costmap_queue.hpp

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#ifndef COSTMAP_QUEUE__COSTMAP_QUEUE_HPP_
#define COSTMAP_QUEUE__COSTMAP_QUEUE_HPP_
 
#include <cmath>
#include <vector>
#include <limits>
#include <memory>
#include "nav2_costmap_2d/costmap_2d.hpp"
#include "costmap_queue/map_based_queue.hpp"
 
namespace costmap_queue
{
class CellData
{
public:
  CellData(
    const double d, const unsigned int i, const unsigned int x, const unsigned int y,
    const unsigned int sx, const unsigned int sy)
  : distance_(d), index_(i), x_(x), y_(y), src_x_(sx), src_y_(sy)
  {
  }
 
  CellData()
  : distance_(std::numeric_limits<double>::max()), index_(0), x_(0), y_(0), src_x_(0), src_y_(0)
  {
  }
 
  static unsigned absolute_difference(const unsigned x, const unsigned y)
  {
    return (x > y) ? (x - y) : (y - x);
  }
 
  double distance_;
  unsigned int index_;
  unsigned int x_, y_;
  unsigned int src_x_, src_y_;
};
 
class CostmapQueue : public MapBasedQueue<CellData>
{
public:
  explicit CostmapQueue(nav2_costmap_2d::Costmap2D & costmap, bool manhattan = false);
 
  void reset() override;
 
  void enqueueCell(unsigned int x, unsigned int y);
 
  CellData getNextCell();
 
  virtual bool validCellToQueue(const CellData & /*cell*/) {return true;}
  typedef std::shared_ptr<CostmapQueue> Ptr;
 
protected:
  void enqueueCell(
    unsigned int index, unsigned int cur_x, unsigned int cur_y, unsigned int src_x,
    unsigned int src_y);
 
  void computeCache();
 
  nav2_costmap_2d::Costmap2D & costmap_;
  std::vector<bool> seen_;
  int max_distance_;
  bool manhattan_;
 
protected:
  inline double distanceLookup(
    const unsigned int cur_x, const unsigned int cur_y,
    const unsigned int src_x, const unsigned int src_y)
  {
    unsigned int dx = CellData::absolute_difference(cur_x, src_x);
    unsigned int dy = CellData::absolute_difference(cur_y, src_y);
    return cached_distances_[dx][dy];
  }
  std::vector<std::vector<double>> cached_distances_;
  int cached_max_distance_;
};
}  // namespace costmap_queue
 
#endif  // COSTMAP_QUEUE__COSTMAP_QUEUE_HPP_