void scrollToNode(ImageDisplay node)
private void scrollToNode(Rectangle childBounds, ImageDisplay parent, boolean isRoot)
    void scrollToNode(ImageDisplay node)    {        if (node == null) throw new IllegalArgumentException("No node.");        ImageDisplay parent = node.getParentDisplay();        if (parent != null)            scrollToNode(node.getBounds(), parent,                    (parent.getParentDisplay() == null));     }