40 + rq.y = y * sin_half; 1.41 + rq.z = z * sin_half; 1.42 + 1.43 + return quat_mul(q, rq); 1.44 +} 1.45 + 1.46 +quat_t quat_rotate_quat(quat_t q, quat_t rotq) 1.47 +{ 1.48 + return quat_mul(quat_mul(rotq, q), quat_conjugate(rotq)); 1.49 +} 1.50 + 1.51 +quat_t quat_slerp(quat_t q1, quat_t q2, scalar_t t) 1.52 +{ 1.53 + quat_t res; 1.54 + scalar_t angle = acos(q1.w * q2.w + q1.x * q2.x + q1.y * q2.y + q1.z * q2.z); 1.55 + scalar_t a = sin((1.0f - t) * angle); 1.56 + scalar_t b = sin(t * angle); 1.57 + scalar_t c = sin(angle); 1.58 + 1.59 + res.x = (q1.x * a + q2.x * b) / c; 1.60 + res.y = (q1.y * a + q2.y * b) / c; 1.61 + res.z = (q1.z * a + q2.z * b) / c; 1.62 + res.w = (q1.w * a + q2.w * b) / c; 1.63 + return quat_normalize(res); 1.64 +}