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allwpilib/wpimath/src/main/native/include/frc/spline/QuinticHermiteSpline.h

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3.1 KiB
C++

/*----------------------------------------------------------------------------*/
/* Copyright (c) 2019-2020 FIRST. All Rights Reserved. */
/* Open Source Software - may be modified and shared by FRC teams. The code */
/* must be accompanied by the FIRST BSD license file in the root directory of */
/* the project. */
/*----------------------------------------------------------------------------*/
#pragma once
#include <array>
#include "Eigen/Core"
#include "frc/spline/Spline.h"
namespace frc {
/**
* Represents a hermite spline of degree 5.
*/
class QuinticHermiteSpline : public Spline<5> {
public:
/**
* Constructs a quintic hermite spline with the specified control vectors.
* Each control vector contains into about the location of the point, its
* first derivative, and its second derivative.
*
* @param xInitialControlVector The control vector for the initial point in
* the x dimension.
* @param xFinalControlVector The control vector for the final point in
* the x dimension.
* @param yInitialControlVector The control vector for the initial point in
* the y dimension.
* @param yFinalControlVector The control vector for the final point in
* the y dimension.
*/
QuinticHermiteSpline(std::array<double, 3> xInitialControlVector,
std::array<double, 3> xFinalControlVector,
std::array<double, 3> yInitialControlVector,
std::array<double, 3> yFinalControlVector);
protected:
/**
* Returns the coefficients matrix.
* @return The coefficients matrix.
*/
Eigen::Matrix<double, 6, 6> Coefficients() const override {
return m_coefficients;
}
private:
Eigen::Matrix<double, 6, 6> m_coefficients =
Eigen::Matrix<double, 6, 6>::Zero();
/**
* Returns the hermite basis matrix for quintic hermite spline interpolation.
* @return The hermite basis matrix for quintic hermite spline interpolation.
*/
static Eigen::Matrix<double, 6, 6> MakeHermiteBasis() {
// clang-format off
static const auto basis = (Eigen::Matrix<double, 6, 6>() <<
-06.0, -03.0, -00.5, +06.0, -03.0, +00.5,
+15.0, +08.0, +01.5, -15.0, +07.0, +01.0,
-10.0, -06.0, -01.5, +10.0, -04.0, +00.5,
+00.0, +00.0, +00.5, +00.0, +00.0, +00.0,
+00.0, +01.0, +00.0, +00.0, +00.0, +00.0,
+01.0, +00.0, +00.0, +00.0, +00.0, +00.0).finished();
// clang-format on
return basis;
}
/**
* Returns the control vector for each dimension as a matrix from the
* user-provided arrays in the constructor.
*
* @param initialVector The control vector for the initial point.
* @param finalVector The control vector for the final point.
*
* @return The control vector matrix for a dimension.
*/
static Eigen::Matrix<double, 6, 1> ControlVectorFromArrays(
std::array<double, 3> initialVector, std::array<double, 3> finalVector) {
return (Eigen::Matrix<double, 6, 1>() << initialVector[0], initialVector[1],
initialVector[2], finalVector[0], finalVector[1], finalVector[2])
.finished();
}
};
} // namespace frc