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Hi, I’m Rob Hawkes and I’m here today to talk about the technologies behind HTML5 and
JavaScript games.
I’m also here to show you why these technologies aren’t just for games and how they can be
useful in day-to-day Web development.

I work at Mozilla, a non-profit fighting for a better Web. The same guys who make Firefox.
I’m pretty fond of Mozilla. So much so that my girlfriend made me a chicken and leek pie with
extra Firefox goodness.
It was delicious.

I’m not sure how much time we’ll have for questions at the end, but feel free to grab me in
person after the talk or on Twitter.
These slides will go online after this talk, they include links to more information on the
technologies covered.
I’ll put all the details up at the end.

Before we move on I just have a quick disclaimer.
This whole talk is about HTML5 and JavaScript as technologies used in the creation of games.
They’re technologies that are intrinsically linked to each other by nature, but saying HTML5
and JavaScript every single time makes my head hurt.
So instead I’ll just be saying HTML5.
Just bear in mind that whenever I mention HTML5 I’m also referring to JavaScript as well.

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Now I think it’s safe to say that games are pretty important, for many reasons.

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One of those reasons is that they are universal.
There are games out there to suit all walks of life; whether that’s a board game, card game,
or computer game. It’s all the same.
Over the years, I’ve played all sorts of games that each meant something different to me at
that point in life.

It’s memories from games like Paperboy on the ZX Spectrum and its amazing noises and epic
loading times.
I sorely miss those days.

And Bomberman on the SNES, which really got me addicted to gaming.

And Lylat Wars on the Nintendo 64. Star Fox for the non-European folk.
Do a barrel roll!

And the original Sim City.
I don’t bare think about the hours I lost to that game, building a city on what I’ve only just
noticed was an incredibly muddy landscape.

And Red Alert, one of the first games I owned that let me play with others over the Internet. It
was great fun!
And probably one of my all-time favourites, along with the original Command and Conquer.
Plus, it had an awesome soundtrack.

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Another reason is that they are incredibly fun to play.
This is probably because they tap in to to our addictive, competitive personalities.
I don’t know anyone who hates games.

However, I do know people who hate fruit. A lot.
One of my favourite games at the moment is Fruit Ninja on the Kinect.
It pretty much justifies the Kinect’s existence.
I had a few friends over the other week and we all ended the weekend with Fruit Ninja-related
injuries.
It was worth it though.

Trailer for Fruit Ninja - http://www.youtube.com/watch?v=UzsmDfKzk7M

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Aside from being universal and fun, games are important because they push the boundaries
of what’s possible with today’s technology.
Games are one of the only things that deliberately use every ounce of your computer’s
capabilities; from graphics, to processing power, to RAM, even to disk space.
As computers constantly get better, games improve to use up the new improvements in
speed and power.
And computer hardware is improved, in part, because of the desire to create faster and more
realistic games.

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2002
For example, this is Battlefield 3. It’s one of the most powerful and ‘realistic’ games out to
date.
It came out in 2011.
Compare that to Battlefield 1942, which came out back in 2002.
Notice the difference? There’s barely 9 years between them and yet it’s quite clear that
Battlefield 3 is far superior, at least visually.

Minimum specs
2400
2000
500 512
128
32
Processor (Mhz) Graphics (MB) RAM (MB)
Battlefield 1942 (2002) Battlefield 3 (2011)
Just take a look at the minimum hardware specs of Battlefield 1942 and Battlefield 3.
In just 9 years we’ve pushed computers so far that the minimum requirement for a game
today is way beyond what was even possible back in 2002.

Recommended specs
4000
2400 2400
2000
1024
500 512
32 128
Processor (Mhz) Graphics (MB) RAM (MB)
Battlefield 1942 (2002) Battlefield 3 (2011) Battlefield 3 - Recommended (2011)
And the minimum specs don’t even produce anything near the quality that you saw on the
previous slide.
For that you need even more powerful hardware.
These are the recommended specs for Battlefield 3. Aside from processor speed, they are at
least double everything else.
We’re talking state of the art technology here, and even this still won’t run the game at its full
potential.

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We now have more and faster processors than ever before, we have insanely powerful
graphics cards, and so much RAM we don’t know what to do with it.
The improvements that games help bring about in computer hardware mean that we can now
do some really cool stuff on the Web.
Without games, there would be little need to continue pushing Web technologies; like faster
JavaScript, or hardware accelerated CSS and multimedia rendering.

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So in a rather long-winded way, my point here is that you need to play more games.
You’re making the Web better and having fun at the same time. Win win!

Now you’re probably thinking, “Who is this dude, and why is he waffling on about games? I
want to hear about HTML5, damnit!”
Let’s make that happen.

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The number of HTML5 games out there is growing every day.
I’d like to show you a selection of my favourites, just a tiny amount of what’s out there.

Quake II
Fully-functional multiplayer Quake II port.
http://code.google.com/p/quake2-gwt-port/

Cut The Rope
Cut The Rope, ported from iOS.
http://www.cuttherope.ie

Bejeweled
Bejeweled is a massively popular game on a whole variety of platforms.
Popcap recently released a purely HTML5 version.
http://bejeweled.popcap.com/html5

Command & Conquer
Command & Conquer: Tiberium Alliances is a HTML5 game from EA that is part real-time
strategy, part Farmville.
http://alliances.commandandconquer.com

GT Racing
GT Racing: Motor Academy is a 3D racing game by Gameloft and Mandreel.
http://www.mandreel.com/?page_id=1312

BrowserQuest
BrowserQuest is a massively-multiplayer RPG that Mozilla recently launched to the public.
It works great on mobile and desktop devices but what’s even better is that, aside from being
an addictive game, the entire source code is on GitHub.
http://browserquest.mozilla.org
https://github.com/mozilla/BrowserQuest
http://hacks.mozilla.org/2012/03/browserquest/

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There are key technologies that are involved in the development of HTML5 games like the
ones you just saw.
I’m going highlight a few of the ones that also translate well into the realm of standard Web
development.

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Canvas is a 2D bitmap graphics platform.
It’s quite amazing what can be done with such simple drawing and image manipulation tools.
In games this is used to do things like drawing sprites and performing image manipulation
on the fly.
https://developer.mozilla.org/en/HTML/Canvas

Silk is a stunning example of what can be achieved by combining the simple drawing tools
available in canvas.
http://weavesilk.com

Close Pixelate is a canvas app that lets you manipulate images on–the-fly to create a
pixelated effect.
http://desandro.com/resources/close-pixelate/

You can even use canvas just for simple effects on a standard Web page.
David Desandro uses canvas to draw curved lines on his portfolio that indicate areas of focus.
Before canvas you’d have had to have used static images or complex techniques to achieve
this.
http://desandro.com/portfolio/

Last year I helped HTML5 Doctor implement a canvas-based rollover effect on their element
index.
With canvas, we were able to create custom-shaped rollovers that were entirely dynamic.
We also cached these canvas-generated images so they didn’t need to be created on every
page load.
http://html5doctor.com

Canvas
<canvas id='myCanvasElement' width='400' height='400'></canvas>
Using canvas is very straight forward.
The first thing you need to do is add a canvas DOM element to your HTML page.

Canvas
var canvas = document.getElementById('myCanvasElement');
var ctx = canvas.getContext('2d');
ctx.fillStyle = "rgb(200,0,0)";
ctx.fillRect(10, 10, 55, 50);
ctx.fillStyle = "rgba(0, 0, 200, 0.5)";
ctx.fillRect(30, 30, 55, 50);
From there you can then access the canvas through JavaScript to draw on it and do other cool
stuff.
This is small canvas demo that draws a solid red square underneath a blue one with half
transparency.
‘myCanvasElement’ refers to a HTML <canvas> element that you’ll need to place in your
HTML file somewhere. In this example, I’m assuming that you’ve already done that.

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WebGL brings the ability to provide advanced 3D graphics directly within the browser.
Games use this to create immersive 3D worlds and models, or for accelerated 2D graphics.
https://developer.mozilla.org/en/WebGL

HelloRacer is a little game that lets you drive a Formula One car around your browser. It’s a
beautiful example of WebGL in action.
http://helloracer.com/webgl/

Rome is a music video created with WebGL. It’s an amazing example of what the technology
can achieve in a real-world situation given a large team.
http://ro.me

Tinkercad is probably the best use of WebGL that I’ve seen in a production situation.
It’s a Web app that allows you to create 3D objects in your browser using WebGL, then get
them printed and sent to your doorstep in just a few simple clicks. It’s seriously awesome.
https://tinkercad.com

Eve Online WebGL ship viewer.
http://www.eveonline.com/universe/spaceships/

Both Google Maps and Nokia have recently added support for WebGL. The Nokia version is
particularly impressive because they fully render and texture 3D shapes of buildings.
http://support.google.com/maps/bin/answer.py?hl=en&answer=1630790
http://maps.nokia.com/webgl/

Undulating monkey by Paul Lewis.
http://lab.aerotwist.com/webgl/undulating-monkey/

I’m not going to lie, WebGL isn’t the easiest thing to learn. Then again, no raw 3D code is
that simple.
Instead, I recommend checking out a library called three.js which abstracts WebGL and makes
it much easier to implement.
https://github.com/mrdoob/three.js/

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requestAnimationFrame is the new, better way of managing animation in JavaScript.
Instead of constantly running a setTimeout or setInterval function, which lack performance
and spike CPU usage, requestAnimationFrame puts the browser in control of things and
keeps things running smoothly.
https://developer.mozilla.org/en/DOM/window.requestAnimationFrame

requestAnimationFrame
function update(timestamp) {
// DO SOMETHING
window.mozRequestAnimationFrame(update);
}
window.mozRequestAnimationFrame(update);
In this example, I’m only using the Mozilla prefixed version of requestAnimationFrame. In
reality, there’s a really good shim by Paul Irish that handles cross-browser
requestAnimationFrame.
http://paulirish.com/2011/requestanimationframe-for-smart-animating/

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HTML5 audio allows for plugin-less audio.
For games, this would be used for sound effects and background music.
Audio data APIs implemented by Mozilla and Google allow for manipulation of audio and
much more fine-grained control.
https://developer.mozilla.org/en/HTML/Element/audio
https://developer.mozilla.org/en/Introducing_the_Audio_API_Extension

This is something I made especially for the ASSEMBLY 2011 event in Finland.
It’s an audio visualiser that uses WebGL and the HTML5 Audio Data API.
http://robhawkes.github.com/webgl-html5-audio-visualiser/

Canvas.fm uses Soundcloud, the Audio Data API and canvas to render music as it plays.
http://canvas.fm

Audio
<audio id='myAudioElement' controls>
<source src='audiofile.ogg' type='audio/ogg'>
</audio>
Like canvas, using audio is also straight forward.
The first thing you need to do is add an audio DOM element to your HTML page.

Audio
var audio = document.getElementById('myAudioElement');
audio.play();
audio.pause();
From there you can then access the audio element through JavaScript to control it.

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Methods like the application cache, Local Storage, and IndexedDB are great for storing
relatively large quantities of data locally.
This way you can cache data and allow the website to pick up where the user left off.
https://developer.mozilla.org/en/DOM/Storage
https://developer.mozilla.org/en/Offline_resources_in_Firefox
https://developer.mozilla.org/en/IndexedDB

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WebSockets can be used for the real-time communication between a browser client and
server.
For games, this would be used for fast-paced multiplayer functionality.
https://developer.mozilla.org/en/WebSockets

GoSquared use WebSockets for real-time website analytics.
http://www.gosquared.com

WebSockets
var ws = new WebSocket('http://example.com/socketserver');
ws.send('This message is sent to the WebSocket server');
ws.onmessage = function (event) {
console.log(event.data);
}
WebSockets are created entirely from JavaScript without the need to add elements to the
HTML page.
A new WebSocket connection can be opened by calling the ‘new WebSocket’ constructor and
passing it the URL to the WebSocket server.
From there you can call the ‘send’ method to push data to the server.
Or listen for the ‘onmessage’ event to handle data pushed to you from the server.

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Web Workers allow you to run JavaScript in separate background threads.
This allows you to offload computationally-heavy tasks with a single worker, or tackle large
quantities of data in a fraction of the time by spreading tasks over multiple workers.
Another benefit of doing this is that you don’t lock up the browser during heavy tasks,
meaning a user can still interact with things and get stuff done.
https://developer.mozilla.org/En/Using_web_workers

Web Workers
var worker = new Worker('my-worker.js');
worker.onmessage = function(event) {
console.log('Worker message: ' + event.data);
};
Web Workers, like WebSockets, are created entirely through JavaScript.
You create a new worker by calling the ‘new Worker’ constructor and passing it the path to a
JavaScript file.
You can then listen to the ‘onmessage’ event that will be fired every time the worker script
sends data using a ‘postMessage’ method.

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The Full Screen API allows you to expand any HTML element to fill the users screen, even if
the browser isn’t running full screen itself.
For games, this is great because you can make the small canvas element fill the entire screen.
Outside of games, this is useful for video elements and Web applications.
https://bugzilla.mozilla.org/show_bug.cgi?id=545812
http://blog.pearce.org.nz/2011/09/mozilla-full-screen-api-progress-update.html
https://wiki.mozilla.org/Platform/Features/Full_Screen_APIs

Full Screen API
var canvas = document.getElementById('myCanvasElement');
if (canvas.requestFullscreen) {
canvas.requestFullscreen();
} else if (canvas.mozRequestFullScreen) {
canvas.mozRequestFullScreen();
} else if (canvas.webkitRequestFullScreen) {
canvas.webkitRequestFullScreen();
}
The Full Screen API can be requested from any DOM element.
In this example you’re asking a canvas element to expand to fill the screen.
One thing to note is that you can’t just make any element fill the screen whenever you want.
Right now, the user has to click or press a key to initiate the Full Screen API.

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The Screen Orientation API allows you to do things like changing and locking, you guessed it,
the orientation of the screen.
Before now, it’s been incredibly difficult to lock orientation on a website or game using
nothing but JavaScript.
https://bugzilla.mozilla.org/show_bug.cgi?id=740188
http://dvcs.w3.org/hg/screen-orientation/raw-file/default/Overview.html

Screen Orientation API
if (screen.mozLockOrientation) {
screen.mozLockOrientation('landscape');
}
The Screen Orientation API is another relatively simple one.
It just landed in Firefox Nightly on mobile.
All you need to do is call the ‘lockOrientation’ method of the screen object and pass it a
orientation string.
It’s important to note that you also need to be using the Full Screen API for the orientation
lock to work.

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Node is often used as a multiplayer game server, controlling the logic and handling the
WebSockets connections to the players.
It can be used for player authentication and the storage of data so gameplay can persist over
multiple game sessions.
This is all made relatively easy with great third-party modules, like Socket.IO for WebSockets,
and others that handle Redis and MongoDB for storage, for example.
http://nodejs.org

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The concept of Web apps is something that is gaining a lot of traction at the moment.
It’s no doubt this this traction is as a result of the success of native applications and games
on the desktop and mobile, particularly with iOS and Android.
https://developer.mozilla.org/en/Apps

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Something that needs to be tackled with Web apps is how to make them feel like real
applications rather than glorified websites.
One way that is being considered is completely removing the browser chrome and running
the application in it’s own window.
This will effectively mean that you have full control of the app UI and it won’t look like it’s
being run in a browser.

At Mozilla we call this WebRT, which stands for Web Run-Time.
By using WebRT you can install a Web app directly into the OS just like you would a native
application.
The WebRT app will look and feel like a native application when launched but will actually be
running a browser rendering engine behind the scenes.
This is an example of my game Rawkets running as a WebRT app with the Firefox rendering
engine. Notice the lack of browser UI.
https://developer.mozilla.org/en/Apps/Apps_architecture#Web_runtime

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A lot of game developers want to target browsers but don’t want to rewrite their existing
games in JavaScript.
To help this process, various methods of converting an existing code-base to JavaScript are
starting to appear.
However, these methods also apply to non-games. Many people are now converting utility
scripts from native languages over to JavaScript. Things like SQLite, even Ruby!

Emscripten
https://github.com/kripken/emscripten/wiki

PlayN and Google Web Toolkit
https://developers.google.com/playn/
https://developers.google.com/web-toolkit/

PhoneGap
http://phonegap.com

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So
I’ve really only touched the tip of the iceberg here.
There is much more coming in the near future.
Here are a few ways to keep up with things and get yourself prepared, particularly the things
happening at Mozilla.

Are We Fun Yet?
https://wiki.mozilla.org/Platform/AreWeFunYet

Are We Mobile Yet? and B2G
http://arewemobileyet.com
https://developer.mozilla.org/en/Mozilla/Boot_to_Gecko

Firefox platform roadmap
https://wiki.mozilla.org/Platform/Roadmap

Firefox Aurora
“Get a first look at the latest developer tools, security features and innovative HTML5 and
other Web technologies.”
http://www.mozilla.org/en-US/firefox/channel/#aurora

Firefox Nightly
Bleeding edge functionality.
Testing only.
http://nightly.mozilla.org

Foundation HTML5 Canvas
Out now
Paperback and digital formats
Become a canvas master
Learn how to animate
Make two cool space games
RAWKES.COM/FOUNDATIONCANVAS
Foundation HTML5 Canvas is out now on Amazon and other reputable book stores.
http://rawkes.com/foundationcanvas

HTML5 Games Most Wanted
Out now
Paperback and digital formats
Learn from the best
Various game-related tutorials
Other tips and tricks
APRESS.COM/9781430239789
HTML5 Games Most Wanted is out now on Amazon and other reputable book stores.
http://apress.com/9781430239789

Rob Hawkes
@robhawkes
Rawkes.com
Personal website and blog
RECENT PROJECTS MORE COOL STUFF
Twitter sentiment analysis Rawket Scientist
Delving into your soul Technical Evangelist at Mozilla
Rawkets.com Slides
HTML5 & WebSockets game slideshare.net/robhawkes
Get in touch with me on Twitter: @robhawkes
Follow my blog (Rawkes) to keep up to date with stuff that I’m working on: http://
rawkes.com
I’ve recently worked on a project that analyses sentiment on Twitter: http://rawkes.com/
blog/2011/05/05/people-love-a-good-smooch-on-a-balcony
Rawkets is my multiplayer HTML5 and JavaScript game. Play it, it’s fun: http://rawkets.com
These slides are online at slideshare.net/robhawkes

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Thank you.
If you have any questions feel free to grab me, or bug me on Twitter (@robhawkes).
I’m a friendly chap and I’ll be happy to help.