random_numbers.cpp

Go to the documentation of this file.

/*********************************************************************
 * Software License Agreement (BSD License)
 *
 *  Copyright (c) 2008, Willow Garage, Inc.
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of the Willow Garage nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *********************************************************************/

/* Author: Ioan Sucan */

#include "random_numbers/random_numbers.h"

#include <boost/random/lagged_fibonacci.hpp>
#include <boost/random/uniform_int.hpp>
#include <boost/thread/mutex.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>
#include <boost/math/constants/constants.hpp>
#include <boost/scoped_ptr.hpp>

static boost::uint32_t first_seed_ = 0;

static boost::uint32_t firstSeed(void)
{
  boost::scoped_ptr<int> mem(new int());
  first_seed_ = (boost::uint32_t)(
      (boost::posix_time::microsec_clock::universal_time() - boost::posix_time::ptime(boost::date_time::min_date_time))
          .total_microseconds() +
      (unsigned long long)(mem.get()));
  return first_seed_;
}

static boost::uint32_t nextSeed(void)
{
  static boost::mutex rngMutex;
  boost::mutex::scoped_lock slock(rngMutex);
  static boost::lagged_fibonacci607 sGen(firstSeed());
  static boost::uniform_int<> sDist(1, 1000000000);
  static boost::variate_generator<boost::lagged_fibonacci607&, boost::uniform_int<> > s(sGen, sDist);
  boost::uint32_t v = s();
  return v;
}

random_numbers::RandomNumberGenerator::RandomNumberGenerator(void)
  : generator_(nextSeed())
  , uniDist_(0, 1)
  , normalDist_(0, 1)
  , uni_(generator_, uniDist_)
  , normal_(generator_, normalDist_)
{
}

random_numbers::RandomNumberGenerator::RandomNumberGenerator(boost::uint32_t seed)
  : generator_(seed), uniDist_(0, 1), normalDist_(0, 1), uni_(generator_, uniDist_), normal_(generator_, normalDist_)
{
  // Because we manually specified a seed, we need to save it ourselves
  first_seed_ = seed;
}

// From: "Uniform Random Rotations", Ken Shoemake, Graphics Gems III,
//       pg. 124-132
void random_numbers::RandomNumberGenerator::quaternion(double value[4])
{
  double x0 = uni_();
  double r1 = sqrt(1.0 - x0), r2 = sqrt(x0);
  double t1 = 2.0 * boost::math::constants::pi<double>() * uni_(),
         t2 = 2.0 * boost::math::constants::pi<double>() * uni_();
  double c1 = cos(t1), s1 = sin(t1);
  double c2 = cos(t2), s2 = sin(t2);
  value[0] = s1 * r1;
  value[1] = c1 * r1;
  value[2] = s2 * r2;
  value[3] = c2 * r2;
}

boost::uint32_t random_numbers::RandomNumberGenerator::getFirstSeed()
{
  return first_seed_;
}