public void setLength(final double newLen) {
		int xFac = (x >= 0 ? 1 : -1);
		int yFac = (y >= 0 ? 1 : -1);
		double len = Math.sqrt(x * x + y * y);
		double alpha = Math.asin(Math.abs(x) / len);
		x = Math.sin(alpha) * newLen * xFac;
		y = Math.cos(alpha) * newLen * yFac;
	}