Files
allwpilib/wpilibc/src/main/native/cpp/trajectory/constraint/EllipticalRegionConstraint.cpp
2020-06-29 22:25:09 -07:00

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2.3 KiB
C++

/*----------------------------------------------------------------------------*/
/* Copyright (c) 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. */
/*----------------------------------------------------------------------------*/
#include "frc/trajectory/constraint/EllipticalRegionConstraint.h"
#include <limits>
#include <units/math.h>
using namespace frc;
EllipticalRegionConstraint::EllipticalRegionConstraint(
const Translation2d& center, units::meter_t xWidth, units::meter_t yWidth,
const Rotation2d& rotation, const TrajectoryConstraint& constraint)
: m_center(center),
m_radii(xWidth / 2.0, yWidth / 2.0),
m_constraint(constraint) {
m_radii = m_radii.RotateBy(rotation);
}
units::meters_per_second_t EllipticalRegionConstraint::MaxVelocity(
const Pose2d& pose, units::curvature_t curvature,
units::meters_per_second_t velocity) const {
if (IsPoseInRegion(pose)) {
return m_constraint.MaxVelocity(pose, curvature, velocity);
} else {
return units::meters_per_second_t(std::numeric_limits<double>::infinity());
}
}
TrajectoryConstraint::MinMax EllipticalRegionConstraint::MinMaxAcceleration(
const Pose2d& pose, units::curvature_t curvature,
units::meters_per_second_t speed) const {
if (IsPoseInRegion(pose)) {
return m_constraint.MinMaxAcceleration(pose, curvature, speed);
} else {
return {};
}
}
bool EllipticalRegionConstraint::IsPoseInRegion(const Pose2d& pose) const {
// The region (disk) bounded by the ellipse is given by the equation:
// ((x-h)^2)/Rx^2) + ((y-k)^2)/Ry^2) <= 1
// If the inequality is satisfied, then it is inside the ellipse; otherwise
// it is outside the ellipse.
// Both sides have been multiplied by Rx^2 * Ry^2 for efficiency reasons.
return units::math::pow<2>(pose.Translation().X() - m_center.X()) *
units::math::pow<2>(m_radii.Y()) +
units::math::pow<2>(pose.Translation().Y() - m_center.Y()) *
units::math::pow<2>(m_radii.X()) <=
units::math::pow<2>(m_radii.X()) * units::math::pow<2>(m_radii.Y());
}