random.cpp

//------------------------------------------------------------------------------
// random.cpp
//------------------------------------------------------------------------------
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
// 02110-1301  USA
//
//------------------------------------------------------------------------------
// Copyright (C) 2010 "Zalewa" <zalewapl@gmail.com>
//------------------------------------------------------------------------------
#include "random.h"

#include <QDateTime>

QSharedPointer<std::mt19937> Random::generator = QSharedPointer<std::mt19937>();

void Random::builtInInit()
{
        if (Random::generator.isNull())
        {
                std::random_device randomDevice;
                init(randomDevice() + QDateTime::currentDateTime().toMSecsSinceEpoch());
        }
}

void Random::init(int seed)
{
        Random::generator.reset(new std::mt19937(seed));
}

unsigned short Random::nextUShort(unsigned short max)
{
        builtInInit();
        return (*Random::generator.data())() % max;
}