js runner

by sthag

HTML

<div>runner</div>

CSS

div {
    position: absolute;
}

JavaScript

var div = $('div');
var a = 0;
var delay = (1000 / 30);
var now, before = new Date();

setInterval(function() {
    now = new Date();
    var elapsedTime = (now.getTime() - before.getTime());
    if(elapsedTime > delay)
        //Recover the motion lost while inactive.
        a += Math.floor(elapsedTime/delay);
    else
        a++;
    div.css("left", a);
    before = new Date();    
}, delay);