src/Sockets/RandomNumber.cpp

   1 /**
   2  * @author Adam McLaurin
   3  * @date   September 2006
   4  */
   5 /*
   6 This program is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU General Public License
   8 as published by the Free Software Foundation; either version 2
   9 of the License, or (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GN6U General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  19 */
  20 #include "RandomNumber.h"
  21 #include <limits>
  22 #include <time.h>
  23
  24 #ifdef SOCKETS_NAMESPACE
  25 namespace SOCKETS_NAMESPACE {
  26 #endif
  27
  28 const unsigned long int RandomNumber::X_SEED_DEFAULT = 123456789UL;
  29 const unsigned long int RandomNumber::Y_SEED_DEFAULT = 362436069UL;
  30 const unsigned long int RandomNumber::Z_SEED_DEFAULT = 521288629UL;
  31 const unsigned long int RandomNumber::W_SEED_DEFAULT = 88675123UL;
  32
  33
  34 RandomNumber::RandomNumber(bool time_shuffle)
  35 :mXSeed(time_shuffle ? (unsigned long)time(NULL) ^ X_SEED_DEFAULT : X_SEED_DEFAULT)
  36 ,mYSeed(time_shuffle ? (unsigned long)time(NULL) ^ Y_SEED_DEFAULT : Y_SEED_DEFAULT)
  37 ,mZSeed(time_shuffle ? (unsigned long)time(NULL) ^ Z_SEED_DEFAULT : Z_SEED_DEFAULT)
  38 ,mWSeed(time_shuffle ? (unsigned long)time(NULL) ^ W_SEED_DEFAULT : W_SEED_DEFAULT)
  39 {
  40   reset();
  41 }
  42
  43 RandomNumber::RandomNumber(
  44   unsigned long int x_seed,
  45   unsigned long int y_seed,
  46   unsigned long int z_seed,
  47   unsigned long int w_seed)
  48 :mXSeed(x_seed)
  49 ,mYSeed(y_seed)
  50 ,mZSeed(z_seed)
  51 ,mWSeed(w_seed)
  52 {
  53   reset();
  54 }
  55
  56 RandomNumber::~RandomNumber()
  57 {
  58 }
  59
  60 void RandomNumber::reset()
  61 {
  62   mX = mXSeed;
  63   mY = mYSeed;
  64   mZ = mZSeed;
  65   mW = mWSeed;
  66 }
  67
  68 RandomNumber::operator unsigned long int() const
  69 {
  70   return(mW);
  71 }
  72
  73 unsigned long int RandomNumber::next()
  74 {
  75   register unsigned long int t = (mX ^ (mX<<11));
  76
  77   mX = mY;
  78
  79   mY = mZ;
  80
  81   mZ = mW;
  82
  83   return(mW = (mW ^ (mW>>19)) ^ (t ^ (t>>8)));
  84 }
  85
  86 unsigned long int RandomNumber::skip(unsigned long int s)
  87 {
  88   for(register unsigned long int i = 0 ; i < s ; ++i)
  89   {
  90     (void)next();
  91   }
  92
  93   return(mW);
  94 }
  95
  96 void RandomNumber::getSeed(
  97   unsigned long int& x_seed,
  98   unsigned long int& y_seed,
  99   unsigned long int& z_seed,
 100   unsigned long int& w_seed)
 101 {
 102   x_seed = mXSeed;
 103   y_seed = mYSeed;
 104   z_seed = mZSeed;
 105   w_seed = mWSeed;
 106 }
 107
 108 unsigned long int RandomNumber::max_random()
 109 {
 110   return(std::numeric_limits<unsigned long int>::max());
 111 }
 112
 113 #ifdef SOCKETS_NAMESPACE
 114 } // namespace SOCKETS_NAMESPACE {
 115 #endif