ReverseQueue.h

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// Authors: Marlin Strub
 
#ifndef OMPL_GEOMETRIC_PLANNERS_INFORMEDTREES_EITSTAR_REVERSE_QUEUE_
#define OMPL_GEOMETRIC_PLANNERS_INFORMEDTREES_EITSTAR_REVERSE_QUEUE_
 
#include <array>
#include <map>
#include <tuple>
 
#include "ompl/base/Cost.h"
#include "ompl/base/samplers/InformedStateSampler.h"
#include "ompl/datastructures/BinaryHeap.h"
#include "ompl/datastructures/NearestNeighbors.h"
 
#include "ompl/geometric/planners/informedtrees/eitstar/Direction.h"
#include "ompl/geometric/planners/informedtrees/eitstar/Edge.h"
#include "ompl/geometric/planners/informedtrees/eitstar/Vertex.h"
 
namespace ompl
{
    namespace geometric
    {
        namespace eitstar
        {
            class ReverseQueue
            {
            public:
                ReverseQueue(const std::shared_ptr<const ompl::base::OptimizationObjective> &objective,
                             const std::shared_ptr<const ompl::base::StateSpace> &space, const bool isQueueCostOrdered);

                ~ReverseQueue() = default;

                bool empty() const;

                std::size_t size() const;

                void insertOrUpdate(const Edge &edge);

                void insertOrUpdate(const std::vector<Edge> &edges);

                const Edge &peek() const;

                unsigned int peekEffort() const;

                Edge pop();

                void setCostQueueOrder(const bool isQueueCostOrdered);

                ompl::base::Cost getLowerBoundOnOptimalSolutionCost() const;

                void clear();

                std::vector<Edge> getEdges() const;

                void rebuild();

                void removeOutgoingEdges(const std::shared_ptr<Vertex> &vertex);

                unsigned int computeAdmissibleSolutionEffort(const Edge &edge) const;

                ompl::base::Cost computeAdmissibleSolutionCost(const Edge &edge) const;
 
            private:
                using HeapElement = std::tuple<ompl::base::Cost, ompl::base::Cost, unsigned int, unsigned int, Edge>;
                using CostEffortHeap =
                    ompl::BinaryHeap<HeapElement, std::function<bool(const HeapElement &, const HeapElement &)>>;

                bool updateIfExists(const Edge &edge);

                ompl::base::Cost computeAdmissibleCostToComeToTarget(const Edge &edge) const;

                unsigned int computeInadmissibleSolutionEffort(const Edge &edge) const;

                std::function<bool(const HeapElement &, const HeapElement &)> getCostComparisonOperator() const;

                std::function<bool(const HeapElement &, const HeapElement &)> getEffortComparisonOperator() const;

                bool isQueueCostOrdered_;

                std::shared_ptr<const ompl::base::OptimizationObjective> objective_;

                std::shared_ptr<const ompl::base::StateSpace> space_;

                CostEffortHeap queue_;
            };
        }  // namespace eitstar
 
    }  // namespace geometric
 
}  // namespace ompl
 
#endif  // OMPL_GEOMETRIC_PLANNERS_INFORMEDTREES_EITSTAR_REVERSE_QUEUE_