/**
  * Rotates the camera round the specified coordinates.
  *
  * @param focusX the x coordinate to focus on
  * @param focusY the y coordinate to focus on
  * @param deltaAngle the camera will be rotated by {@code deltaAngle} radians
  */
 public void rotate(double focusX, double focusY, double deltaAngle) {
   synchronized (mutex) {
     Transform focus = Transform.translation(toMetricCoordinates((int) focusX, (int) focusY));
     transform =
         transform
             .multiply(focus)
             .multiply(Transform.zRotation(deltaAngle))
             .multiply(focus.invert());
   }
 }
 private void resetTransform() {
   // Rotate coordinate system to match ROS standard (x is forward, y is left).
   transform = Transform.zRotation(Math.PI / 2).scale(DEFAULT_ZOOM);
 }