obs-studio/libobs/graphics/axisang.c

39 lines
1.3 KiB
C

/******************************************************************************
Copyright (C) 2013 by Hugh Bailey <obs.jim@gmail.com>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/
#include "axisang.h"
#include "quat.h"
void axisang_from_quat(struct axisang *dst, const struct quat *q)
{
float len, leni;
len = q->x*q->x + q->y*q->y + q->z*q->z;
if (!close_float(len, 0.0f, EPSILON)) {
leni = 1.0f/sqrtf(len);
dst->x = q->x * leni;
dst->y = q->y * leni;
dst->z = q->z * leni;
dst->w = acosf(q->w)*2.0f;
} else {
dst->x = 0.0f;
dst->y = 0.0f;
dst->z = 0.0f;
dst->w = 0.0f;
}
}