LightningDB.h

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/* Author: Dave Coleman
   Desc:   Implementation of the Lightning Framework for experienced-based planning

   Paper:  Berenson, Dmitry, Pieter Abbeel, and Ken Goldberg.
           "A robot path planning framework that learns from experience."
           Robotics and Automation (ICRA), 2012 IEEE International Conference on. IEEE, 2012.
*/

#ifndef OMPL_TOOLS_LIGHTNING_LIGHTNINGDB_
#define OMPL_TOOLS_LIGHTNING_LIGHTNINGDB_

#include "ompl/base/StateSpace.h"
#include "ompl/geometric/PathGeometric.h"
#include "ompl/base/PlannerData.h"
#include "ompl/base/PlannerDataStorage.h"
#include "ompl/base/State.h"
#include "ompl/base/SpaceInformation.h"
#include "ompl/datastructures/NearestNeighbors.h"

namespace ompl
{

    namespace tools
    {
        OMPL_CLASS_FORWARD(LightningDB);

        class LightningDB
        {
        public:

            LightningDB(const base::StateSpacePtr &space);

            virtual ~LightningDB();

            bool load(const std::string &fileName);

            void addPath(geometric::PathGeometric &solutionPath, double &insertionTime);
            void addPathHelper(geometric::PathGeometric &solutionPath);

            bool saveIfChanged(const std::string &fileName);

            bool save(const std::string &fileName);

            void getAllPlannerDatas(std::vector<ompl::base::PlannerDataPtr> &plannerDatas) const;

            std::vector<ompl::base::PlannerDataPtr> findNearestStartGoal(int nearestK,
                const base::State *start, const base::State *goal);

            std::size_t getExperiencesCount() const;

            std::size_t getStatesCount() const;

            int getNumUnsavedPaths() const
            {
                return numUnsavedPaths_;
            }

            bool isEmpty()
            {
                return getExperiencesCount() == 0;
            }

        private:

            double distanceFunction(const ompl::base::PlannerDataPtr a, const ompl::base::PlannerDataPtr b) const;

        protected:

            base::SpaceInformationPtr si_;

            ompl::base::PlannerDataStorage plannerDataStorage_;

            // A nearest-neighbors datastructure containing the tree of start/goal states combined
            std::shared_ptr< NearestNeighbors<ompl::base::PlannerDataPtr> > nn_;

            // Reusable plannerData instance for filling in start and goal and performing searches on the tree
            ompl::base::PlannerDataPtr nnSearchKey_;

            // Track unsaved paths to determine if a save is required
            int numUnsavedPaths_;

        }; // end of class LightningDB

    } // end of namespace

} // end of namespace
#endif