public Shape getUpPointerShape() {
        Path2D shape = new Path2D.Double();
        shape.moveTo(+0.50 * SIZE, -0.28 * SIZE);
        shape.lineTo(+0.50 * SIZE + 0.7 * POINTER_SIZE, -0.28 * SIZE + POINTER_SIZE);
        shape.lineTo(+0.50 * SIZE - 0.7 * POINTER_SIZE, -0.28 * SIZE + POINTER_SIZE);