l_math.c

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code 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 2 of the License,
or (at your option) any later version.

Quake III Arena source code 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 Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/
// mathlib.c -- math primitives

#include "l_cmd.h"
#include "l_math.h"

vec3_t vec3_origin = {0,0,0};

void AngleVectors (const vec3_t angles, vec3_t forward, vec3_t right, vec3_t up)
{
	float		angle;
	static float		sr, sp, sy, cr, cp, cy;
	// static to help MS compiler fp bugs

	angle = angles[YAW] * (M_PI*2 / 360);
	sy = sin(angle);
	cy = cos(angle);
	angle = angles[PITCH] * (M_PI*2 / 360);
	sp = sin(angle);
	cp = cos(angle);
	angle = angles[ROLL] * (M_PI*2 / 360);
	sr = sin(angle);
	cr = cos(angle);

	if (forward)
	{
		forward[0] = cp*cy;
		forward[1] = cp*sy;
		forward[2] = -sp;
	}
	if (right)
	{
		right[0] = (-1*sr*sp*cy+-1*cr*-sy);
		right[1] = (-1*sr*sp*sy+-1*cr*cy);
		right[2] = -1*sr*cp;
	}
	if (up)
	{
		up[0] = (cr*sp*cy+-sr*-sy);
		up[1] = (cr*sp*sy+-sr*cy);
		up[2] = cr*cp;
	}
}

/*
=================
RadiusFromBounds
=================
*/
float RadiusFromBounds( const vec3_t mins, const vec3_t maxs ) {
	int		i;
	vec3_t	corner;
	float	a, b;

	for (i=0 ; i<3 ; i++) {
		a = fabs( mins[i] );
		b = fabs( maxs[i] );
		corner[i] = a > b ? a : b;
	}

	return VectorLength (corner);
}

/*
================
R_ConcatRotations
================
*/
void R_ConcatRotations (float in1[3][3], float in2[3][3], float out[3][3])
{
	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[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[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];
}

void AxisClear( vec3_t axis[3] ) {
	axis[0][0] = 1;
	axis[0][1] = 0;
	axis[0][2] = 0;
	axis[1][0] = 0;
	axis[1][1] = 1;
	axis[1][2] = 0;
	axis[2][0] = 0;
	axis[2][1] = 0;
	axis[2][2] = 1;
}

float VectorLengthSquared(vec3_t v) {
	return DotProduct(v, v);
}

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;
}

qboolean 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 CrossProduct (const vec3_t v1, const 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];
}

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];
}

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 inout)
{
	vec_t	length, ilength;

	length = sqrt (inout[0]*inout[0] + inout[1]*inout[1] + inout[2]*inout[2]);
	if (length == 0)
	{
		VectorClear (inout);
		return 0;
	}

	ilength = 1.0/length;
	inout[0] = inout[0]*ilength;
	inout[1] = inout[1]*ilength;
	inout[2] = inout[2]*ilength;

	return length;
}

vec_t VectorNormalize2(const vec3_t in, vec3_t out)
{
	vec_t	length, ilength;

	length = sqrt (in[0]*in[0] + in[1]*in[1] + in[2]*in[2]);
	if (length == 0)
	{
		VectorClear (out);
		return 0;
	}

	ilength = 1.0/length;
	out[0] = in[0]*ilength;
	out[1] = in[1]*ilength;
	out[2] = in[2]*ilength;

	return length;
}

vec_t ColorNormalize (vec3_t in, vec3_t out)
{
	float	max, scale;

	max = in[0];
	if (in[1] > max)
		max = in[1];
	if (in[2] > max)
		max = in[2];

	if (max == 0)
		return 0;

	scale = 1.0 / max;

	VectorScale (in, scale, out);

	return max;
}



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(const 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;
	}
}