Introduction

This is a great book!

Now thats a pretty conceited opening line, so let me clarify. The books greatness has nothing to do with my writing ability, personality, or anything else about me . I consider it great because of the subjects it covers. This is the book Ive been looking for since 1999. If someone else had written it back then, I would have bought it, read it, called it a great book, and that would be the end of the story. But since nobody seemed to be stepping up to the task, I decided to do it myself .

Even the list of contents isnt my brilliant idea. Its the list of things I struggled to learn over the years , and the questions constantly asked on various Flash forums, in mailing lists, and in feedback from my personal site. In short, this is the stuff that I wanted to learn, and Im betting its the stuff you want to learn as well.

Let me also admit that very few of the techniques here are things I invented. They are the result of years of researching not only established formulas and methods, but also efficient ways of implementing these methods in Flash, given its special limitations and strengths. I cant even say that I had all of these answers when I started the book. A fair amount of research was done while writing, and I am a much wiser man than I was when I started.

You should keep a few things in mind as you read through this book. First, know that I try to avoid saying that any technique is the way or even the best way to do something. Ive found that as soon as you label something the coolest, best, fastest , and easiest way of doing something in Flash, someone is going to come out of the woodwork with a cooler , better, faster, and easier way. So, Ill just say that the techniques in the book will work, look good, and be relatively efficient in terms of CPU and memory use. But feel free to improve on them, and let me know when you do!

Second, you wont find a lot of start-to-finish , polished project tutorials here. Im not going to walk you through building a full-featured game with a splash screen, sound effects, and high-score table. I might show you how to move a spaceship around, like in the game Asteroids, and how to tell when its hit something. The rest is up to you. Publishers of books and magazines often seem to think that readers want a step-by-step description of how to build some specific project, down to the last detail. Thats great if you happen to want to build that exact project. But chances are you already have a pretty cool game, application, or other project in mind, and you just need to know how to build the various pieces and put them together. That is the knowledge that I strive to bring to you.

Finallyand Ill be repeating this one endlessly throughout the booka lot of the math and physics I present will have serious departures from a standard text on the same subject. I take a lot of shortcuts and a few out-and-out cheats, all in the name of a smooth-running movie. While you could, in theory, create a Flash movie that has almost perfectly accurate physics, you might wind up measuring its speed in seconds per frame rather than frames per second ! So, there are sacrifices and tradeoffs. In most cases Ill point out these departures. And in every case, a lot of effort and testing has gone into making sure that if it isnt exactly accurate, it at least looks like its accurate.

But enough warnings and disclaimers. This is a great book! Have fun with it. Make stuff you never dreamed you could make in Flash. Above all, use this book as a jumping-off point. Experiment, learn other subjects, and add the knowledge you gain to the examples given. I look forward to seeing what you come up with!