1  //
 2  // Copyright(C) 1993-1996 Id Software, Inc.
 3  // Copyright(C) 2005-2014 Simon Howard
 4  //
 5  // This program is free software; you can redistribute it and/or
 6  // modify it under the terms of the GNU General Public License
 7  // as published by the Free Software Foundation; either version 2
 8  // of the License, or (at your option) any later version.
 9  //
10  // This program is distributed in the hope that it will be useful,
11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  // GNU General Public License for more details.
14  //
15  // DESCRIPTION:
16  //	Random number LUT.
17  //
18  
19  #if ORIGCODE
20  #include <time.h>
21  #endif
22  
23  #include "m_random.h"
24  
25  #include "main.h"
26  
27  //
28  // M_Random
29  // Returns a 0-255 number
30  //
31  
32  static const unsigned char rndtable[256] = {
33      0,   8, 109, 220, 222, 241, 149, 107,  75, 248, 254, 140,  16,  66 ,
34      74,  21, 211,  47,  80, 242, 154,  27, 205, 128, 161,  89,  77,  36 ,
35      95, 110,  85,  48, 212, 140, 211, 249,  22,  79, 200,  50,  28, 188 ,
36      52, 140, 202, 120,  68, 145,  62,  70, 184, 190,  91, 197, 152, 224 ,
37      149, 104,  25, 178, 252, 182, 202, 182, 141, 197,   4,  81, 181, 242 ,
38      145,  42,  39, 227, 156, 198, 225, 193, 219,  93, 122, 175, 249,   0 ,
39      175, 143,  70, 239,  46, 246, 163,  53, 163, 109, 168, 135,   2, 235 ,
40      25,  92,  20, 145, 138,  77,  69, 166,  78, 176, 173, 212, 166, 113 ,
41      94, 161,  41,  50, 239,  49, 111, 164,  70,  60,   2,  37, 171,  75 ,
42      136, 156,  11,  56,  42, 146, 138, 229,  73, 146,  77,  61,  98, 196 ,
43      135, 106,  63, 197, 195,  86,  96, 203, 113, 101, 170, 247, 181, 113 ,
44      80, 250, 108,   7, 255, 237, 129, 226,  79, 107, 112, 166, 103, 241 ,
45      24, 223, 239, 120, 198,  58,  60,  82, 128,   3, 184,  66, 143, 224 ,
46      145, 224,  81, 206, 163,  45,  63,  90, 168, 114,  59,  33, 159,  95 ,
47      28, 139, 123,  98, 125, 196,  15,  70, 194, 253,  54,  14, 109, 226 ,
48      71,  17, 161,  93, 186,  87, 244, 138,  20,  52, 123, 251,  26,  36 ,
49      17,  46,  52, 231, 232,  76,  31, 221,  84,  37, 216, 165, 212, 106 ,
50      197, 242,  98,  43,  39, 175, 254, 145, 190,  84, 118, 222, 187, 136 ,
51      120, 163, 236, 249
52  };
53  
54  int	rndindex = 0;
55  int	prndindex = 0;
56  
57  // Which one is deterministic?
58  int P_Random (void)
59  {
60      prndindex = (prndindex+1)&0xff;
61      return rndtable[prndindex];
62  }
63  
64  int M_Random (void)
65  {
66      rndindex = (rndindex+1)&0xff;
67      return rndtable[rndindex];
68  }
69  
70  void M_ClearRandom (void)
71  {
72      prndindex = 0;
73  
74      // Seed the M_Random counter from the system time
75  #if ORIGCODE
76      rndindex = time(NULL) & 0xff;
77  #else
78  	rndindex = systime & 0xff;
79  #endif
80  }