ew-engine/mq engine src/mathlib.c
2006-10-08 00:00:00 +00:00

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6.7 KiB
C

/*
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.c -- math primitives
// Tomaz - Whole File Redone
#include <math.h>
#include "quakedef.h"
void Sys_Error (char *error, ...);
vec3_t vec3_origin = {0,0,0};
int nanmask = 255<<23;
/*-----------------------------------------------------------------*/
double angleModScalar1;
double angleModScalar2;
float degRadScalar;
void Math_Init()
{
degRadScalar = (float)(M_PI / 180.0);
angleModScalar1 = (360.0 / 65536.0);
angleModScalar2 = (65536.0 / 360.0);
}
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 );
}
#ifdef _WIN32
#pragma optimize( "", off )
#endif
void VectorVectors(const vec3_t forward, vec3_t right, vec3_t up)
{
float d;
right[0] = forward[2];
right[1] = -forward[0];
right[2] = forward[1];
d = -DotProduct(forward, right);
VectorMA (right, d, forward, right);
VectorNormalize(right);
CrossProduct(right, forward, up);
}
void RotatePointAroundVector( vec3_t dst, const vec3_t dir, const vec3_t point, float degrees )
{
float t0, t1;
float angle, c, s;
vec3_t vr, vu, vf;
angle = DEG2RAD(degrees);
c = cos(angle);
s = sin(angle);
VectorCopy (dir, vf);
VectorVectors(vf, vr, vu);
t0 = vr[0] * c + vu[0] * -s;
t1 = vr[0] * s + vu[0] * c;
dst[0] = (t0 * vr[0] + t1 * vu[0] + vf[0] * vf[0]) * point[0]
+ (t0 * vr[1] + t1 * vu[1] + vf[0] * vf[1]) * point[1]
+ (t0 * vr[2] + t1 * vu[2] + vf[0] * vf[2]) * point[2];
t0 = vr[1] * c + vu[1] * -s;
t1 = vr[1] * s + vu[1] * c;
dst[1] = (t0 * vr[0] + t1 * vu[0] + vf[1] * vf[0]) * point[0]
+ (t0 * vr[1] + t1 * vu[1] + vf[1] * vf[1]) * point[1]
+ (t0 * vr[2] + t1 * vu[2] + vf[1] * vf[2]) * point[2];
t0 = vr[2] * c + vu[2] * -s;
t1 = vr[2] * s + vu[2] * c;
dst[2] = (t0 * vr[0] + t1 * vu[0] + vf[2] * vf[0]) * point[0]
+ (t0 * vr[1] + t1 * vu[1] + vf[2] * vf[1]) * point[1]
+ (t0 * vr[2] + t1 * vu[2] + vf[2] * vf[2]) * point[2];
}
#ifdef _WIN32
#pragma optimize( "", on )
#endif
/*-----------------------------------------------------------------*/
float anglemod(float a)
{
a = angleModScalar1 * ((int)(a * angleModScalar2) & 65535); // Tomaz Speed
return a;
}
/*
==================
BoxOnPlaneSide
Returns 1, 2, or 1 + 2
==================
*/
int BoxOnPlaneSide (vec3_t emins, vec3_t emaxs, mplane_t *p)
{
float dist1, dist2;
int sides;
// 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
Sys_Error ("BoxOnPlaneSide: Bad signbits");
break;
}
sides = 0;
if (dist1 >= p->dist)
sides = 1;
if (dist2 < p->dist)
sides |= 2;
return sides;
}
void AngleVectors (vec3_t angles, vec3_t forward, vec3_t right, vec3_t up)
{
float angle;
float sr, sp, sy, cr, cp, cy;
angle = DEG2RAD(angles[YAW]); // Tomaz Speed
sy = sin(angle);
cy = cos(angle);
angle = DEG2RAD(angles[PITCH]); // Tomaz Speed
sp = sin(angle);
cp = cos(angle);
if (right || up)
{
angle = DEG2RAD(angles[ROLL]); // Tomaz Speed
sr = sin(angle);
cr = cos(angle);
}
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;
}
}
float VectorNormalize (vec3_t v)
{
float length = v[0]*v[0] + v[1]*v[1] + v[2]*v[2];
if (length)
{
float ilength;
length = sqrt (length); // FIXME
ilength = 1/length;
v[0] *= ilength;
v[1] *= ilength;
v[2] *= ilength;
}
return length;
}