/******************************************************** * Some code. Copyright (C) 2003 by Pascal Massimino.   * * All Rights Reserved.      (http://skal.planet-d.net) * * For Educational/Academic use ONLY. See 'LICENSE.TXT'.* ********************************************************//* * skl_randomize.cpp * * Rand utilities ***********************************************/#include "skl.h"#include "skl_syst/skl_random.h"#include <math.h>//////////////////////////////////////////////////////////// SKL_RANDOM//////////////////////////////////////////////////////////#define UPPER_MASK 0x80000000#define LOWER_MASK 0x7fffffff  // Tempering parameters#define TEMPERING_MASK_B 0x9d2c5680#define TEMPERING_MASK_C 0xefc60000#define TEMPERING_SHIFT_U(y)  (y >> 11)#define TEMPERING_SHIFT_S(y)  (y << 7)#define TEMPERING_SHIFT_T(y)  (y << 15)#define TEMPERING_SHIFT_L(y)  (y >> 18)void SKL_RANDOM::Set_Seed(SKL_UINT32 s){    // generator used: Line 25 of Table 1 in    // [KNUTH 1981, The Art of Computer Programming    //    Vol. 2 (2nd Ed.), pp102]  for (_n=N; _n>0; _n--) {    _V[_n-1] = s;    s = (69069 * s) & 0xffffffff;  }}void SKL_RANDOM::Freshen(){  static const SKL_UINT32 M01[] = {0x0, 0x9908b0df};    // constant vector A  SKL_UINT32 *V = (SKL_UINT32*)_V;  SKL_INT32 kk;  for ( kk=0; kk<N-M; kk++)  {    SKL_UINT32 y = ( V[kk] & UPPER_MASK ) | ( V[kk+1] & LOWER_MASK );    V[kk] = V[kk+M] ^ (y >> 1) ^ M01[y & 0x1];  }  for ( ; kk<N-1; kk++)  {    SKL_UINT32 y = ( V[kk] & UPPER_MASK ) | ( V[kk+1] & LOWER_MASK );    V[kk] = V[kk+(M-N)] ^ (y >> 1) ^ M01[y & 0x1];  }  SKL_UINT32 y = ( V[N-1] & UPPER_MASK ) | ( V[0] & LOWER_MASK );  V[N-1] = V[M-1] ^ (y >> 1) ^ M01[y & 0x1];  _n = N;}SKL_UINT32 SKL_RANDOM::Get(){  if (Is_Used_Up()) Freshen();  SKL_UINT32 y = _V[--_n];  y ^= TEMPERING_SHIFT_U(y);  y ^= TEMPERING_SHIFT_S(y) & TEMPERING_MASK_B;  y ^= TEMPERING_SHIFT_T(y) & TEMPERING_MASK_C;  y ^= TEMPERING_SHIFT_L(y);  return y;}float SKL_RANDOM::Gauss(float Amp){  float x = 1.0f - Get_Float();  SKL_ASSERT(x>.0 && x<=1.0f);  x = (float)( Amp*sqrt(-log(x)) );  return ( Get()&0x01 ) ? -x : x;}//////////////////////////////////////////////////////////