protected Size2D arrangeRR(BlockContainer container, Graphics2D g2,
                               RectangleConstraint constraint) {

        // first arrange without constraints, and see if this fits within
        // the required ranges...
        Size2D s1 = arrangeNN(container, g2);
        if (constraint.getWidthRange().contains(s1.width)) {
            return s1;  // TODO: we didn't check the height yet
        }
        else {
            RectangleConstraint c = constraint.toFixedWidth(
                constraint.getWidthRange().getUpperBound()
            );
            return arrangeFR(container, g2, c);