astar.h

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#ifndef DLUX_PLUGINS_ASTAR_H
#define DLUX_PLUGINS_ASTAR_H

#include <dlux_global_planner/potential_calculator.h>
#include <queue>
#include <vector>

namespace dlux_plugins
{

class AStar : public dlux_global_planner::PotentialCalculator
{
public:
  // Main PotentialCalculator interface
  void initialize(ros::NodeHandle& private_nh, nav_core2::Costmap::Ptr costmap,
                  dlux_global_planner::CostInterpreter::Ptr cost_interpreter) override;
  unsigned int updatePotentials(dlux_global_planner::PotentialGrid& potential_grid,
                                const geometry_msgs::Pose2D& start, const geometry_msgs::Pose2D& goal) override;
protected:
  void add(dlux_global_planner::PotentialGrid& potential_grid, double prev_potential,
           const nav_grid::Index& index, const nav_grid::Index& start_index);

  float getHeuristicValue(const nav_grid::Index& index, const nav_grid::Index& start_index) const;

  struct QueueEntry
  {
  public:
    QueueEntry(nav_grid::Index index, float heuristic) : i(index), cost(heuristic) {}
    nav_grid::Index i;
    float cost;
  };

  struct QueueEntryComparator
  {
    bool operator()(const QueueEntry& a, const QueueEntry& b) const
    {
      return a.cost > b.cost;
    }
  };

  // Indexes sorted by heuristic
  using AStarQueue = std::priority_queue<QueueEntry, std::vector<QueueEntry>, QueueEntryComparator>;
  AStarQueue queue_;
  bool manhattan_heuristic_;
  bool use_kernel_;
  double minimum_requeue_change_;
};
}  // namespace dlux_plugins

#endif  // DLUX_PLUGINS_ASTAR_H