public void add(GRectangle r) {
		if (r.isEmpty()) return;
		if (isEmpty()) {
			setBounds(r);
			return;
		}
		double x2 = Math.max(xc + myWidth, r.xc + r.myWidth);
		double y2 = Math.max(yc + myHeight, r.yc + r.myHeight);
		xc = Math.min(r.xc, xc);
		yc = Math.min(r.yc, yc);
		myWidth = x2 - xc;
		myHeight = y2 - yc;
	}