gait_generator.h

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#ifndef TOWR_MODELS_GAIT_GENERATOR_H_
#define TOWR_MODELS_GAIT_GENERATOR_H_

#include <memory>
#include <string>
#include <utility>
#include <vector>

namespace towr {

class GaitGenerator {
public:
  using Ptr           = std::shared_ptr<GaitGenerator>;
  using VecTimes      = std::vector<double>;
  using FootDurations = std::vector<VecTimes>;
  using ContactState  = std::vector<bool>;
  using GaitInfo      = std::pair<VecTimes,std::vector<ContactState>>;
  using EE            = uint;

  enum Combos { C0, C1, C2, C3, C4, COMBO_COUNT};

  enum Gaits  {Stand=0, Flight,
               Walk1, Walk2, Walk2E,
               Run2, Run2E, Run1, Run1E, Run3, Run3E,
               Hop1, Hop1E, Hop2, Hop3, Hop3E, Hop5, Hop5E,
               GAIT_COUNT};

  static Ptr MakeGaitGenerator(int leg_count);

  GaitGenerator () = default;
  virtual ~GaitGenerator () = default;

  VecTimes GetPhaseDurations(double T, EE ee) const;

  bool IsInContactAtStart(EE ee) const;

  virtual void SetCombo(Combos combo) = 0;

  void SetGaits(const std::vector<Gaits>& gaits);

protected:
  std::vector<double> times_;

  std::vector<ContactState> contacts_;

  GaitInfo RemoveTransition(const GaitInfo& g) const;

private:
  FootDurations GetPhaseDurations() const;
  virtual GaitInfo GetGait(Gaits gait) const = 0;
  VecTimes GetNormalizedPhaseDurations(EE ee) const;
};

} /* namespace towr */

#endif /* TOWR_MODELS_GAIT_GENERATOR_H_ */