ref: 8e024a47e049234fc0502ad723dc165388f6e795
dir: /src/tables.h/
// Emacs style mode select -*- C++ -*- //----------------------------------------------------------------------------- // // Copyright(C) 1993-1996 Id Software, Inc. // Copyright(C) 2005 Simon Howard // // 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. // // DESCRIPTION: // Lookup tables. // Do not try to look them up :-). // In the order of appearance: // // int finetangent[4096] - Tangens LUT. // Should work with BAM fairly well (12 of 16bit, // effectively, by shifting). // // int finesine[10240] - Sine lookup. // Guess what, serves as cosine, too. // Remarkable thing is, how to use BAMs with this? // // int tantoangle[2049] - ArcTan LUT, // maps tan(angle) to angle fast. Gotta search. // //----------------------------------------------------------------------------- #ifndef __TABLES__ #define __TABLES__ #include "m_fixed.h" #define FINEANGLES 8192 #define FINEMASK (FINEANGLES-1) // 0x100000000 to 0x2000 #define ANGLETOFINESHIFT 19 // Effective size is 10240. extern const fixed_t finesine[5*FINEANGLES/4]; // Re-use data, is just PI/2 pahse shift. extern const fixed_t *finecosine; // Effective size is 4096. extern const fixed_t finetangent[FINEANGLES/2]; // Binary Angle Measument, BAM. #define ANG45 0x20000000 #define ANG90 0x40000000 #define ANG180 0x80000000 #define ANG270 0xc0000000 #define SLOPERANGE 2048 #define SLOPEBITS 11 #define DBITS (FRACBITS-SLOPEBITS) typedef unsigned angle_t; // Effective size is 2049; // The +1 size is to handle the case when x==y // without additional checking. extern const angle_t tantoangle[SLOPERANGE+1]; // Utility function, // called by R_PointToAngle. int SlopeDiv ( unsigned num, unsigned den); #endif