quakeforge/include/QF/math/vector.h

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/*
mathlib.h
Vector math library
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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifndef __QF_math_vector_h
#define __QF_math_vector_h
/** \defgroup mathlib_vector Vector functions
\ingroup mathlib
*/
//@{
#include "QF/qtypes.h"
extern const vec_t *const vec3_origin;
#define DotProduct(a,b) ((a)[0] * (b)[0] + (a)[1] * (b)[1] + (a)[2] * (b)[2])
#define VectorSubtract(a,b,c) \
do { \
(c)[0] = (a)[0] - (b)[0]; \
(c)[1] = (a)[1] - (b)[1]; \
(c)[2] = (a)[2] - (b)[2]; \
} while (0)
#define VectorNegate(a,b) \
do { \
(b)[0] = -(a)[0]; \
(b)[1] = -(a)[1]; \
(b)[2] = -(a)[2]; \
} while (0)
#define VectorAdd(a,b,c) \
do { \
(c)[0] = (a)[0] + (b)[0]; \
(c)[1] = (a)[1] + (b)[1]; \
(c)[2] = (a)[2] + (b)[2]; \
} while (0)
#define VectorCopy(a,b) \
do { \
(b)[0] = (a)[0]; \
(b)[1] = (a)[1]; \
(b)[2] = (a)[2]; \
} while (0)
#define VectorMultAdd(a,s,b,c) \
do { \
(c)[0] = (a)[0] + (s) * (b)[0]; \
(c)[1] = (a)[1] + (s) * (b)[1]; \
(c)[2] = (a)[2] + (s) * (b)[2]; \
} while (0)
#define VectorMultSub(a,s,b,c) \
do { \
(c)[0] = (a)[0] - (s) * (b)[0]; \
(c)[1] = (a)[1] - (s) * (b)[1]; \
(c)[2] = (a)[2] - (s) * (b)[2]; \
} while (0)
#define VectorLength(a) sqrt(DotProduct(a, a))
#define VectorScale(a,b,c) \
do { \
(c)[0] = (a)[0] * (b); \
(c)[1] = (a)[1] * (b); \
(c)[2] = (a)[2] * (b); \
} while (0)
/** Shear vector \a b by vector \a a.
Vector a represents the shear factors XY, XZ, YZ, ie in matrix form:
[ 1 0 0 ] [ b0 ]
[ a0 1 0 ] [ b1 ]
[ a1 a2 1 ] [ b2 ]
The reason for this particular scheme is that is how Mat4Decompose
calculates the shear from a matrix.
\note The order of calculations is important for when b and c refer to
the same vector.
*/
#define VectorShear(a,b,c) \
do { \
(c)[2] = (b)[0] * (a)[1] + (b)[1] * (a)[2] + (b)[2]; \
(c)[1] = (b)[0] * (a)[0] + (b)[1]; \
(c)[0] = (b)[0]; \
} while (0)
#define VectorUnshear(a,b,c) \
do { \
(c)[2] = (b)[2] - (b)[1] * (a)[2] - (b)[0] * ((a)[1]-(a)[0]*(a)[2]); \
(c)[1] = (b)[1] - (b)[0] * (a)[0]; \
(c)[0] = (b)[0]; \
} while (0)
#define VectorCompMult(a,b,c) \
do { \
(c)[0] = (a)[0] * (b)[0]; \
(c)[1] = (a)[1] * (b)[1]; \
(c)[2] = (a)[2] * (b)[2]; \
} while (0)
#define VectorCompDiv(a,b,c) \
do { \
(c)[0] = (a)[0] / (b)[0]; \
(c)[1] = (a)[1] / (b)[1]; \
(c)[2] = (a)[2] / (b)[2]; \
} while (0)
#define VectorCompCompare(x, op, y) \
(((x)[0] op (y)[0]) && ((x)[1] op (y)[1]) && ((x)[2] op (y)[2]))
#define VectorCompare(x, y) VectorCompCompare (x, ==, y)
#define VectorCompMin(a, b, c) \
do { \
(c)[0] = min ((a)[0], (b)[0]); \
(c)[1] = min ((a)[1], (b)[1]); \
(c)[2] = min ((a)[2], (b)[2]); \
} while (0)
#define VectorCompMax(a, b, c) \
do { \
(c)[0] = max ((a)[0], (b)[0]); \
(c)[1] = max ((a)[1], (b)[1]); \
(c)[2] = max ((a)[2], (b)[2]); \
} while (0)
#define VectorCompBound(a, b, c, d) \
do { \
(d)[0] = bound ((a)[0], (b)[0], (c)[0]); \
(d)[1] = bound ((a)[1], (b)[1], (c)[1]); \
(d)[2] = bound ((a)[2], (b)[2], (c)[2]); \
} while (0)
#define VectorIsZero(a) (!(a)[0] && !(a)[1] && !(a)[2])
#define VectorZero(a) ((a)[2] = (a)[1] = (a)[0] = 0);
#define VectorSet(a,b,c,d) \
do { \
(d)[0] = a; \
(d)[1] = b; \
(d)[2] = c; \
} while (0)
#define VectorBlend(v1,v2,b,v) \
do { \
(v)[0] = (v1)[0] * (1 - (b)) + (v2)[0] * (b); \
(v)[1] = (v1)[1] * (1 - (b)) + (v2)[1] * (b); \
(v)[2] = (v1)[2] * (1 - (b)) + (v2)[2] * (b); \
} while (0)
//For printf etc
#define VectorExpand(v) (v)[0], (v)[1], (v)[2]
/*
* VectorDistance, the distance between two points.
* Yes, this is the same as sqrt(VectorSubtract then DotProduct),
* however that way would involve more vars, this is cheaper.
*/
#define VectorDistance_fast(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])))
#define VectorDistance(a, b) sqrt(VectorDistance_fast(a, b))
vec_t _DotProduct (const vec3_t v1, const vec3_t v2);
void _VectorAdd (const vec3_t veca, const vec3_t vecb, vec3_t out);
void _VectorCopy (const vec3_t in, vec3_t out);
int _VectorCompare (const vec3_t v1, const vec3_t v2); // uses EQUAL_EPSILON
vec_t _VectorLength (const vec3_t v);
void _VectorMA (const vec3_t veca, float scale, const vec3_t vecb,
vec3_t vecc);
void _VectorScale (const vec3_t in, vec_t scale, vec3_t out);
void _VectorSubtract (const vec3_t veca, const vec3_t vecb, vec3_t out);
void CrossProduct (const vec3_t v1, const vec3_t v2, vec3_t cross);
vec_t _VectorNormalize (vec3_t v); // returns vector length
extern inline float VectorNormalize (vec3_t v); // returns vector length
#ifndef IMPLEMENT_VectorNormalize
extern inline
#else
VISIBLE
#endif
float
VectorNormalize (vec3_t v)
{
float length;
length = DotProduct (v, v);
if (length) {
float ilength;
length = sqrt (length);
ilength = 1.0 / length;
v[0] *= ilength;
v[1] *= ilength;
v[2] *= ilength;
}
return length;
}
//@}
#endif // __QF_math_vector_h