    /*
     * $example: Declare a structure to hold mouse rotation coefficients, and
     * a mouse region configured with an origin that matches that of JOGL's
     * windowing system.
     */

    final JCameraRotationCoefficientsMutable rotations =
      JCameraRotationCoefficientsMutable.create();
    final AtomicReference<JCameraFPSStyleMouseRegion> mouse_region =
      new AtomicReference<>(
        JCameraFPSStyleMouseRegion.of(
          JCameraScreenOrigin.SCREEN_ORIGIN_TOP_LEFT,
          640.0,
          480.0));

