Retrieving requestAnimationFrame with JavaScript

By  on  

The requestAnimationFrame function has been a major boost to developers creating and managing animations with JavaScript.  Paul Irish has an excellent introduction on requestAnimationFrame -- I highly recommend you read it.  This HTML5Hub post is also very good.  Most browsers now support the animation function but in the case a browser doesn't, you can shim a rough equivalent with setInterval:

var requestAnimationFrame = window.requestAnimationFrame
    || window.webkitRequestAnimationFrame
    || window.mozRequestAnimationFrame
    || window.msRequestAnimationFrame
    || function(callback) { return setTimeout(callback, 1000 / 60); };

requestAnimationFrame was implemented with browser prefixes so we'll check for those if the unprefixed window method isn't there.  If no native implementation exists, a setInterval shim will have to do!

Recent Features

  • By
    Send Text Messages with PHP

    Kids these days, I tell ya.  All they care about is the technology.  The video games.  The bottled water.  Oh, and the texting, always the texting.  Back in my day, all we had was...OK, I had all of these things too.  But I still don't get...

  • By
    Vibration API

    Many of the new APIs provided to us by browser vendors are more targeted toward the mobile user than the desktop user.  One of those simple APIs the Vibration API.  The Vibration API allows developers to direct the device, using JavaScript, to vibrate in...

Incredible Demos

  • By
    Full Width Textareas

    Working with textarea widths can be painful if you want the textarea to span 100% width.  Why painful?  Because if the textarea's containing element has padding, your "width:100%" textarea will likely stretch outside of the parent container -- a frustrating prospect to say the least.  Luckily...

  • By
    Introducing MooTools NextPrev

    One thing I love doing is duplicating OS functionalities. One of the things your OS allows you to do easily is move from one item to another. Most of the time you're simply trying to get to the next or the previous item.


  1. MaxArt

    According to caniuse, Microsoft’s browsers never had a vendor prefixed version of requestAnimationFrame, so we can just keep moz and webkit.

    That’s a very common way to normalize the function, but in most recent implementations requestAnimationFrame passes an argument to the callback function, which is the amount of milliseconds since performance.timing.navigationStart, with micro precision too. This can be very handy for the callback.

    It’s not really possible to perfectly emulate this, but you can get something close if you take note of the epoch time as soon as the script is executed. So this is how I used to polyfill requestAnimationFrame:

    (function(start) {
        window.requestAnimationFrame = function(callback) {
            return setInterval(function() {
                callback(new Date().getTime() - start);
            }, 1000 / 60);
    })(new Date().getTime());

    (Well, not exactly… since most of the times requestAnimationFrame is called again in the callback function, but the function itself takes some milliseconds at least to be executed – because it probably involves some kind of repaint – and you should adjust the time interval accordingly, or you may never hope to even get close to 60 fps.)

    Also, don’t forget to normalize cancelAnimationFrame, which has a nasty variant in some (and maybe forgotten?) WebKit browsers: webkitCancelRequestAnimationFrame.

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!