mirror of
https://github.com/ZDoom/raze-gles.git
synced 2024-12-27 04:00:42 +00:00
112 lines
2.5 KiB
C
112 lines
2.5 KiB
C
/*
|
|
* mathutil.c
|
|
* Mathematical utility functions to emulate MACT
|
|
*
|
|
* by Jonathon Fowler
|
|
*
|
|
* Since we weren't given the source for MACT386.LIB so I've had to do some
|
|
* creative interpolation here.
|
|
*
|
|
*/
|
|
//-------------------------------------------------------------------------
|
|
/*
|
|
Duke Nukem Copyright (C) 1996, 2003 3D Realms Entertainment
|
|
|
|
This file is part of Duke Nukem 3D version 1.5 - Atomic Edition
|
|
|
|
Duke Nukem 3D 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.
|
|
*/
|
|
//-------------------------------------------------------------------------
|
|
|
|
#include "types.h"
|
|
|
|
#if 0
|
|
// Ken's reverse-engineering job
|
|
int32 FindDistance2D(int32 x, int32 y)
|
|
{
|
|
int32 i;
|
|
x = labs(x);
|
|
y = labs(y);
|
|
if (!x) return(y);
|
|
if (!y) return(x);
|
|
if (y < x) { i = x; x = y; y = i; } //swap x, y
|
|
x += (x>>1);
|
|
return ((x>>6)+(x>>2)+y-(y>>5)-(y>>7)); //handle 1 octant
|
|
}
|
|
|
|
// My abomination
|
|
#define square(x) ((x)*(x))
|
|
/*
|
|
int32 FindDistance2D(int32 dx, int32 dy)
|
|
{
|
|
// return (int32)floor(sqrt((double)(sqr(dx)+sqr(dy))));
|
|
return ksqrt(square(dx)+square(dy));
|
|
}
|
|
*/
|
|
int32 FindDistance3D(int32 dx, int32 dy, int32 dz)
|
|
{
|
|
// return (int32)floor(sqrt((double)(sqr(dx)+sqr(dy)+sqr(dz))));
|
|
return ksqrt(square(dx)+square(dy)+square(dz));
|
|
}
|
|
|
|
#else
|
|
|
|
#include <stdlib.h>
|
|
|
|
// This extracted from the Rise of the Triad source RT_UTIL.C :-|
|
|
|
|
#define SWAP(a,b) \
|
|
{ \
|
|
a=(a)^(b); \
|
|
b=(a)^(b); \
|
|
a=(a)^(b); \
|
|
}
|
|
|
|
int32 FindDistance2D(int32 x, int32 y)
|
|
{
|
|
int32 t;
|
|
|
|
x= abs(x); /* absolute values */
|
|
y= abs(y);
|
|
|
|
if (x<y)
|
|
SWAP(x,y);
|
|
|
|
t = y + (y>>1);
|
|
|
|
return (x - (x>>5) - (x>>7) + (t>>2) + (t>>6));
|
|
}
|
|
|
|
|
|
int32 FindDistance3D(int32 x, int32 y, int32 z)
|
|
{
|
|
int32 t;
|
|
|
|
x= abs(x); /* absolute values */
|
|
y= abs(y);
|
|
z= abs(z);
|
|
|
|
if (x<y)
|
|
SWAP(x,y);
|
|
|
|
if (x<z)
|
|
SWAP(x,z);
|
|
|
|
t = y + z;
|
|
|
|
return (x - (x>>4) + (t>>2) + (t>>3));
|
|
}
|
|
#endif
|