OptimizationObjective.h

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/* Author: Luis G. Torres, Ioan Sucan, Jonathan Gammell */
 
#ifndef OMPL_BASE_OPTIMIZATION_OBJECTIVE_
#define OMPL_BASE_OPTIMIZATION_OBJECTIVE_
 
#include "ompl/base/Cost.h"
#include "ompl/base/SpaceInformation.h"
#include "ompl/util/ClassForward.h"
#include "ompl/base/ProblemDefinition.h"
#include "ompl/base/samplers/InformedStateSampler.h"
#include "ompl/control/Control.h"
 
#include <functional>
#include <iostream>
 
namespace ompl
{
    namespace base
    {
        class Goal;

        using CostToGoHeuristic = std::function<Cost(const State *, const Goal *)>;


        OMPL_CLASS_FORWARD(OptimizationObjective);


        class OptimizationObjective
        {
        public:
            // non-copyable
            OptimizationObjective(const OptimizationObjective &) = delete;
            OptimizationObjective &operator=(const OptimizationObjective &) = delete;

            OptimizationObjective(SpaceInformationPtr si);
 
            virtual ~OptimizationObjective() = default;

            const std::string &getDescription() const;

            virtual bool isSatisfied(Cost c) const;

            Cost getCostThreshold() const;

            void setCostThreshold(Cost c);

            virtual bool isCostBetterThan(Cost c1, Cost c2) const;

            virtual bool isCostEquivalentTo(Cost c1, Cost c2) const;

            virtual bool isFinite(Cost cost) const;

            virtual Cost betterCost(Cost c1, Cost c2) const;

            virtual Cost stateCost(const State *s) const = 0;

            virtual Cost motionCost(const State *s1, const State *s2) const = 0;

            virtual Cost controlCost(const control::Control *c, unsigned int steps) const;

            virtual Cost combineCosts(Cost c1, Cost c2) const;

            virtual Cost subtractCosts(Cost c1, Cost c2) const;

            virtual Cost identityCost() const;

            virtual Cost infiniteCost() const;

            virtual Cost initialCost(const State *s) const;

            virtual Cost terminalCost(const State *s) const;

            virtual bool isSymmetric() const;

            virtual Cost averageStateCost(unsigned int numStates) const;

            void setCostToGoHeuristic(const CostToGoHeuristic &costToGo);

            bool hasCostToGoHeuristic() const;

            Cost costToGo(const State *state, const Goal *goal) const;

            virtual Cost motionCostHeuristic(const State *s1, const State *s2) const;

            virtual Cost motionCostBestEstimate(const State *s1, const State *s2) const;

            const SpaceInformationPtr &getSpaceInformation() const;

            virtual InformedSamplerPtr allocInformedStateSampler(const ProblemDefinitionPtr &probDefn,
                                                                 unsigned int maxNumberCalls) const;

            virtual void print(std::ostream &out) const;
 
        protected:
            SpaceInformationPtr si_;

            std::string description_;

            Cost threshold_;

            CostToGoHeuristic costToGoFn_;
        };

        Cost goalRegionCostToGo(const State *state, const Goal *goal);

        class MultiOptimizationObjective : public OptimizationObjective
        {
        public:
            MultiOptimizationObjective(const SpaceInformationPtr &si);

            void addObjective(const OptimizationObjectivePtr &objective, double weight);

            std::size_t getObjectiveCount() const;

            const OptimizationObjectivePtr &getObjective(unsigned int idx) const;

            double getObjectiveWeight(unsigned int idx) const;

            void setObjectiveWeight(unsigned int idx, double weight);

            void lock();

            bool isLocked() const;

            Cost stateCost(const State *s) const override;

            Cost motionCost(const State *s1, const State *s2) const override;
 
        protected:
            struct Component
            {
                Component(OptimizationObjectivePtr obj, double weight);
                OptimizationObjectivePtr objective;
                double weight;
            };

            std::vector<Component> components_;

            bool locked_;
 
            // Friend functions for operator overloads for easy multiobjective creation
            friend OptimizationObjectivePtr operator+(const OptimizationObjectivePtr &a,
                                                      const OptimizationObjectivePtr &b);
 
            friend OptimizationObjectivePtr operator*(double weight, const OptimizationObjectivePtr &a);
 
            friend OptimizationObjectivePtr operator*(const OptimizationObjectivePtr &a, double weight);
        };

        OptimizationObjectivePtr operator+(const OptimizationObjectivePtr &a, const OptimizationObjectivePtr &b);

        OptimizationObjectivePtr operator*(double weight, const OptimizationObjectivePtr &a);

        OptimizationObjectivePtr operator*(const OptimizationObjectivePtr &a, double weight);
    }  // namespace base
}  // namespace ompl
 
#endif