Use defaulted comparison operators in C++ (#4723)

Comparison operators which compared against every class member variable
now use C++20's default comparison operators.

Also remove operator!= that in C++20 is now auto-generated from operator==.

wpimath/src/main/native/cpp/geometry/Pose2d.cpp

@@ -15,14 +15,6 @@ Transform2d Pose2d::operator-(const Pose2d& other) const {
   return Transform2d{pose.Translation(), pose.Rotation()};
 }
 
-bool Pose2d::operator==(const Pose2d& other) const {
-  return m_translation == other.m_translation && m_rotation == other.m_rotation;
-}
-
-bool Pose2d::operator!=(const Pose2d& other) const {
-  return !operator==(other);
-}
-
 Pose2d Pose2d::RelativeTo(const Pose2d& other) const {
   const Transform2d transform{other, *this};
   return {transform.Translation(), transform.Rotation()};

wpimath/src/main/native/cpp/geometry/Pose3d.cpp

@@ -52,14 +52,6 @@ Transform3d Pose3d::operator-(const Pose3d& other) const {
   return Transform3d{pose.Translation(), pose.Rotation()};
 }
 
-bool Pose3d::operator==(const Pose3d& other) const {
-  return m_translation == other.m_translation && m_rotation == other.m_rotation;
-}
-
-bool Pose3d::operator!=(const Pose3d& other) const {
-  return !operator==(other);
-}
-
 Pose3d Pose3d::operator*(double scalar) const {
   return Pose3d{m_translation * scalar, m_rotation * scalar};
 }

wpimath/src/main/native/cpp/geometry/Quaternion.cpp

@@ -33,10 +33,6 @@ bool Quaternion::operator==(const Quaternion& other) const {
   return std::abs(m_r * other.m_r + m_v.dot(other.m_v)) > 1.0 - 1E-9;
 }
 
-bool Quaternion::operator!=(const Quaternion& other) const {
-  return !operator==(other);
-}
-
 Quaternion Quaternion::Inverse() const {
   return Quaternion{m_r, -m_v(0), -m_v(1), -m_v(2)};
 }

wpimath/src/main/native/cpp/geometry/Rotation3d.cpp

@@ -170,14 +170,6 @@ Rotation3d Rotation3d::operator/(double scalar) const {
   return *this * (1.0 / scalar);
 }
 
-bool Rotation3d::operator==(const Rotation3d& other) const {
-  return m_q == other.m_q;
-}
-
-bool Rotation3d::operator!=(const Rotation3d& other) const {
-  return !operator==(other);
-}
-
 Rotation3d Rotation3d::RotateBy(const Rotation3d& other) const {
   return Rotation3d{other.m_q * m_q};
 }

wpimath/src/main/native/cpp/geometry/Transform2d.cpp

@@ -21,11 +21,3 @@ Transform2d::Transform2d(Pose2d initial, Pose2d final) {
 Transform2d Transform2d::operator+(const Transform2d& other) const {
   return Transform2d{Pose2d{}, Pose2d{}.TransformBy(*this).TransformBy(other)};
 }
-
-bool Transform2d::operator==(const Transform2d& other) const {
-  return m_translation == other.m_translation && m_rotation == other.m_rotation;
-}
-
-bool Transform2d::operator!=(const Transform2d& other) const {
-  return !operator==(other);
-}

wpimath/src/main/native/cpp/geometry/Transform3d.cpp

@@ -31,11 +31,3 @@ Transform3d Transform3d::Inverse() const {
 Transform3d Transform3d::operator+(const Transform3d& other) const {
   return Transform3d{Pose3d{}, Pose3d{}.TransformBy(*this).TransformBy(other)};
 }
-
-bool Transform3d::operator==(const Transform3d& other) const {
-  return m_translation == other.m_translation && m_rotation == other.m_rotation;
-}
-
-bool Transform3d::operator!=(const Transform3d& other) const {
-  return !operator==(other);
-}

wpimath/src/main/native/cpp/geometry/Translation2d.cpp

@@ -23,10 +23,6 @@ bool Translation2d::operator==(const Translation2d& other) const {
          units::math::abs(m_y - other.m_y) < 1E-9_m;
 }
 
-bool Translation2d::operator!=(const Translation2d& other) const {
-  return !operator==(other);
-}
-
 void frc::to_json(wpi::json& json, const Translation2d& translation) {
   json =
       wpi::json{{"x", translation.X().value()}, {"y", translation.Y().value()}};

wpimath/src/main/native/cpp/geometry/Translation3d.cpp

@@ -41,10 +41,6 @@ bool Translation3d::operator==(const Translation3d& other) const {
          units::math::abs(m_z - other.m_z) < 1E-9_m;
 }
 
-bool Translation3d::operator!=(const Translation3d& other) const {
-  return !operator==(other);
-}
-
 void frc::to_json(wpi::json& json, const Translation3d& translation) {
   json = wpi::json{{"x", translation.X().value()},
                    {"y", translation.Y().value()},

wpimath/src/main/native/cpp/trajectory/Trajectory.cpp

@@ -13,16 +13,6 @@
 
 using namespace frc;
 
-bool Trajectory::State::operator==(const Trajectory::State& other) const {
-  return t == other.t && velocity == other.velocity &&
-         acceleration == other.acceleration && pose == other.pose &&
-         curvature == other.curvature;
-}
-
-bool Trajectory::State::operator!=(const Trajectory::State& other) const {
-  return !operator==(other);
-}
-
 Trajectory::State Trajectory::State::Interpolate(State endValue,
                                                  double i) const {
   // Find the new [t] value.
@@ -163,11 +153,3 @@ void frc::from_json(const wpi::json& json, Trajectory::State& state) {
       units::meters_per_second_squared_t{json.at("acceleration").get<double>()};
   state.curvature = units::curvature_t{json.at("curvature").get<double>()};
 }
-
-bool Trajectory::operator==(const Trajectory& other) const {
-  return m_states == other.States();
-}
-
-bool Trajectory::operator!=(const Trajectory& other) const {
-  return !operator==(other);
-}