// 	Author:  James Terry Riendeau, jtriende@wisc.edu
//  		 University of Wisconsin-Madison
//
//	Copyright © 2005 The Board of Regents of the University of Wisconsin System.
//	All rights reserved.  Use of this script restricted to University of Wisconsin 
//  institutions for non-commercial purposes.  This header must remain intact.
//
function FloatDiv(id, sy) {
	var el = document.getElementById ? document.getElementById(id) : document.all ? document.all[id] : document.layers[id];
	var px = document.layers ? "" : "px";

	window[id + "_obj"] = el;

	if (document.layers) { 
		el.style = el;
	}

	el.style.position = "absolute";
	el.sy = el.dy = sy;  // sy = starting y coordinate; dy = delta y coordinate (change in y)

	el.floatThis = function() {
		var windowHeight = (typeof(window.innerWidth) == 'number') ? window.innerHeight : (document.documentElement && document.documentElement.clientHeight ? document.documentElement.clientHeight : (document.body && document.body.clientHeight ? document.body.clientHeight : 0));
		var scroll = typeof( window.pageYOffset ) == 'number' ? window.pageYOffset : (document.body && document.body.scrollTop ? document.body.scrollTop : ( document.documentElement && document.documentElement.scrollTop ? document.documentElement.scrollTop : 0 ));

		scroll += 10;
		this.dy += (scroll - this.dy) / 8;  // increase the divisor for smoother scrolling

		if (this.offsetHeight < windowHeight) {
			if (scroll > this.sy) {
				this.style.top = this.dy + px;
			} else {
				this.style.top = this.sy + px;
			}	
		}

		setTimeout(this.id + "_obj.floatThis()", 40);  // increase timeout to slow scrolling
	}

	return el;
}
			
FloatDiv("menu", 140).floatThis();