requestAnimFrame() shim.

gistfile1.js

// see http://paulirish.com/2011/requestanimationframe-for-smart-animating/

// shim layer with setTimeout fallback

    window.requestAnimFrame = (function(){
      return  window.requestAnimationFrame       || 
              window.webkitRequestAnimationFrame || 
              window.mozRequestAnimationFrame    || 
              window.oRequestAnimationFrame      || 
              window.msRequestAnimationFrame     || 
              function(callback, element){
                window.setTimeout(function(){
                    callback(+new Date);
                }, 1000 / 60);
              };
    })();

I've since updated this gist to remove the timeundefined issue as it was specific to Chrome 10 which is now dead and gone. hooray for software updates!

Don't use this

use this:

https://gist.github.com/1579671