inflation_layer.hpp

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 * Author: Eitan Marder-Eppstein
 *         David V. Lu!!
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#ifndef NAV2_COSTMAP_2D__INFLATION_LAYER_HPP_
#define NAV2_COSTMAP_2D__INFLATION_LAYER_HPP_
 
#include <map>
#include <vector>
#include <mutex>
#include <memory>
#include <string>
 
#include "rclcpp/rclcpp.hpp"
#include "nav2_costmap_2d/layer.hpp"
#include "nav2_costmap_2d/layered_costmap.hpp"
#include "nav2_costmap_2d/costmap_2d_ros.hpp"
 
namespace nav2_costmap_2d
{
class CellData
{
public:
  CellData(unsigned int x, unsigned int y, unsigned int sx, unsigned int sy)
  : x_(x), y_(y), src_x_(sx), src_y_(sy)
  {
  }
  unsigned int x_, y_;
  unsigned int src_x_, src_y_;
};
 
class InflationLayer : public Layer
{
public:
  InflationLayer();
 
  ~InflationLayer();
 
  void onInitialize() override;
 
  void updateBounds(
    double robot_x, double robot_y, double robot_yaw, double * min_x,
    double * min_y,
    double * max_x,
    double * max_y) override;
  void updateCosts(
    nav2_costmap_2d::Costmap2D & master_grid,
    int min_i, int min_j, int max_i, int max_j) override;
 
  void matchSize() override;
 
  bool isClearable() override {return false;}
 
  void reset() override
  {
    matchSize();
    current_ = false;
    need_reinflation_ = true;
  }
 
  inline unsigned char computeCost(double distance) const
  {
    unsigned char cost = 0;
    if (distance == 0) {
      cost = LETHAL_OBSTACLE;
    } else if (distance * resolution_ <= inscribed_radius_) {
      cost = INSCRIBED_INFLATED_OBSTACLE;
    } else {
      // make sure cost falls off by Euclidean distance
      double factor =
        exp(-1.0 * cost_scaling_factor_ * (distance * resolution_ - inscribed_radius_));
      cost = static_cast<unsigned char>((INSCRIBED_INFLATED_OBSTACLE - 1) * factor);
    }
    return cost;
  }
 
  static std::shared_ptr<nav2_costmap_2d::InflationLayer> getInflationLayer(
    std::shared_ptr<nav2_costmap_2d::Costmap2DROS> & costmap_ros,
    const std::string layer_name = "")
  {
    const auto layered_costmap = costmap_ros->getLayeredCostmap();
    for (auto layer = layered_costmap->getPlugins()->begin();
      layer != layered_costmap->getPlugins()->end();
      ++layer)
    {
      auto inflation_layer = std::dynamic_pointer_cast<nav2_costmap_2d::InflationLayer>(*layer);
      if (inflation_layer) {
        if (layer_name.empty() || inflation_layer->getName() == layer_name) {
          return inflation_layer;
        }
      }
    }
    return nullptr;
  }
 
  // Provide a typedef to ease future code maintenance
  typedef std::recursive_mutex mutex_t;
 
  mutex_t * getMutex()
  {
    return access_;
  }
 
  double getCostScalingFactor()
  {
    return cost_scaling_factor_;
  }
 
  double getInflationRadius()
  {
    return inflation_radius_;
  }
 
protected:
  void onFootprintChanged() override;
 
  inline double distanceLookup(
    unsigned int mx, unsigned int my, unsigned int src_x,
    unsigned int src_y)
  {
    unsigned int dx = (mx > src_x) ? mx - src_x : src_x - mx;
    unsigned int dy = (my > src_y) ? my - src_y : src_y - my;
    return cached_distances_[dx * cache_length_ + dy];
  }
 
  inline unsigned char costLookup(
    unsigned int mx, unsigned int my, unsigned int src_x,
    unsigned int src_y)
  {
    unsigned int dx = (mx > src_x) ? mx - src_x : src_x - mx;
    unsigned int dy = (my > src_y) ? my - src_y : src_y - my;
    return cached_costs_[dx * cache_length_ + dy];
  }
 
  void computeCaches();
 
  int generateIntegerDistances();
 
  unsigned int cellDistance(double world_dist)
  {
    return layered_costmap_->getCostmap()->cellDistance(world_dist);
  }
 
  inline void enqueue(
    unsigned int index, unsigned int mx, unsigned int my,
    unsigned int src_x, unsigned int src_y);
 
  rcl_interfaces::msg::SetParametersResult
  dynamicParametersCallback(std::vector<rclcpp::Parameter> parameters);
 
  double inflation_radius_, inscribed_radius_, cost_scaling_factor_;
  bool inflate_unknown_, inflate_around_unknown_;
  unsigned int cell_inflation_radius_;
  unsigned int cached_cell_inflation_radius_;
  std::vector<std::vector<CellData>> inflation_cells_;
 
  double resolution_;
 
  std::vector<bool> seen_;
 
  std::vector<unsigned char> cached_costs_;
  std::vector<double> cached_distances_;
  std::vector<std::vector<int>> distance_matrix_;
  unsigned int cache_length_;
  double last_min_x_, last_min_y_, last_max_x_, last_max_y_;
 
  // Indicates that the entire costmap should be reinflated next time around.
  bool need_reinflation_;
  mutex_t * access_;
  // Dynamic parameters handler
  rclcpp::node_interfaces::OnSetParametersCallbackHandle::SharedPtr dyn_params_handler_;
};
 
}  // namespace nav2_costmap_2d
 
#endif  // NAV2_COSTMAP_2D__INFLATION_LAYER_HPP_