https://www.afmq.com/js/dimension_fd.js

1// Utf-8 é 
2//*
3// MODAL WINDOW
4// By Francois Dupras
5function getScrollOffset() {
6  var scrOfX = 0, scrOfY = 0;
7  if( typeof( window.pageYOffset ) == 'number' ) {
8    //Netscape compliant
9    scrOfY = window.pageYOffset;
10    scrOfX = window.pageXOffset;
11  } else if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) {
12    //DOM compliant
13    scrOfY = document.body.scrollTop;
14    scrOfX = document.body.scrollLeft;
15  } else if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) {
16    //IE6 standards compliant mode
17    scrOfY = document.documentElement.scrollTop;
18    scrOfX = document.documentElement.scrollLeft;
19  }
20  return {x:scrOfX, y:scrOfY, left:scrOfX, top:scrOfY};
21}
22
23function getWindowSize() {
24	var myWidth = 0, myHeight = 0;
25	if( typeof( window.innerWidth ) == 'number' ) {
26		//Non-IE
27		myWidth = window.innerWidth;
28		myHeight = window.innerHeight;
29	} else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
30		//IE 6+ in 'standards compliant mode'
31		myWidth = document.documentElement.clientWidth;
32		myHeight = document.documentElement.clientHeight;
33	} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
34		//IE 4 compatible
35		myWidth = document.body.clientWidth;
36		myHeight = document.body.clientHeight;
37	}
38	return {width:myWidth, height:myHeight};
39}
40
41function findPos(obj) {
42	var curleft = curtop = 0;
43	if (obj.offsetParent) {
44		do {
45			curleft += obj.offsetLeft;
46			curtop += obj.offsetTop;
47		} while (obj = obj.offsetParent);
48	}
49	return {x:curleft, y:curtop};
50}