BallJointConstraint.hpp

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#ifndef DART_CONSTRAINT_BALLJOINTCONSTRAINT_HPP_
#define DART_CONSTRAINT_BALLJOINTCONSTRAINT_HPP_

#include <Eigen/Dense>

#include "dart/dynamics/JointConstraint.hpp"
#include "dart/math/MathTypes.hpp"

namespace dart {
namespace dynamics {

class BallJointConstraint : public JointConstraint
{
public:
  BallJointConstraint(
      dynamics::BodyNode* _body, const Eigen::Vector3d& _jointPos);

  BallJointConstraint(
      dynamics::BodyNode* _body1,
      dynamics::BodyNode* _body2,
      const Eigen::Vector3d& _jointPos);

  virtual ~BallJointConstraint();

  // Documentation inherited
  const std::string& getType() const override;

  static const std::string& getStaticType();

protected:
  //----------------------------------------------------------------------------
  // Constraint virtual functions
  //----------------------------------------------------------------------------

  // Documentation inherited
  void update() override;

  // Documentation inherited
  void getInformation(ConstraintInfo* _lcp) override;

  // Documentation inherited
  void applyUnitImpulse(std::size_t _index) override;

  // Documentation inherited
  void getVelocityChange(double* _vel, bool _withCfm) override;

  // Documentation inherited
  void excite() override;

  // Documentation inherited
  void unexcite() override;

  // Documentation inherited
  void applyImpulse(double* _lambda) override;

  // Documentation inherited
  bool isActive() const override;

  // Documentation inherited
  dynamics::SkeletonPtr getRootSkeleton() const override;

  // Documentation inherited
  void uniteSkeletons() override;

private:
  Eigen::Vector3d mOffset1;

  Eigen::Vector3d mOffset2;

  Eigen::Vector3d mViolation;

  Eigen::Matrix<double, 3, 6> mJacobian1;

  Eigen::Matrix<double, 3, 6> mJacobian2;

  double mOldX[3];

  std::size_t mAppliedImpulseIndex;

public:
  // To get byte-aligned Eigen vectors
  EIGEN_MAKE_ALIGNED_OPERATOR_NEW
};

} // namespace dynamics
} // namespace dart

#endif // DART_CONSTRAINT_BALLJOINTCONSTRAINT_HPP_