pSBL.h

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/* Author: Ioan Sucan */

#ifndef OMPL_GEOMETRIC_PLANNERS_SBL_pSBL_
#define OMPL_GEOMETRIC_PLANNERS_SBL_pSBL_

#include "ompl/geometric/planners/PlannerIncludes.h"
#include "ompl/base/ProjectionEvaluator.h"
#include "ompl/base/StateSamplerArray.h"
#include "ompl/datastructures/Grid.h"
#include "ompl/datastructures/PDF.h"
#include <thread>
#include <mutex>
#include <vector>

namespace ompl
{
    namespace geometric
    {
        class pSBL : public base::Planner
        {
        public:
            pSBL(const base::SpaceInformationPtr &si);

            ~pSBL() override;

            void setProjectionEvaluator(const base::ProjectionEvaluatorPtr &projectionEvaluator)
            {
                projectionEvaluator_ = projectionEvaluator;
            }

            void setProjectionEvaluator(const std::string &name)
            {
                projectionEvaluator_ = si_->getStateSpace()->getProjection(name);
            }

            const base::ProjectionEvaluatorPtr &getProjectionEvaluator() const
            {
                return projectionEvaluator_;
            }

            void setRange(double distance)
            {
                maxDistance_ = distance;
            }

            double getRange() const
            {
                return maxDistance_;
            }

            void setThreadCount(unsigned int nthreads);

            unsigned int getThreadCount() const
            {
                return threadCount_;
            }

            void setup() override;

            base::PlannerStatus solve(const base::PlannerTerminationCondition &ptc) override;

            void clear() override;

            void getPlannerData(base::PlannerData &data) const override;

        protected:
            class Motion;
            struct MotionInfo;

            typedef Grid<MotionInfo>::Cell GridCell;

            typedef PDF<GridCell *> CellPDF;

            class Motion
            {
            public:
                Motion() = default;

                Motion(const base::SpaceInformationPtr &si)
                  : state(si->allocState())
                {
                }

                ~Motion() = default;

                const base::State *root{nullptr};
                base::State *state{nullptr};
                Motion *parent{nullptr};
                bool valid{false};
                std::vector<Motion *> children;
                std::mutex lock;
            };

            struct MotionInfo
            {
                Motion *operator[](unsigned int i)
                {
                    return motions_[i];
                }
                std::vector<Motion *>::iterator begin()
                {
                    return motions_.begin();
                }
                void erase(std::vector<Motion *>::iterator iter)
                {
                    motions_.erase(iter);
                }
                void push_back(Motion *m)
                {
                    motions_.push_back(m);
                }
                unsigned int size() const
                {
                    return motions_.size();
                }
                bool empty() const
                {
                    return motions_.empty();
                }
                std::vector<Motion *> motions_;
                CellPDF::Element *elem_;
            };

            struct TreeData
            {
                TreeData() = default;

                Grid<MotionInfo> grid{0};
                unsigned int size{0};
                CellPDF pdf;
                std::mutex lock;
            };

            struct SolutionInfo
            {
                std::vector<Motion *> solution;
                bool found;
                std::mutex lock;
            };

            struct PendingRemoveMotion
            {
                TreeData *tree;
                Motion *motion;
            };

            struct MotionsToBeRemoved
            {
                std::vector<PendingRemoveMotion> motions;
                std::mutex lock;
            };

            void threadSolve(unsigned int tid, const base::PlannerTerminationCondition &ptc, SolutionInfo *sol);

            void freeMemory()
            {
                freeGridMotions(tStart_.grid);
                freeGridMotions(tGoal_.grid);
            }

            void freeGridMotions(Grid<MotionInfo> &grid);

            void addMotion(TreeData &tree, Motion *motion);
            Motion *selectMotion(RNG &rng, TreeData &tree);
            void removeMotion(TreeData &tree, Motion *motion, std::map<Motion *, bool> &seen);
            bool isPathValid(TreeData &tree, Motion *motion);
            bool checkSolution(RNG &rng, bool start, TreeData &tree, TreeData &otherTree, Motion *motion,
                               std::vector<Motion *> &solution);

            base::StateSamplerArray<base::ValidStateSampler> samplerArray_;
            base::ProjectionEvaluatorPtr projectionEvaluator_;

            TreeData tStart_;
            TreeData tGoal_;

            MotionsToBeRemoved removeList_;
            std::mutex loopLock_;
            std::mutex loopLockCounter_;
            unsigned int loopCounter_;

            double maxDistance_{0.};

            unsigned int threadCount_;

            std::pair<base::State *, base::State *> connectionPoint_{nullptr, nullptr};
        };
    }
}

#endif