i6eRandom.h

Go to the documentation of this file.

/*
 * i6engine
 * Copyright (2016) Daniel Bonrath, Michael Baer, All rights reserved.
 *
 * This file is part of i6engine; i6engine 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
 */

#ifndef __I6ENGINE_UTILS_RANDOM_H__
#define __I6ENGINE_UTILS_RANDOM_H__

#include <mutex>
#include <random>

#include "i6engine/utils/Exceptions.h"
#include "i6engine/utils/Singleton.h"

#include "boost/date_time.hpp"

namespace i6e {
namespace utils {

        class ISIXE_UTILS_API Random : public Singleton<Random> {
                friend class Singleton<Random>;

        public:
                ~Random() {
                        delete _linear;
                }

                uint32_t rand() const {
                        return getRand();
                }

                uint32_t rand(uint32_t max) const {
                        if (max == 0) {
                                ISIXE_THROW_API("i6eRandom", "max value has to be grater than zero")
                        }
                        return getRand() % max;
                }

                uint32_t rand(uint32_t min, uint32_t max) const {
                        if (min >= max) {
                                ISIXE_THROW_API("i6eRandom", "max value has to be greater than min value")
                        }
                        return (getRand() % (max - min)) + min;
                }

                void setSeed(uint32_t seed) {
                        std::lock_guard<std::mutex> l(_lock);
                        _linear->seed(seed);
                }

        private:
                std::minstd_rand * _linear;

                mutable std::mutex _lock;

                uint32_t getRand() const {
                        std::lock_guard<std::mutex> l(_lock);
                        return (*_linear)();
                }

                Random() : _linear(new std::minstd_rand(static_cast<unsigned int>(boost::posix_time::time_period(boost::posix_time::time_from_string("2010-03-19 14:23:10"), boost::posix_time::microsec_clock::universal_time()).length().total_microseconds()))), _lock() {
                }
        };

} /* namespace utils */
} /* namespace i6e */

#endif /* __I6ENGINE_UTILS_RANDOM_H__ */