gistfile1.js

    getWindowScroll: function() {
        var T, L, W, H;
        var w = window;

        with (w.document) {
            if (w.document.documentElement && documentElement.scrollTop) {
                T = documentElement.scrollTop;
                L = documentElement.scrollLeft;
            } else if (w.document.body) {
                T = body.scrollTop;
                L = body.scrollLeft;
            }   

            if (w.innerWidth) {
                W = w.innerWidth;
                H = w.innerHeight;
            } else if (w.document.documentElement && documentElement.clientWidth) {
                W = documentElement.clientWidth;
                H = documentElement.clientHeight;
            } else {
                W = body.offsetWidth;
                H = body.offsetHeight
            }   
        }   

        return {
            top: T,
            left: L,
            width: W,
            height: H
        };  
    },