DynamicPath.h

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#ifndef DYNAMIC_PATH_H
#define DYNAMIC_PATH_H

#include "ParabolicRamp.h"
#include <KrisLibrary/math/random.h>

namespace ParabolicRamp {

class FeasibilityCheckerBase
{
 public:
  virtual ~FeasibilityCheckerBase() {}
  virtual bool ConfigFeasible(const Vector& x)=0;
  virtual bool SegmentFeasible(const Vector& a,const Vector& b)=0;
};

class DistanceCheckerBase
{
 public:
  virtual ~DistanceCheckerBase() {}
  virtual Real ObstacleDistanceNorm() const { return Math::Inf; }
  virtual Real ObstacleDistance(const Vector& x)=0;
};

bool CheckRamp(const ParabolicRampND& ramp,FeasibilityCheckerBase* feas,DistanceCheckerBase* distance,int maxiters);

bool CheckRamp(const ParabolicRampND& ramp,FeasibilityCheckerBase* space,Real tol);


class RampFeasibilityChecker
{
 public:
  RampFeasibilityChecker(FeasibilityCheckerBase* feas,Real tol);
  RampFeasibilityChecker(FeasibilityCheckerBase* feas,DistanceCheckerBase* distance,int maxiters);
  bool Check(const ParabolicRampND& x);

  FeasibilityCheckerBase* feas;
  Real tol;
  DistanceCheckerBase* distance;
  int maxiters;
};

class RandomNumberGeneratorBase
{
 public:
  virtual Real Rand() { return Math::Rand(); }
};


class DynamicPath
{
 public:
  DynamicPath();
  void Init(const Vector& velMax,const Vector& accMax);
  void SetJointLimits(const Vector& qMin,const Vector& qMax);
  inline void Clear() { ramps.clear(); }
  inline bool Empty() const { return ramps.empty(); }
  inline const Vector& StartConfig() const { return ramps.front().x0; }
  inline const Vector& EndConfig() const { return ramps.back().x1; }
  inline const Vector& StartVelocity() const { return ramps.front().dx0; }
  inline const Vector& EndVelocity() const { return ramps.back().dx1; }
  Real GetTotalTime() const;
  int GetSegment(Real t,Real& u) const;
  void Evaluate(Real t,Vector& x) const;
  void Derivative(Real t,Vector& dx) const;
  void Accel(Real t,Vector& ddx) const;
  bool SolveMinTime(const Vector& x0,const Vector& dx0,const Vector& x1,const Vector& dx1);
  bool SolveMinAccel(const Vector& x0,const Vector& dx0,const Vector& x1,const Vector& dx1,Real endTime);
  bool SetMilestones(const std::vector<Vector>& x);
  bool SetMilestones(const std::vector<Vector>& x,const std::vector<Vector>& dx);
  void GetMilestones(std::vector<Vector>& x,std::vector<Vector>& dx) const;
  void Append(const Vector& x);
  void Append(const Vector& x,const Vector& dx);
  void Concat(const DynamicPath& suffix);
  void Split(Real t,DynamicPath& before,DynamicPath& after) const;
  bool TryShortcut(Real t1,Real t2,RampFeasibilityChecker& check);
  int Shortcut(int numIters,RampFeasibilityChecker& check);
  int Shortcut(int numIters,RampFeasibilityChecker& check,RandomNumberGeneratorBase* rng);
  int ShortCircuit(RampFeasibilityChecker& check);
  int OnlineShortcut(Real leadTime,Real padTime,RampFeasibilityChecker& check);
  int OnlineShortcut(Real leadTime,Real padTime,RampFeasibilityChecker& check,RandomNumberGeneratorBase* rng);

  //Shortcutting technique with wrapping ranges, useful for angles.  Set
  //modulus = Inf to indicate that the range should not be wrapped.
  //Note: does not allow intermediate segments to wrap twice, even if that
  //would be more efficient
  int WrappedShortcut(const std::vector<Real>& modulus,int numIters,RampFeasibilityChecker& check,RandomNumberGeneratorBase* rng);

  bool IsValid() const;

  Vector xMin,xMax,velMax,accMax;
  std::vector<ParabolicRampND> ramps;
};

} //namespace ParabolicRamp

#endif