ref: 350fb1e60c6761d7171df663035846bacc2b8fde
dir: /src/tables.h/
// // Copyright(C) 1993-1996 Id Software, Inc. // Copyright(C) 1993-2008 Raven Software // Copyright(C) 2005-2014 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. // // 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 "doomtype.h" #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]; // Gamma correction tables. extern const byte gammatable[5][256]; // Binary Angle Measument, BAM. #define ANG45 0x20000000 #define ANG90 0x40000000 #define ANG180 0x80000000 #define ANG270 0xc0000000 #define ANG_MAX 0xffffffff #define ANG1 (ANG45 / 45) #define ANG60 (ANG180 / 3) // Heretic code uses this definition as though it represents one // degree, but it is not! This is actually ~1.40 degrees. #define ANG1_X 0x01000000 #define SLOPERANGE 2048 #define SLOPEBITS 11 #define DBITS (FRACBITS-SLOPEBITS) typedef unsigned int 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 int num, unsigned int den); #endif