AOXRRTConnect.h

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/* Author: Tyler Wilson */
 
#ifndef OMPL_GEOMETRIC_PLANNERS_RRT_AOX_RRT_CONNECT_
#define OMPL_GEOMETRIC_PLANNERS_RRT_AOX_RRT_CONNECT_
 
#include "ompl/datastructures/NearestNeighbors.h"
#include "ompl/base/OptimizationObjective.h"
#include "ompl/geometric/planners/PlannerIncludes.h"
#include <ompl/geometric/planners/rrt/RRTConnect.h>
 
#include "ompl/base/Path.h"
 
namespace ompl
{
    namespace geometric
    {

        class AOXRRTConnect : public base::Planner
        {
        public:
            AOXRRTConnect(const base::SpaceInformationPtr &si);
 
            ~AOXRRTConnect() override;
 
            base::PlannerStatus solve(const base::PlannerTerminationCondition &ptc) override;
 
            void setFoundPath(const base::PathPtr &p)
            {
                foundPath = p;
            }
 
            base::PathPtr getFoundPath() const
            {
                return foundPath;
            }

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

            double getRange() const
            {
                return maxDistance_;
            }

            template <template <typename T> class NN>
            void setNearestNeighbors()
            {
                if ((tStart_ && tStart_->size() != 0) || (tGoal_ && tGoal_->size() != 0))
                    OMPL_WARN("Calling setNearestNeighbors will clear all states.");
                clear();
                tStart_ = std::make_shared<NN<Motion *>>();
                tGoal_ = std::make_shared<NN<Motion *>>();
                setup();
            }

            bool internalResetCondition()
            {
                bool shouldReset = false;
                if (tStart_ && tGoal_)
                {
                    /* Reset if we have met our maximum internal vertices */
                    shouldReset = shouldReset || (tStart_->size() + tGoal_->size() >= maxInternalVertices);
                }
                else
                {
                    /* If our trees don't exist, we're not in the middle of a search anyways */
                    shouldReset = true;
                }
                /* Reset if we have attempted our maximum internal samples */
                shouldReset = shouldReset || (sampleAttempts >= maxInternalSamples);
                return shouldReset;
            }
 
            void setup() override;
 
            void reset(bool solvedProblem);
 
            void setPathCost(double pc);
 
        protected:
            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};
                double cost{0};
                bool connecting{false};
            };

            using TreeData = std::shared_ptr<NearestNeighbors<Motion *>>;

            struct TreeGrowingInfo
            {
                base::State *xstate;
                Motion *xmotion;
                bool start;
            };

            enum GrowState
            {
                /* no progress has been made */
                TRAPPED,
                /* progress has been made towards the randomly sampled state */
                ADVANCED,
                /* the randomly sampled state was reached */
                REACHED
            };

            void freeMemory();

            double euclideanDistanceFunction(const Motion *a, const Motion *b) const
            {
                return si_->distance(a->state, b->state);
            }

            double aoxDistanceFunction(const Motion *a, const Motion *b) const
            {
                auto space_diff = si_->distance(a->state, b->state);
                auto cost_diff = a->cost - b->cost;
 
                auto dist = sqrt(pow(space_diff, 2) + pow(cost_diff, 2));
 
                return dist;
            }

            Motion *findNeighbour(Motion *sampled_motion, float rootDist, TreeData &tree);

            GrowState growTree(TreeData &tree, TreeGrowingInfo &tgi, Motion *rmotion);

            base::InformedSamplerPtr sampler_;
 
            std::size_t sampleAttempts{0};
 
            /* Pad rootDist to account for floating point error
               Needed to make sure the root is included in nearest list
               TODO: Should use some relative epsilon for padding
               (FLT_EPSILON is good but does not scale with the magnitude of rootDist and may be too small) */
            const float rootDistPadding = 0.00001;

            TreeData tStart_;

            TreeData tGoal_;

            bool startTree_{true};

            double maxDistance_{0.};

            long int maxResampleAttempts_{100};

            std::size_t maxInternalVertices{10000};

            std::size_t maxInternalVerticesIncrement{10000};

            std::size_t maxInternalSamples{10000000};

            std::size_t maxInternalSamplesIncrement{10000000};
 
            base::State *startState{nullptr};
            base::State *goalState{nullptr};

            base::Cost bestCost_{std::numeric_limits<double>::infinity()};

            base::PathPtr foundPath{nullptr};

            base::PlannerTerminationCondition _ptc{nullptr};

            base::OptimizationObjectivePtr opt_;

            RNG rng_;

            std::pair<base::State *, base::State *> connectionPoint_;
        };
    }  // namespace geometric
}  // namespace ompl
 
#endif