void Map::generate(const unsigned int city_count,
		const unsigned int width,
		const unsigned int height,
		const unsigned int seed)
{
	cities.resize(city_count);
	std::default_random_engine generator(seed);
	std::uniform_int_distribution<unsigned int> width_distribution(0, width);
	std::uniform_int_distribution<unsigned int> height_distribution(0, height);
	std::uniform_int_distribution<unsigned int> city_distribution(0, city_count - 1);

	for (size_t c = 0; c < city_count; c++)
	{
		cities[c].x = width_distribution(generator);
		cities[c].y = height_distribution(generator);
	}

	start = city_distribution(generator);
	end = city_distribution(generator);
	m_adaptor = MapAdaptor(cities);

	city_tree_t city_tree(2, m_adaptor,
			nanoflann::KDTreeSingleIndexAdaptorParams(10));
	city_tree.buildIndex();

	for (size_t c = 0; c < cities.size(); c++)
	{
		// Set index of city and generate connections
		cities[c].index = c; // Do we need this?
		// Consider 5 closest
		std::vector<size_t> ret_index(CITY_SEARCH + 1);
		std::vector<unsigned int>dist_sqr(CITY_SEARCH + 1);

		city_tree.knnSearch(
				&cities[c].x,
				CITY_SEARCH + 1,
				&ret_index[0],
				&dist_sqr[0]);
		for (size_t i = 1; i < ret_index.size(); i++)
		{
			// Do we include you or not?
			// Bernoulli, do your job buddy!
			std::bernoulli_distribution city_test_distribution(CITY_RATIO);
			if (city_test_distribution(generator))
			{
				// Update our information
				cities[c].neighbors.insert(
						std::make_pair(ret_index[i],
							std::sqrt(dist_sqr[i])));
				cities[ret_index[i]].neighbors.insert(
						std::make_pair(c,
							std::sqrt(dist_sqr[i])));
			}
		}
	}
}
void CFruchtermanReingold::GenerateRandomCoordinates() {
       std::default_random_engine generator;
       std::uniform_int_distribution<int> height_distribution(vgc_nodeRadius, vgc_areaHeight - vgc_nodeRadius);
       std::uniform_int_distribution<int> width_distribution(vgc_nodeRadius, vgc_areaWidth - vgc_nodeRadius);

       for(int i =0; i < vgc_nodes_num; ++i) {
              vgc_vertices[i].v_coordinates.setX(width_distribution(generator));
              vgc_vertices[i].v_coordinates.setY(height_distribution(generator));
       }
}
void ObstaclePointCloud::broadcast() {
  if (q_obstacles_.size() < 1) {
    return;
  }

  const auto sim_obstacles = q_obstacles_.front();

  using Cell = std::pair<float, float>;
  std::vector<Cell> all_cells;
  for (const auto& line : sim_obstacles->obstacles) {
    const auto cells = pedsim::LineObstacleToCells(line.start.x, line.start.y,
                                                   line.end.x, line.end.y);
    std::copy(cells.begin(), cells.end(), std::back_inserter(all_cells));
  }

  constexpr int point_density = 100;
  const int num_points = all_cells.size() * point_density;

  std::default_random_engine generator;

  // \todo - Read params from config file.
  std::uniform_int_distribution<int> color_distribution(1, 255);
  std::uniform_real_distribution<float> height_distribution(0, 1);
  std::uniform_real_distribution<float> width_distribution(-0.5, 0.5);

  sensor_msgs::PointCloud pcd_global;
  pcd_global.header.stamp = ros::Time::now();
  pcd_global.header.frame_id = sim_obstacles->header.frame_id;
  pcd_global.points.resize(num_points);
  pcd_global.channels.resize(1);
  pcd_global.channels[0].name = "intensities";
  pcd_global.channels[0].values.resize(num_points);

  sensor_msgs::PointCloud pcd_local;
  pcd_local.header.stamp = ros::Time::now();
  pcd_local.header.frame_id = robot_odom_.header.frame_id;
  pcd_local.points.resize(num_points);
  pcd_local.channels.resize(1);
  pcd_local.channels[0].name = "intensities";
  pcd_local.channels[0].values.resize(num_points);

  // prepare the transform to robot odom frame.
  tf::StampedTransform robot_transform;
  try {
    transform_listener_->lookupTransform(robot_odom_.header.frame_id,
                                         sim_obstacles->header.frame_id,
                                         ros::Time(0), robot_transform);
  } catch (tf::TransformException& e) {
    ROS_WARN_STREAM_THROTTLE(5.0, "TFP lookup from ["
                                      << sim_obstacles->header.frame_id
                                      << "] to [" << robot_odom_.header.frame_id
                                      << "] failed. Reason: " << e.what());
    return;
  }

  size_t index = 0;
  for (const auto& cell : all_cells) {
    const int cell_color = color_distribution(generator);

    for (size_t j = 0; j < point_density; ++j) {
      if (fov_->inside(cell.first, cell.second)) {
        const tf::Vector3 point(cell.first + width_distribution(generator),
                                cell.second + width_distribution(generator),
                                0.);
        const auto transformed_point = transformPoint(robot_transform, point);

        pcd_local.points[index].x = transformed_point.getOrigin().x();
        pcd_local.points[index].y = transformed_point.getOrigin().y();
        pcd_local.points[index].z = height_distribution(generator);
        pcd_local.channels[0].values[index] = cell_color;

        // Global observations.
        pcd_global.points[index].x = cell.first + width_distribution(generator);
        pcd_global.points[index].y =
            cell.second + width_distribution(generator);
        pcd_global.points[index].z = height_distribution(generator);
        pcd_global.channels[0].values[index] = cell_color;
      }

      index++;
    }
  }

  if (pcd_local.channels[0].values.size() > 1) {
    pub_signals_local_.publish(pcd_local);
  }
  if (pcd_global.channels[0].values.size() > 1) {
    pub_signals_global_.publish(pcd_global);
  }

  q_obstacles_.pop();
};