[wpimath] Make C++ geometry classes immutable (#3249)

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

@@ -20,12 +20,6 @@ Pose2d Pose2d::operator+(const Transform2d& other) const {
   return TransformBy(other);
 }
 
-Pose2d& Pose2d::operator+=(const Transform2d& other) {
-  m_translation += other.Translation().RotateBy(m_rotation);
-  m_rotation += other.Rotation();
-  return *this;
-}
-
 Transform2d Pose2d::operator-(const Pose2d& other) const {
   const auto pose = this->RelativeTo(other);
   return Transform2d(pose.Translation(), pose.Rotation());

wpimath/src/main/native/cpp/geometry/Rotation2d.cpp

@@ -38,24 +38,10 @@ Rotation2d Rotation2d::operator+(const Rotation2d& other) const {
   return RotateBy(other);
 }
 
-Rotation2d& Rotation2d::operator+=(const Rotation2d& other) {
-  double cos = Cos() * other.Cos() - Sin() * other.Sin();
-  double sin = Cos() * other.Sin() + Sin() * other.Cos();
-  m_cos = cos;
-  m_sin = sin;
-  m_value = units::radian_t(std::atan2(m_sin, m_cos));
-  return *this;
-}
-
 Rotation2d Rotation2d::operator-(const Rotation2d& other) const {
   return *this + -other;
 }
 
-Rotation2d& Rotation2d::operator-=(const Rotation2d& other) {
-  *this += -other;
-  return *this;
-}
-
 Rotation2d Rotation2d::operator-() const {
   return Rotation2d(-m_value);
 }

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

@@ -33,21 +33,10 @@ Translation2d Translation2d::operator+(const Translation2d& other) const {
   return {X() + other.X(), Y() + other.Y()};
 }
 
-Translation2d& Translation2d::operator+=(const Translation2d& other) {
-  m_x += other.m_x;
-  m_y += other.m_y;
-  return *this;
-}
-
 Translation2d Translation2d::operator-(const Translation2d& other) const {
   return *this + -other;
 }
 
-Translation2d& Translation2d::operator-=(const Translation2d& other) {
-  *this += -other;
-  return *this;
-}
-
 Translation2d Translation2d::operator-() const {
   return {-m_x, -m_y};
 }
@@ -56,12 +45,6 @@ Translation2d Translation2d::operator*(double scalar) const {
   return {scalar * m_x, scalar * m_y};
 }
 
-Translation2d& Translation2d::operator*=(double scalar) {
-  m_x *= scalar;
-  m_y *= scalar;
-  return *this;
-}
-
 Translation2d Translation2d::operator/(double scalar) const {
   return *this * (1.0 / scalar);
 }
@@ -75,11 +58,6 @@ bool Translation2d::operator!=(const Translation2d& other) const {
   return !operator==(other);
 }
 
-Translation2d& Translation2d::operator/=(double scalar) {
-  *this *= (1.0 / scalar);
-  return *this;
-}
-
 void frc::to_json(wpi::json& json, const Translation2d& translation) {
   json = wpi::json{{"x", translation.X().to<double>()},
                    {"y", translation.Y().to<double>()}};

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

@@ -115,7 +115,7 @@ Trajectory TrajectoryGenerator::GenerateTrajectory(
   const Transform2d flip{Translation2d(), Rotation2d(180_deg)};
   if (config.IsReversed()) {
     for (auto& waypoint : newWaypoints) {
-      waypoint += flip;
+      waypoint = waypoint + flip;
     }
   }
 

wpimath/src/main/native/include/frc/geometry/Pose2d.h

@@ -57,18 +57,6 @@ class Pose2d {
    */
   Pose2d operator+(const Transform2d& other) const;
 
-  /**
-   * Transforms the current pose by the transformation.
-   *
-   * This is similar to the + operator, except that it mutates the current
-   * object.
-   *
-   * @param other The transform to transform the pose by.
-   *
-   * @return Reference to the new mutated object.
-   */
-  Pose2d& operator+=(const Transform2d& other);
-
   /**
    * Returns the Transform2d that maps the one pose to another.
    *

wpimath/src/main/native/include/frc/geometry/Rotation2d.h

@@ -59,18 +59,6 @@ class Rotation2d {
    */
   Rotation2d operator+(const Rotation2d& other) const;
 
-  /**
-   * Adds a rotation to the current rotation.
-   *
-   * This is similar to the + operator except that it mutates the current
-   * object.
-   *
-   * @param other The rotation to add.
-   *
-   * @return The reference to the new mutated object.
-   */
-  Rotation2d& operator+=(const Rotation2d& other);
-
   /**
    * Subtracts the new rotation from the current rotation and returns the new
    * rotation.
@@ -84,18 +72,6 @@ class Rotation2d {
    */
   Rotation2d operator-(const Rotation2d& other) const;
 
-  /**
-   * Subtracts the new rotation from the current rotation.
-   *
-   * This is similar to the - operator except that it mutates the current
-   * object.
-   *
-   * @param other The rotation to subtract.
-   *
-   * @return The reference to the new mutated object.
-   */
-  Rotation2d& operator-=(const Rotation2d& other);
-
   /**
    * Takes the inverse of the current rotation. This is simply the negative of
    * the current angular value.

wpimath/src/main/native/include/frc/geometry/Translation2d.h

@@ -110,18 +110,6 @@ class Translation2d {
    */
   Translation2d operator+(const Translation2d& other) const;
 
-  /**
-   * Adds the new translation to the current translation.
-   *
-   * This is similar to the + operator, except that the current object is
-   * mutated.
-   *
-   * @param other The translation to add.
-   *
-   * @return The reference to the new mutated object.
-   */
-  Translation2d& operator+=(const Translation2d& other);
-
   /**
    * Subtracts the other translation from the other translation and returns the
    * difference.
@@ -135,18 +123,6 @@ class Translation2d {
    */
   Translation2d operator-(const Translation2d& other) const;
 
-  /**
-   * Subtracts the new translation from the current translation.
-   *
-   * This is similar to the - operator, except that the current object is
-   * mutated.
-   *
-   * @param other The translation to subtract.
-   *
-   * @return The reference to the new mutated object.
-   */
-  Translation2d& operator-=(const Translation2d& other);
-
   /**
    * Returns the inverse of the current translation. This is equivalent to
    * rotating by 180 degrees, flipping the point over both axes, or simply
@@ -167,17 +143,6 @@ class Translation2d {
    */
   Translation2d operator*(double scalar) const;
 
-  /**
-   * Multiplies the current translation by a scalar.
-   *
-   * This is similar to the * operator, except that current object is mutated.
-   *
-   * @param scalar The scalar to multiply by.
-   *
-   * @return The reference to the new mutated object.
-   */
-  Translation2d& operator*=(double scalar);
-
   /**
    * Divides the translation by a scalar and returns the new translation.
    *
@@ -205,17 +170,6 @@ class Translation2d {
    */
   bool operator!=(const Translation2d& other) const;
 
-  /*
-   * Divides the current translation by a scalar.
-   *
-   * This is similar to the / operator, except that current object is mutated.
-   *
-   * @param scalar The scalar to divide by.
-   *
-   * @return The reference to the new mutated object.
-   */
-  Translation2d& operator/=(double scalar);
-
  private:
   units::meter_t m_x = 0_m;
   units::meter_t m_y = 0_m;