random.cpp

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#include "utils/random.hpp"

#include <ctime>



Random Random::m_RandomGenerator;


Random::Random()
    : m_RandomSeed(0)
{
    m_RandomSeed = (unsigned int)clock();

    if(m_RandomSeed == 0)
        m_RandomSeed = 1;

    next();
}

Random::Random(unsigned long _init)
    : m_RandomSeed(_init)
{
}

Random::~Random()
{
}


void Random::next()
{
    // optimized standard minimal
    long tmp0 = 16807L * (m_RandomSeed & 0xFFFFL);
    long tmp1 = 16807L * (m_RandomSeed >> 16);
    long tmp2 = (tmp0 >> 16) + tmp1;
         tmp0 = ((tmp0 & 0xFFFF)|((tmp2 & 0x7FFF) << 16)) + (tmp2 >> 15);

    // correction of the error
    if ((tmp0 & 0x80000000L) != 0)
        tmp0 = (tmp0 + 1) & 0x7FFFFFFFL;

    m_RandomSeed = tmp0;
}