Get absolute screen coordinates

screen_coords.js

function GetScreenCordinates(obj) {
    var p = {};
    p.x = obj.offsetLeft;
    p.y = obj.offsetTop;
    while (obj.offsetParent) {
        p.x = p.x + obj.offsetParent.offsetLeft;
        p.y = p.y + obj.offsetParent.offsetTop;
        if (obj == document.getElementsByTagName("body")[0]) {
            break;
        }
        else {
            obj = obj.offsetParent;
        }
    }
    return p;
}