ref: 2f67e21393c25943f25e116fa6912b7d92dbca4e
dir: /sys/src/games/doom/tables.h/
// Emacs style mode select -*- C++ -*- //----------------------------------------------------------------------------- // // $Id:$ // // Copyright (C) 1993-1996 by id Software, Inc. // // This source is available for distribution and/or modification // only under the terms of the DOOM Source Code License as // published by id Software. All rights reserved. // // The source is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code 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 "m_fixed.h" #define FINEANGLES 8192 #define FINEMASK (FINEANGLES-1) // 0x100000000 to 0x2000 #define ANGLETOFINESHIFT 19 // Effective size is 10240. extern fixed_t finesine[5*FINEANGLES/4]; // Re-use data, is just PI/2 pahse shift. extern fixed_t* finecosine; // Effective size is 4096. extern 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 angle_t tantoangle[SLOPERANGE+1]; // Utility function, // called by R_PointToAngle. int SlopeDiv ( unsigned num, unsigned den); #endif //----------------------------------------------------------------------------- // // $Log:$ // //-----------------------------------------------------------------------------