axmol/external/chipmunk/src/cpVect.c

56 lines
1.9 KiB
C

/* Copyright (c) 2007 Scott Lembcke
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <stdio.h>
#include "chipmunk_private.h"
inline cpVect
cpvslerp(const cpVect v1, const cpVect v2, const cpFloat t)
{
cpFloat dot = cpvdot(cpvnormalize(v1), cpvnormalize(v2));
cpFloat omega = cpfacos(cpfclamp(dot, -1.0f, 1.0f));
if(omega == 0.0){
return v1;
} else {
cpFloat denom = 1.0f/cpfsin(omega);
return cpvadd(cpvmult(v1, cpfsin((1.0f - t)*omega)*denom), cpvmult(v2, cpfsin(t*omega)*denom));
}
}
cpVect
cpvslerpconst(const cpVect v1, const cpVect v2, const cpFloat a)
{
cpFloat dot = cpvdot(cpvnormalize(v1), cpvnormalize(v2));
cpFloat omega = cpfacos(cpfclamp(dot, -1.0f, 1.0f));
return cpvslerp(v1, v2, cpfmin(a, omega)/omega);
}
char*
cpvstr(const cpVect v)
{
static char str[256];
sprintf(str, "(% .3f, % .3f)", v.x, v.y);
return str;
}