/* * 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 #include "compat.h" #include "pragmas.h" // I wonder if it's faster to use Ken's functions here... int32_t FindDistance2D(int32_t x, int32_t y) { if ((x=klabs(x)) < (y=klabs(y))) swaplong(&x,&y); { int32_t t = y + (y>>1); return (x - (x>>5) - (x>>7) + (t>>2) + (t>>6)); } } int32_t FindDistance3D(int32_t x, int32_t y, int32_t z) { if ((x=klabs(x)) < (y=klabs(y))) swaplong(&x,&y); if (x < (z=klabs(z))) swaplong(&x,&z); { int32_t t = y + z; return (x - (x>>4) + (t>>2) + (t>>3)); } }