gtkradiant/tools/quake2/common/mathlib.c

/*
   Copyright (C) 1999-2007 id Software, Inc. and contributors.
   For a list of contributors, see the accompanying CONTRIBUTORS file.

   This file is part of GtkRadiant.

   GtkRadiant 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.

   GtkRadiant 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 GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
// mathlib.c -- math primitives

#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;
}

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 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 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( 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;
		}
	}
}