source: GTP/trunk/Lib/Vis/Preprocessing/src/Halton.cpp @ 2105

#include "Halton.h"
#include "PerfTimer.h"

#define PREGENERATE_HALTON 0

namespace GtpVisibilityPreprocessor {

PerfTimer haltonTimer;

// global halton generator

  Halton2 halton2;
  float Halton2::_invBases[2];

  float Halton<1>::_invBases[1];
  float Halton<2>::_invBases[2];
  float Halton<3>::_invBases[3];
  float Halton<4>::_invBases[4];
  float Halton<5>::_invBases[5];
  float Halton<6>::_invBases[6];
  

  Halton<1> dummmyHalton1(true);
  Halton<2> dummmyHalton2(true);
  Halton<3> dummmyHalton3(true);
  Halton<4> dummmyHalton4(true);
  Halton<5> dummmyHalton5(true);
  Halton<6> dummmyHalton6(true);


  int HaltonSequence::sPregeneratedDim = 0;
  int HaltonSequence::sPregeneratedNumber = 0;
  float *HaltonSequence::sPregeneratedValues = NULL;
  
#if PREGENERATE_HALTON
  // pregenerate first 100k numbers for 6 dimensions
  static HaltonSequence staticHalton(6, 200000);
#endif
  
  // special construtor for pregenerating static halton sequences
  HaltonSequence::HaltonSequence(const int dim,
                                                                 const int number) {

        sPregeneratedDim = 0;
        sPregeneratedNumber = 0;
        sPregeneratedValues = new float[number*dim];

        float *p = sPregeneratedValues;
        int i;
        for (i=0; i < number; i++, p+=dim) {
          GetNext(dim, p);
        }
        
        sPregeneratedDim = dim;
        sPregeneratedNumber = number;
  }

void
HaltonSequence::GetNext(const int dimensions, float *p)
{
  //  haltonTimer.Entry();
#if PREGENERATE_HALTON
  if (index <= sPregeneratedNumber && dimensions <= sPregeneratedDim) {
        float *pp = sPregeneratedValues + (sPregeneratedDim*(index-1));
        for (int i=0; i < dimensions; i++)
          p[i] = pp[i];
  } else
#endif
        {
          for (int i=0; i < dimensions; i++)
                p[i] = (float)GetNumber(i+1);
        }
  GenerateNext();
  //  haltonTimer.Exit();
}

}