halflife25-sdk/utils/common/mathlib.c
2013-08-30 13:34:05 -07:00

351 lines
7.9 KiB
C

/***
*
* Copyright (c) 1996-2002, Valve LLC. All rights reserved.
*
* This product contains software technology licensed from Id
* Software, Inc. ("Id Technology"). Id Technology (c) 1996 Id Software, Inc.
* All Rights Reserved.
*
****/
// mathlib.c -- math primitives
#pragma warning( disable : 4244 )
#pragma warning( disable : 4237 )
#pragma warning( disable : 4305 )
#include "cmdlib.h"
#include "mathlib.h"
vec3_t vec3_origin = {0,0,0};
double VectorLength(vec3_t v)
{
int i;
double length;
length = 0;
for (i=0 ; i< 3 ; i++)
length += v[i]*v[i];
length = sqrt (length); // FIXME
return length;
}
int VectorCompare (vec3_t v1, vec3_t v2)
{
int i;
for (i=0 ; i<3 ; i++)
if (fabs(v1[i]-v2[i]) > EQUAL_EPSILON)
return false;
return true;
}
vec_t Q_rint (vec_t in)
{
return floor (in + 0.5);
}
void VectorMA (vec3_t va, double scale, vec3_t vb, vec3_t vc)
{
vc[0] = va[0] + scale*vb[0];
vc[1] = va[1] + scale*vb[1];
vc[2] = va[2] + scale*vb[2];
}
void CrossProduct (vec3_t v1, vec3_t v2, vec3_t cross)
{
cross[0] = v1[1]*v2[2] - v1[2]*v2[1];
cross[1] = v1[2]*v2[0] - v1[0]*v2[2];
cross[2] = v1[0]*v2[1] - v1[1]*v2[0];
}
vec_t _DotProduct (vec3_t v1, vec3_t v2)
{
return v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2];
}
void _VectorSubtract (vec3_t va, vec3_t vb, vec3_t out)
{
out[0] = va[0]-vb[0];
out[1] = va[1]-vb[1];
out[2] = va[2]-vb[2];
}
void _VectorAdd (vec3_t va, vec3_t vb, vec3_t out)
{
out[0] = va[0]+vb[0];
out[1] = va[1]+vb[1];
out[2] = va[2]+vb[2];
}
void _VectorCopy (vec3_t in, vec3_t out)
{
out[0] = in[0];
out[1] = in[1];
out[2] = in[2];
}
void _VectorScale (vec3_t v, vec_t scale, vec3_t out)
{
out[0] = v[0] * scale;
out[1] = v[1] * scale;
out[2] = v[2] * scale;
}
vec_t VectorNormalize (vec3_t v)
{
int i;
double length;
if ( fabs(v[1] - 0.000215956) < 0.0001)
i=1;
length = 0;
for (i=0 ; i< 3 ; i++)
length += v[i]*v[i];
length = sqrt (length);
if (length == 0)
return 0;
for (i=0 ; i< 3 ; i++)
v[i] /= length;
return length;
}
void VectorInverse (vec3_t v)
{
v[0] = -v[0];
v[1] = -v[1];
v[2] = -v[2];
}
void ClearBounds (vec3_t mins, vec3_t maxs)
{
mins[0] = mins[1] = mins[2] = 99999;
maxs[0] = maxs[1] = maxs[2] = -99999;
}
void AddPointToBounds (vec3_t v, vec3_t mins, vec3_t maxs)
{
int i;
vec_t val;
for (i=0 ; i<3 ; i++)
{
val = v[i];
if (val < mins[i])
mins[i] = val;
if (val > maxs[i])
maxs[i] = val;
}
}
void AngleMatrix (const vec3_t angles, float (*matrix)[4] )
{
float angle;
float sr, sp, sy, cr, cp, cy;
angle = angles[2] * (Q_PI*2 / 360);
sy = sin(angle);
cy = cos(angle);
angle = angles[1] * (Q_PI*2 / 360);
sp = sin(angle);
cp = cos(angle);
angle = angles[0] * (Q_PI*2 / 360);
sr = sin(angle);
cr = cos(angle);
// matrix = (Z * Y) * X
matrix[0][0] = cp*cy;
matrix[1][0] = cp*sy;
matrix[2][0] = -sp;
matrix[0][1] = sr*sp*cy+cr*-sy;
matrix[1][1] = sr*sp*sy+cr*cy;
matrix[2][1] = sr*cp;
matrix[0][2] = (cr*sp*cy+-sr*-sy);
matrix[1][2] = (cr*sp*sy+-sr*cy);
matrix[2][2] = cr*cp;
matrix[0][3] = 0.0;
matrix[1][3] = 0.0;
matrix[2][3] = 0.0;
}
void AngleIMatrix (const vec3_t angles, float matrix[3][4] )
{
float angle;
float sr, sp, sy, cr, cp, cy;
angle = angles[2] * (Q_PI*2 / 360);
sy = sin(angle);
cy = cos(angle);
angle = angles[1] * (Q_PI*2 / 360);
sp = sin(angle);
cp = cos(angle);
angle = angles[0] * (Q_PI*2 / 360);
sr = sin(angle);
cr = cos(angle);
// matrix = (Z * Y) * X
matrix[0][0] = cp*cy;
matrix[0][1] = cp*sy;
matrix[0][2] = -sp;
matrix[1][0] = sr*sp*cy+cr*-sy;
matrix[1][1] = sr*sp*sy+cr*cy;
matrix[1][2] = sr*cp;
matrix[2][0] = (cr*sp*cy+-sr*-sy);
matrix[2][1] = (cr*sp*sy+-sr*cy);
matrix[2][2] = cr*cp;
matrix[0][3] = 0.0;
matrix[1][3] = 0.0;
matrix[2][3] = 0.0;
}
void R_ConcatTransforms (const float in1[3][4], const float in2[3][4], float out[3][4])
{
out[0][0] = in1[0][0] * in2[0][0] + in1[0][1] * in2[1][0] +
in1[0][2] * in2[2][0];
out[0][1] = in1[0][0] * in2[0][1] + in1[0][1] * in2[1][1] +
in1[0][2] * in2[2][1];
out[0][2] = in1[0][0] * in2[0][2] + in1[0][1] * in2[1][2] +
in1[0][2] * in2[2][2];
out[0][3] = in1[0][0] * in2[0][3] + in1[0][1] * in2[1][3] +
in1[0][2] * in2[2][3] + in1[0][3];
out[1][0] = in1[1][0] * in2[0][0] + in1[1][1] * in2[1][0] +
in1[1][2] * in2[2][0];
out[1][1] = in1[1][0] * in2[0][1] + in1[1][1] * in2[1][1] +
in1[1][2] * in2[2][1];
out[1][2] = in1[1][0] * in2[0][2] + in1[1][1] * in2[1][2] +
in1[1][2] * in2[2][2];
out[1][3] = in1[1][0] * in2[0][3] + in1[1][1] * in2[1][3] +
in1[1][2] * in2[2][3] + in1[1][3];
out[2][0] = in1[2][0] * in2[0][0] + in1[2][1] * in2[1][0] +
in1[2][2] * in2[2][0];
out[2][1] = in1[2][0] * in2[0][1] + in1[2][1] * in2[1][1] +
in1[2][2] * in2[2][1];
out[2][2] = in1[2][0] * in2[0][2] + in1[2][1] * in2[1][2] +
in1[2][2] * in2[2][2];
out[2][3] = in1[2][0] * in2[0][3] + in1[2][1] * in2[1][3] +
in1[2][2] * in2[2][3] + in1[2][3];
}
void VectorRotate (const vec3_t in1, const float in2[3][4], vec3_t out)
{
out[0] = DotProduct(in1, in2[0]);
out[1] = DotProduct(in1, in2[1]);
out[2] = DotProduct(in1, in2[2]);
}
// rotate by the inverse of the matrix
void VectorIRotate (const vec3_t in1, const float in2[3][4], vec3_t out)
{
out[0] = in1[0]*in2[0][0] + in1[1]*in2[1][0] + in1[2]*in2[2][0];
out[1] = in1[0]*in2[0][1] + in1[1]*in2[1][1] + in1[2]*in2[2][1];
out[2] = in1[0]*in2[0][2] + in1[1]*in2[1][2] + in1[2]*in2[2][2];
}
void VectorTransform (const vec3_t in1, const float in2[3][4], vec3_t out)
{
out[0] = DotProduct(in1, in2[0]) + in2[0][3];
out[1] = DotProduct(in1, in2[1]) + in2[1][3];
out[2] = DotProduct(in1, in2[2]) + in2[2][3];
}
void AngleQuaternion( const vec3_t angles, vec4_t quaternion )
{
float angle;
float sr, sp, sy, cr, cp, cy;
// FIXME: rescale the inputs to 1/2 angle
angle = angles[2] * 0.5;
sy = sin(angle);
cy = cos(angle);
angle = angles[1] * 0.5;
sp = sin(angle);
cp = cos(angle);
angle = angles[0] * 0.5;
sr = sin(angle);
cr = cos(angle);
quaternion[0] = sr*cp*cy-cr*sp*sy; // X
quaternion[1] = cr*sp*cy+sr*cp*sy; // Y
quaternion[2] = cr*cp*sy-sr*sp*cy; // Z
quaternion[3] = cr*cp*cy+sr*sp*sy; // W
}
void QuaternionMatrix( const vec4_t quaternion, float (*matrix)[4] )
{
matrix[0][0] = 1.0 - 2.0 * quaternion[1] * quaternion[1] - 2.0 * quaternion[2] * quaternion[2];
matrix[1][0] = 2.0 * quaternion[0] * quaternion[1] + 2.0 * quaternion[3] * quaternion[2];
matrix[2][0] = 2.0 * quaternion[0] * quaternion[2] - 2.0 * quaternion[3] * quaternion[1];
matrix[0][1] = 2.0 * quaternion[0] * quaternion[1] - 2.0 * quaternion[3] * quaternion[2];
matrix[1][1] = 1.0 - 2.0 * quaternion[0] * quaternion[0] - 2.0 * quaternion[2] * quaternion[2];
matrix[2][1] = 2.0 * quaternion[1] * quaternion[2] + 2.0 * quaternion[3] * quaternion[0];
matrix[0][2] = 2.0 * quaternion[0] * quaternion[2] + 2.0 * quaternion[3] * quaternion[1];
matrix[1][2] = 2.0 * quaternion[1] * quaternion[2] - 2.0 * quaternion[3] * quaternion[0];
matrix[2][2] = 1.0 - 2.0 * quaternion[0] * quaternion[0] - 2.0 * quaternion[1] * quaternion[1];
}
void QuaternionSlerp( const vec4_t p, vec4_t q, float t, vec4_t qt )
{
int i;
float omega, cosom, sinom, sclp, sclq;
// decide if one of the quaternions is backwards
float a = 0;
float b = 0;
for (i = 0; i < 4; i++) {
a += (p[i]-q[i])*(p[i]-q[i]);
b += (p[i]+q[i])*(p[i]+q[i]);
}
if (a > b) {
for (i = 0; i < 4; i++) {
q[i] = -q[i];
}
}
cosom = p[0]*q[0] + p[1]*q[1] + p[2]*q[2] + p[3]*q[3];
if ((1.0 + cosom) > 0.00000001) {
if ((1.0 - cosom) > 0.00000001) {
omega = acos( cosom );
sinom = sin( omega );
sclp = sin( (1.0 - t)*omega) / sinom;
sclq = sin( t*omega ) / sinom;
}
else {
sclp = 1.0 - t;
sclq = t;
}
for (i = 0; i < 4; i++) {
qt[i] = sclp * p[i] + sclq * q[i];
}
}
else {
qt[0] = -p[1];
qt[1] = p[0];
qt[2] = -p[3];
qt[3] = p[2];
sclp = sin( (1.0 - t) * 0.5 * Q_PI);
sclq = sin( t * 0.5 * Q_PI);
for (i = 0; i < 3; i++) {
qt[i] = sclp * p[i] + sclq * qt[i];
}
}
}