public static void setDistanceToTip(JadeTree tree) {
		for (TreeNode node : tree.externalNodes()) {
			double h = 0.0;
			((JadeNode)node).setDistanceToTip(h);
			while (node != null) {
				h += node.getBL();
				if (((JadeNode)node).getDistanceToTip() < h) {
					((JadeNode)node).setDistanceToTip(h);
				}
				node = node.getParent();
			}
		}
	}