TrochoidStateSpace.h

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/* Author: Jaeyoung Lim */
 
#ifndef OMPL_BASE_SPACES_TROCHOID_STATE_SPACE_
#define OMPL_BASE_SPACES_TROCHOID_STATE_SPACE_
 
#include "ompl/base/spaces/SE2StateSpace.h"
#include "ompl/base/MotionValidator.h"
#include <boost/math/constants/constants.hpp>
#include <optional>
 
namespace ompl
{
    namespace base
    {
        class TrochoidStateSpace : public SE2StateSpace
        {
        public:
            enum TrochoidPathSegmentType
            {
                TROCHOID_LEFT = 0,
                TROCHOID_STRAIGHT = 1,
                TROCHOID_RIGHT = 2
            };

            static const std::vector<std::vector<TrochoidPathSegmentType>> &dubinsPathType();
            class PathType
            {
            public:
                PathType(const std::vector<TrochoidPathSegmentType> &type = dubinsPathType()[0], double tA = 0.,
                         double p = std::numeric_limits<double>::max(), double tB = 0., double t_2pi = 0.)
                  : type_(&type)
                {
                    length_[0] = tA;
                    length_[1] = p;
                    length_[2] = t_2pi - tB;
                    assert(tA >= 0.);
                    assert(p >= 0.);
                    assert(t_2pi - tB >= 0.);
                }
                double length() const
                {
                    return length_[0] + length_[1] + length_[2];
                }
 
                friend std::ostream &operator<<(std::ostream &os, const PathType &path);
                const std::vector<TrochoidPathSegmentType> *type_;
                double length_[3];
                bool reverse_{false};
            };
 
            TrochoidStateSpace(double turningRadius = 1.0, double windRatio = 0.0, double windDirection = 0.0,
                               bool isSymmetric = false)
              : rho_(turningRadius), eta_(windRatio), psi_w_(windDirection), isSymmetric_(isSymmetric)
            {
                setName("Trochoid" + getName());
                type_ = STATE_SPACE_TROCHOID;
            }
 
            bool isMetricSpace() const override
            {
                return false;
            }
 
            double distance(const State *state1, const State *state2) const override;
            static double distance(const State *state1, const State *state2, double radius, double wind_ratio,
                                   double wind_heading);
            static double symmetricDistance(const State *state1, const State *state2, double radius, double wind_ratio,
                                            double wind_heading);
 
            void interpolate(const State *from, const State *to, double t, State *state) const override;
            virtual void interpolate(const State *from, const State *to, double t, bool &firstTime, PathType &path,
                                     State *state) const;
            virtual void interpolate(const State *from, const PathType &path, double t, State *state, double radius,
                                     double wind_ratio, double wind_heading) const;
 
            bool hasSymmetricDistance() const override
            {
                return isSymmetric_;
            }
 
            bool hasSymmetricInterpolate() const override
            {
                return isSymmetric_;
            }
 
            unsigned int validSegmentCount(const State *state1, const State *state2) const override;
 
            void sanityChecks() const override
            {
                double zero = std::numeric_limits<double>::epsilon();
                double eps = std::numeric_limits<float>::epsilon();
                int flags = ~(STATESPACE_INTERPOLATION | STATESPACE_TRIANGLE_INEQUALITY | STATESPACE_DISTANCE_BOUND);
                if (!isSymmetric_)
                    flags &= ~STATESPACE_DISTANCE_SYMMETRIC;
                StateSpace::sanityChecks(zero, eps, flags);
            }

            PathType getPath(const State *state1, const State *state2, bool periodic = false) const;
            static PathType getPath(const State *state1, const State *state2, double radius, double wind_ratio,
                                    double wind_heading, bool periodic = false);
 
        protected:
            double rho_;

            double eta_;

            double psi_w_;

            bool isSymmetric_;
        };
    }  // namespace base
}  // namespace ompl
 
#endif