newtree/source/mathlib.c
2000-12-30 02:16:36 +00:00

643 lines
13 KiB
C

/*
mathlib.c
math primitives
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
$Id$
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif
#include <math.h>
#include "mathlib.h"
#include "model.h"
#include "qtypes.h"
#include "sys.h"
vec3_t vec3_origin = { 0, 0, 0 };
int nanmask = 255 << 23;
/*-----------------------------------------------------------------*/
#define DEG2RAD( a ) ( a * M_PI ) / 180.0F
void
ProjectPointOnPlane (vec3_t dst, const vec3_t p, const vec3_t normal)
{
float d;
vec3_t n;
float inv_denom;
inv_denom = 1.0F / DotProduct (normal, normal);
d = DotProduct (normal, p) * inv_denom;
n[0] = normal[0] * inv_denom;
n[1] = normal[1] * inv_denom;
n[2] = normal[2] * inv_denom;
dst[0] = p[0] - d * n[0];
dst[1] = p[1] - d * n[1];
dst[2] = p[2] - d * n[2];
}
/*
** assumes "src" is normalized
*/
void
PerpendicularVector (vec3_t dst, const vec3_t src)
{
int pos;
int i;
float minelem = 1.0F;
vec3_t tempvec;
/*
** find the smallest magnitude axially aligned vector */
for (pos = 0, i = 0; i < 3; i++) {
if (fabs (src[i]) < minelem) {
pos = i;
minelem = fabs (src[i]);
}
}
tempvec[0] = tempvec[1] = tempvec[2] = 0.0F;
tempvec[pos] = 1.0F;
/*
** project the point onto the plane defined by src */
ProjectPointOnPlane (dst, tempvec, src);
/*
** normalize the result */
VectorNormalize (dst);
}
#if defined(_WIN32) && !defined(__GNUC__)
#pragma optimize( "", off )
#endif
void
RotatePointAroundVector (vec3_t dst, const vec3_t dir, const vec3_t point,
float degrees)
{
float m[3][3];
float im[3][3];
float zrot[3][3];
float tmpmat[3][3];
float rot[3][3];
int i;
vec3_t vr, vup, vf;
vf[0] = dir[0];
vf[1] = dir[1];
vf[2] = dir[2];
PerpendicularVector (vr, dir);
CrossProduct (vr, vf, vup);
m[0][0] = vr[0];
m[1][0] = vr[1];
m[2][0] = vr[2];
m[0][1] = vup[0];
m[1][1] = vup[1];
m[2][1] = vup[2];
m[0][2] = vf[0];
m[1][2] = vf[1];
m[2][2] = vf[2];
memcpy (im, m, sizeof (im));
im[0][1] = m[1][0];
im[0][2] = m[2][0];
im[1][0] = m[0][1];
im[1][2] = m[2][1];
im[2][0] = m[0][2];
im[2][1] = m[1][2];
memset (zrot, 0, sizeof (zrot));
zrot[0][0] = zrot[1][1] = zrot[2][2] = 1.0F;
zrot[0][0] = cos (DEG2RAD (degrees));
zrot[0][1] = sin (DEG2RAD (degrees));
zrot[1][0] = -sin (DEG2RAD (degrees));
zrot[1][1] = cos (DEG2RAD (degrees));
R_ConcatRotations (m, zrot, tmpmat);
R_ConcatRotations (tmpmat, im, rot);
for (i = 0; i < 3; i++) {
dst[i] =
rot[i][0] * point[0] + rot[i][1] * point[1] + rot[i][2] * point[2];
}
}
#if defined(_WIN32) && !defined(__GNUC__)
#pragma optimize( "", on )
#endif
/*-----------------------------------------------------------------*/
float
anglemod (float a)
{
#if 0
if (a >= 0)
a -= 360 * (int) (a / 360);
else
a += 360 * (1 + (int) (-a / 360));
#endif
a = (360.0 / 65536) * ((int) (a * (65536 / 360.0)) & 65535);
return a;
}
/*
==================
BOPS_Error
Split out like this for ASM to call.
==================
*/
void
BOPS_Error (void)
{
Sys_Error ("BoxOnPlaneSide: Bad signbits");
}
#ifndef USE_INTEL_ASM
/*
==================
BoxOnPlaneSide
Returns 1, 2, or 1 + 2
==================
*/
int
BoxOnPlaneSide (vec3_t emins, vec3_t emaxs, mplane_t *p)
{
float dist1, dist2;
int sides;
#if 0 // this is done by the
// BOX_ON_PLANE_SIDE macro before
// calling this
// function
// fast axial cases
if (p->type < 3) {
if (p->dist <= emins[p->type])
return 1;
if (p->dist >= emaxs[p->type])
return 2;
return 3;
}
#endif
// general case
switch (p->signbits) {
case 0:
dist1 =
p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emaxs[2];
dist2 =
p->normal[0] * emins[0] + p->normal[1] * emins[1] +
p->normal[2] * emins[2];
break;
case 1:
dist1 =
p->normal[0] * emins[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emaxs[2];
dist2 =
p->normal[0] * emaxs[0] + p->normal[1] * emins[1] +
p->normal[2] * emins[2];
break;
case 2:
dist1 =
p->normal[0] * emaxs[0] + p->normal[1] * emins[1] +
p->normal[2] * emaxs[2];
dist2 =
p->normal[0] * emins[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emins[2];
break;
case 3:
dist1 =
p->normal[0] * emins[0] + p->normal[1] * emins[1] +
p->normal[2] * emaxs[2];
dist2 =
p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emins[2];
break;
case 4:
dist1 =
p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emins[2];
dist2 =
p->normal[0] * emins[0] + p->normal[1] * emins[1] +
p->normal[2] * emaxs[2];
break;
case 5:
dist1 =
p->normal[0] * emins[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emins[2];
dist2 =
p->normal[0] * emaxs[0] + p->normal[1] * emins[1] +
p->normal[2] * emaxs[2];
break;
case 6:
dist1 =
p->normal[0] * emaxs[0] + p->normal[1] * emins[1] +
p->normal[2] * emins[2];
dist2 =
p->normal[0] * emins[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emaxs[2];
break;
case 7:
dist1 =
p->normal[0] * emins[0] + p->normal[1] * emins[1] +
p->normal[2] * emins[2];
dist2 =
p->normal[0] * emaxs[0] + p->normal[1] * emaxs[1] +
p->normal[2] * emaxs[2];
break;
default:
dist1 = dist2 = 0; // shut up compiler
BOPS_Error ();
break;
}
#if 0
int i;
vec3_t corners[2];
for (i = 0; i < 3; i++) {
if (plane->normal[i] < 0) {
corners[0][i] = emins[i];
corners[1][i] = emaxs[i];
} else {
corners[1][i] = emins[i];
corners[0][i] = emaxs[i];
}
}
dist = DotProduct (plane->normal, corners[0]) - plane->dist;
dist2 = DotProduct (plane->normal, corners[1]) - plane->dist;
sides = 0;
if (dist1 >= 0)
sides = 1;
if (dist2 < 0)
sides |= 2;
#endif
sides = 0;
if (dist1 >= p->dist)
sides = 1;
if (dist2 < p->dist)
sides |= 2;
#ifdef PARANOID
if (sides == 0)
Sys_Error ("BoxOnPlaneSide: sides==0");
#endif
return sides;
}
#endif
void
AngleVectors (vec3_t angles, vec3_t forward, vec3_t right, vec3_t up)
{
float angle;
float sr, sp, sy, cr, cp, cy;
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);
forward[0] = cp * cy;
forward[1] = cp * sy;
forward[2] = -sp;
right[0] = (-1 * sr * sp * cy + -1 * cr * -sy);
right[1] = (-1 * sr * sp * sy + -1 * cr * cy);
right[2] = -1 * sr * cp;
up[0] = (cr * sp * cy + -sr * -sy);
up[1] = (cr * sp * sy + -sr * cy);
up[2] = cr * cp;
}
int
VectorCompare (vec3_t v1, vec3_t v2)
{
int i;
for (i = 0; i < 3; i++)
if (v1[i] != v2[i])
return 0;
return 1;
}
void
VectorMA (vec3_t veca, float scale, vec3_t vecb, vec3_t vecc)
{
vecc[0] = veca[0] + scale * vecb[0];
vecc[1] = veca[1] + scale * vecb[1];
vecc[2] = veca[2] + scale * vecb[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 veca, vec3_t vecb, vec3_t out)
{
out[0] = veca[0] - vecb[0];
out[1] = veca[1] - vecb[1];
out[2] = veca[2] - vecb[2];
}
void
_VectorAdd (vec3_t veca, vec3_t vecb, vec3_t out)
{
out[0] = veca[0] + vecb[0];
out[1] = veca[1] + vecb[1];
out[2] = veca[2] + vecb[2];
}
void
_VectorCopy (vec3_t in, vec3_t out)
{
out[0] = in[0];
out[1] = in[1];
out[2] = in[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];
}
double sqrt (double x);
vec_t
Length (vec3_t v)
{
int i;
float length;
length = 0;
for (i = 0; i < 3; i++)
length += v[i] * v[i];
length = sqrt (length); // FIXME
return length;
}
float
VectorNormalize (vec3_t v)
{
float length, ilength;
length = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
length = sqrt (length); // FIXME
if (length) {
ilength = 1 / length;
v[0] *= ilength;
v[1] *= ilength;
v[2] *= ilength;
}
return length;
}
void
VectorInverse (vec3_t v)
{
v[0] = -v[0];
v[1] = -v[1];
v[2] = -v[2];
}
void
VectorScale (vec3_t in, vec_t scale, vec3_t out)
{
out[0] = in[0] * scale;
out[1] = in[1] * scale;
out[2] = in[2] * scale;
}
int
Q_log2 (int val)
{
int answer = 0;
while ((val >>= 1) != 0)
answer++;
return answer;
}
/*
================
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];
}
/*
================
R_ConcatTransforms
================
*/
void
R_ConcatTransforms (float in1[3][4], 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];
}
/*
===================
FloorDivMod
Returns mathematically correct (floor-based) quotient and remainder for
numer and denom, both of which should contain no fractional part. The
quotient must fit in 32 bits.
====================
*/
void
FloorDivMod (double numer, double denom, int *quotient, int *rem)
{
int q, r;
double x;
#ifndef PARANOID
if (denom <= 0.0)
Sys_Error ("FloorDivMod: bad denominator %f\n", denom);
// if ((floor(numer) != numer) || (floor(denom) != denom))
// Sys_Error ("FloorDivMod: non-integer numer or denom %f %f\n",
// numer, denom);
#endif
if (numer >= 0.0) {
x = floor (numer / denom);
q = (int) x;
r = (int) floor (numer - (x * denom));
} else {
//
// perform operations with positive values, and fix mod to make
// floor-based
//
x = floor (-numer / denom);
q = -(int) x;
r = (int) floor (-numer - (x * denom));
if (r != 0) {
q--;
r = (int) denom - r;
}
}
*quotient = q;
*rem = r;
}
/*
===================
GreatestCommonDivisor
====================
*/
int
GreatestCommonDivisor (int i1, int i2)
{
if (i1 > i2) {
if (i2 == 0)
return (i1);
return GreatestCommonDivisor (i2, i1 % i2);
} else {
if (i1 == 0)
return (i2);
return GreatestCommonDivisor (i1, i2 % i1);
}
}
#ifndef USE_INTEL_ASM
// TODO: move to nonintel.c
/*
===================
Invert24To16
Inverts an 8.24 value to a 16.16 value
====================
*/
fixed16_t
Invert24To16 (fixed16_t val)
{
if (val < 256)
return (0xFFFFFFFF);
return (fixed16_t)
(((double) 0x10000 * (double) 0x1000000 / (double) val) + 0.5);
}
#endif