void update() { Transformation transformation = rigidBody.getTransformation(); topGroup.setTransformation(transformation); double s = 1.5 * shaft.getSizeZ(); double[] vec = topGroup.toSpaceFrame(new double[] {0, 0, 1}); orientation.setSizeXYZ(s * vec[0], s * vec[1], s * vec[2]); orientationTrace.addPoint(s * vec[0], s * vec[1], s * vec[2]); frame.render(); }