Preface

Writing games is not only fun but also a very good way to learn a technology through and through. Even though HTML and JavaScript weren't conceived to run games, over the last few years, a series of events have occurred to make writing games in JavaScript a viable solution:

• Performance of browsers' JavaScript engines has improved dramatically, with modern engines being ten times faster than the state of the art engines in 2008

• jQuery and other similar libraries made working with the DOM as painless as it can be

• Flash lost a lot of ground due, in part, to its absence on iOS

• W3C started work on many game-oriented APIs such as canvas, WebGL, and full-screen APIs

Throughout this book, you will make three games and learn a wide array of techniques. You will not only be able to use your own games, but most importantly you will have fun doing so!

What this book covers

Chapter 1, jQuery for Games, provides an in-depth look at jQuery's functions that might be useful for game development.

Chapter 2, Creating Our First Game, implements a simple game with sprites, animation, and preloading.

Chapter 3, Better, Faster, but not Harder, optimizes the game we saw in Chapter 2, Creating Our First Game, with various techniques such as time-out inlining, keyboard polling, and HTML fragments.

Chapter 4, Looking Sideways, codes a platformer game with tile maps and collision detection.

Chapter 5, Putting Things into Perspective, creates an orthogonal RPG with tile map optimization, sprite occlusion, and better collision detection.

Chapter 6, Adding Levels to Your Games, expands the game we saw in Chapter 4, Looking Sideways, by adding multiple levels using JSON and AJAX.

Chapter 7, Making a Multiplayer Game, transforms the games we saw in Chapter 5, Putting Things into Perspective, to support multiple players on multiple machines.

Chapter 8, Let's Get Social, integrates the platform game with Facebook and Twitter as well as creating a cheat-proof leaderboard.

Chapter 9, Making Your Game Mobile, optimizes the games we saw in Chapter 5, Putting Things into Perspective, for mobile devices and touch control.

Chapter 10, Making Some Noise, adds sound effects and music to your game with the audio element, the Web Audio API, or Flash.

What you need for this book

One of the advantages of working with web technologies is that you won't need any complex or costly software to get you started. For strictly client-side games, you will only need your favorite code editor (or even a simple text editor, if you don't mind working without any syntax highlighting). If you haven't chosen any yet, there is plenty of free software around you that you could try, ranging from very old-school, such as VIM (http://www.vim.org/) and Emacs (http://www.gnu.org/software/emacs/) to more modern, such as Eclipse (http://www.eclipse.org/) and Aptana (http://www.aptana.com/), Notepad++ (http://notepad-plus-plus.org/), or Komodo Edit (http://www.activestate.com/komodo-edit). These are only some of the available editors that you can find. For JavaScript, you don't need a very advanced editor, so just use the one you're more familiar with.

If you create you own graphic, you will also need an image editing software. Here again, you will have a lot of choice. The most famous open source software being Gimp (http://www.gimp.org/) and one of my personal favorites, Pixen (http://pixenapp.com/).

For the part of the book that needs some server-side scripts, we will use PHP and MySQL. If you don't already have a server that supports them, to install these on your machine, you can use MAMP (http://www.mamp.info/), XAMPP (http://www.apachefriends.org/en/xampp.html), or EasyPHP (http://www.easyphp.org/) depending upon your OS.

Who this book is for

The primary audience for this book is a beginner web developer with some experience in JavaScript and jQuery. Since the server-side part is implemented in PHP, it will help if you have some knowledge of it too, but if you're more comfortable with another server-side language, you could use it instead of PHP without too much trouble.

You won't need any prior knowledge of game development at all to enjoy this book!

Conventions

In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.

Code words in text are shown as follows: "The .animate() function from jQuery allows you to make a property vary through time from the current value to a new one."

A block of code is set as follows:

$("#myElementId")
.animate({top: 200})
.animate({left: 200})
.dequeue();

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

gf.keyboard = [];
// keyboard state handler
 $(document).keydown(function(event){
    gf.keyboard[event.keyCode] = true;
});
$(document).keyup(function(event){
    gf.keyboard[event.keyCode] = false;
});

Any command-line input or output is written as follows:

# cp /usr/src/asterisk-addons/configs/cdr_mysql.conf.sample
     /etc/asterisk/cdr_mysql.conf

New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: "The following figure shows what a typical one-dimensional intersection i of two segments a and b would look like".

Note

Warnings or important notes appear in a box like this.

Tip

Tips and tricks appear like this.

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