glquake/source/mathlib.h

/*
Copyright (C) 1996-1997 Id Software, Inc.

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 2
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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// mathlib.h

typedef float vec_t;
typedef vec_t vec3_t[3];
typedef vec_t vec5_t[5];
typedef vec_t vec2_t[2];

typedef	int	fixed4_t;
typedef	int	fixed8_t;
typedef	int	fixed16_t;

#ifndef M_PI
#define M_PI		3.14159265358979323846	// matches value in gcc v2 math.h
#endif

struct mplane_s;

extern vec3_t vec3_origin;
extern	int nanmask;

#define	IS_NAN(x) (((*(int *)&x)&nanmask)==nanmask)

#define Q_rint(x) ((x) > 0 ? (int)((x) + 0.5) : (int)((x) - 0.5)) //johnfitz -- from joequake

#define DotProduct(x,y) (x[0]*y[0]+x[1]*y[1]+x[2]*y[2])
#define DoublePrecisionDotProduct(x,y) ((double)x[0]*y[0]+(double)x[1]*y[1]+(double)x[2]*y[2])
#define VectorLerp( v1, lerp, v2, c ) ((c)[0] = (v1)[0] + (lerp) * ((v2)[0] - (v1)[0]), (c)[1] = (v1)[1] + (lerp) * ((v2)[1] - (v1)[1]), (c)[2] = (v1)[2] + (lerp) * ((v2)[2] - (v1)[2]))
#define VectorSubtract(a,b,c) {c[0]=a[0]-b[0];c[1]=a[1]-b[1];c[2]=a[2]-b[2];}
#define VectorAdd(a,b,c) {c[0]=a[0]+b[0];c[1]=a[1]+b[1];c[2]=a[2]+b[2];}
#define VectorCopy(a,b) {b[0]=a[0];b[1]=a[1];b[2]=a[2];}
#define VectorClear(a)		((a)[0] = (a)[1] = (a)[2] = 0)
#define VectorSet(v, x, y, z)	((v)[0] = (x), (v)[1] = (y), (v)[2] = (z))
#define VectorNegate(a, b)	((b)[0] = -(a)[0], (b)[1] = -(a)[1], (b)[2] = -(a)[2])
#define VectorMax(a,b,out) {out[0]=a[0]>b[0]?a[0]:b[0]; out[1]=a[1]>b[1]?a[1]:b[1]; out[2]=a[2]>b[2]?a[2]:b[2];}
#define VectorMin(a,b,out) {out[0]=a[0]<b[0]?a[0]:b[0]; out[1]=a[1]<b[1]?a[1]:b[1]; out[2]=a[2]<b[2]?a[2]:b[2];}
#define DEG2RAD( a ) ( a * M_PI ) / 180.0F

#define VectorNormalizeFast( v ){float	ilength = (float)rsqrt(DotProduct(v,v));v[0] *= ilength;v[1] *= ilength;v[2] *= ilength; }
#define VectorDistanceSquared(a,b)((a[0]-b[0])*(a[0]-b[0])+(a[1]-b[1])*(a[1]-b[1])+(a[2]-b[2])*(a[2]-b[2]))

void VectorMA (vec3_t veca, float scale, vec3_t vecb, vec3_t vecc);

vec_t _DotProduct (vec3_t v1, vec3_t v2);
void _VectorSubtract (vec3_t veca, vec3_t vecb, vec3_t out);
void _VectorAdd (vec3_t veca, vec3_t vecb, vec3_t out);
void _VectorCopy (vec3_t in, vec3_t out);

void vectoangles (vec3_t vec, vec3_t ang);

#define VectorInterpolate(v1, _frac, v2, v)		\
do {											\
	_mathlib_temp_float1 = _frac;				\
												\
	(v)[0] = (v1)[0] + _mathlib_temp_float1 * ((v2)[0] - (v1)[0]);\
	(v)[1] = (v1)[1] + _mathlib_temp_float1 * ((v2)[1] - (v1)[1]);\
	(v)[2] = (v1)[2] + _mathlib_temp_float1 * ((v2)[2] - (v1)[2]);\
} while(0)

int VectorCompare (vec3_t v1, vec3_t v2);
#define Length(v) (sqrtf(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]))
void CrossProduct (vec3_t v1, vec3_t v2, vec3_t cross);
float VectorLength (vec3_t v);
float VecLength2(vec3_t v1, vec3_t v2);
float VectorNormalize (vec3_t v);		// returns vector length
void VectorInverse (vec3_t v);
void VectorScale (vec3_t in, vec_t scale, vec3_t out);
int Q_log2(int val);

void R_ConcatRotations (float in1[3][3], float in2[3][3], float out[3][3]);
void R_ConcatTransforms (float in1[3][4], float in2[3][4], float out[3][4]);

void FloorDivMod (double numer, double denom, int *quotient,
		int *rem);
fixed16_t Invert24To16(fixed16_t val);
int GreatestCommonDivisor (int i1, int i2);

void AngleVectors (vec3_t angles, vec3_t forward, vec3_t right, vec3_t up);
int BoxOnPlaneSide (vec3_t emins, vec3_t emaxs, struct mplane_s *plane);
float	anglemod(float a);

extern int _mathlib_temp_int1, _mathlib_temp_int2, _mathlib_temp_int3;
extern float _mathlib_temp_float1, _mathlib_temp_float2, _mathlib_temp_float3;
extern vec3_t _mathlib_temp_vec1, _mathlib_temp_vec2, _mathlib_temp_vec3;

#define VectorL2Compare(v, w, m)					\
	(_mathlib_temp_float1 = (m) * (m),				\
	_mathlib_temp_vec1[0] = (v)[0] - (w)[0], _mathlib_temp_vec1[1] = (v)[1] - (w)[1], _mathlib_temp_vec1[2] = (v)[2] - (w)[2],\
	_mathlib_temp_vec1[0] * _mathlib_temp_vec1[0] +	\
	_mathlib_temp_vec1[1] * _mathlib_temp_vec1[1] +	\
	_mathlib_temp_vec1[2] * _mathlib_temp_vec1[2] < _mathlib_temp_float1)

#define VectorSupCompare(v, w, m)								\
	(_mathlib_temp_float1 = m,									\
	(v)[0] - (w)[0] > -_mathlib_temp_float1 && (v)[0] - (w)[0] < _mathlib_temp_float1 &&	\
	(v)[1] - (w)[1] > -_mathlib_temp_float1 && (v)[1] - (w)[1] < _mathlib_temp_float1 &&	\
	(v)[2] - (w)[2] > -_mathlib_temp_float1 && (v)[2] - (w)[2] < _mathlib_temp_float1)

#define BOX_ON_PLANE_SIDE(emins, emaxs, p)	\
	(((p)->type < 3)?						\
	(										\
		((p)->dist <= (emins)[(p)->type])?	\
			1								\
		:									\
		(									\
			((p)->dist >= (emaxs)[(p)->type])?\
				2							\
			:								\
				3							\
		)									\
	)										\
	:										\
		BoxOnPlaneSide( (emins), (emaxs), (p)))


float rsqrt( float number );