apps/plugins/doom/m_random.h

   1 /* Emacs style mode select   -*- C++ -*-
   2  *-----------------------------------------------------------------------------
   3  *
   4  *
   5  *  PrBoom a Doom port merged with LxDoom and LSDLDoom
   6  *  based on BOOM, a modified and improved DOOM engine
   7  *  Copyright (C) 1999 by
   8  *  id Software, Chi Hoang, Lee Killough, Jim Flynn, Rand Phares, Ty Halderman
   9  *  Copyright (C) 1999-2000 by
  10  *  Jess Haas, Nicolas Kalkhof, Colin Phipps, Florian Schulze
  11  *
  12  *  This program is free software; you can redistribute it and/or
  13  *  modify it under the terms of the GNU General Public License
  14  *  as published by the Free Software Foundation; either version 2
  15  *  of the License, or (at your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful,
  18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *  GNU General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License
  23  *  along with this program; if not, write to the Free Software
  24  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  25  *  02111-1307, USA.
  26  *
  27  * DESCRIPTION:
  28  *  Functions to return random numbers.
  29  *
  30  *-----------------------------------------------------------------------------*/
  31
  32
  33 #ifndef __M_RANDOM__
  34 #define __M_RANDOM__
  35
  36 #include "doomtype.h"
  37
  38 // killough 1/19/98: rewritten to use to use a better random number generator
  39 // in the new engine, although the old one is available for compatibility.
  40
  41 // killough 2/16/98:
  42 //
  43 // Make every random number generator local to each control-equivalent block.
  44 // Critical for demo sync. Changing the order of this list breaks all previous
  45 // versions' demos. The random number generators are made local to reduce the
  46 // chances of sync problems. In Doom, if a single random number generator call
  47 // was off, it would mess up all random number generators. This reduces the
  48 // chances of it happening by making each RNG local to a control flow block.
  49 //
  50 // Notes to developers: if you want to reduce your demo sync hassles, follow
  51 // this rule: for each call to P_Random you add, add a new class to the enum
  52 // type below for each block of code which calls P_Random. If two calls to
  53 // P_Random are not in "control-equivalent blocks", i.e. there are any cases
  54 // where one is executed, and the other is not, put them in separate classes.
  55 //
  56 // Keep all current entries in this list the same, and in the order
  57 // indicated by the #'s, because they're critical for preserving demo
  58 // sync. Do not remove entries simply because they become unused later.
  59
  60 typedef enum {
  61    pr_skullfly,                // #1
  62    pr_damage,                  // #2
  63    pr_crush,                   // #3
  64    pr_genlift,                 // #4
  65    pr_killtics,                // #5
  66    pr_damagemobj,              // #6
  67    pr_painchance,              // #7
  68    pr_lights,                  // #8
  69    pr_explode,                 // #9
  70    pr_respawn,                 // #10
  71    pr_lastlook,                // #11
  72    pr_spawnthing,              // #12
  73    pr_spawnpuff,               // #13
  74    pr_spawnblood,              // #14
  75    pr_missile,                 // #15
  76    pr_shadow,                  // #16
  77    pr_plats,                   // #17
  78    pr_punch,                   // #18
  79    pr_punchangle,              // #19
  80    pr_saw,                     // #20
  81    pr_plasma,                  // #21
  82    pr_gunshot,                 // #22
  83    pr_misfire,                 // #23
  84    pr_shotgun,                 // #24
  85    pr_bfg,                     // #25
  86    pr_slimehurt,               // #26
  87    pr_dmspawn,                 // #27
  88    pr_missrange,               // #28
  89    pr_trywalk,                 // #29
  90    pr_newchase,                // #30
  91    pr_newchasedir,             // #31
  92    pr_see,                     // #32
  93    pr_facetarget,              // #33
  94    pr_posattack,               // #34
  95    pr_sposattack,              // #35
  96    pr_cposattack,              // #36
  97    pr_spidrefire,              // #37
  98    pr_troopattack,             // #38
  99    pr_sargattack,              // #39
 100    pr_headattack,              // #40
 101    pr_bruisattack,             // #41
 102    pr_tracer,                  // #42
 103    pr_skelfist,                // #43
 104    pr_scream,                  // #44
 105    pr_brainscream,             // #45
 106    pr_cposrefire,              // #46
 107    pr_brainexp,                // #47
 108    pr_spawnfly,                // #48
 109    pr_misc,                    // #49
 110    pr_all_in_one,              // #50
 111    /* CPhipps - new entries from MBF, mostly unused for now */
 112    pr_opendoor,                // #51
 113    pr_targetsearch,            // #52
 114    pr_friends,                 // #53
 115    pr_threshold,               // #54
 116    pr_skiptarget,              // #55
 117    pr_enemystrafe,             // #56
 118    pr_avoidcrush,              // #57
 119    pr_stayonlift,              // #58
 120    pr_helpfriend,              // #59
 121    pr_dropoff,                 // #60
 122    pr_randomjump,              // #61
 123    pr_defect,                  // #62  // Start new entries -- add new entries below
 124
 125    // End of new entries
 126    NUMPRCLASS               // MUST be last item in list
 127 } pr_class_t;
 128
 129 // The random number generator's state.
 130 typedef struct {
 131    unsigned long seed[NUMPRCLASS];      // Each block's random seed
 132    int rndindex, prndindex;             // For compatibility support
 133 } rng_t;
 134
 135 extern rng_t rng;                      // The rng's state
 136
 137 extern unsigned long rngseed;          // The starting seed (not part of state)
 138
 139 // Returns a number from 0 to 255,
 140 #define M_Random() P_Random(pr_misc)
 141
 142 // As M_Random, but used by the play simulation.
 143 int P_Random(pr_class_t);
 144
 145 // Fix randoms for demos.
 146 void M_ClearRandom(void);
 147
 148 #endif