AI for Game Developers

Rating:
Summary: Very good
Review: I found AI for Game Developers to be a great introduction to many AI techniques in the context of computer games. The book is well written, concise (as are all O'Reilly books), and easy to read. It remains accessible to novices by staying away from ostentatious academic lingo and presents the material in clear English with many code examples to back up the text (every chapter has at least one code example implementing the technique being discussed).

One of the really nice things about this book is that it presents different approaches to accomplishing the same thing. For example, chasing, evading and obstacle avoidance is demonstrated using steering algorithms, line of sight and interception techniques, as well as potential functions. The authors also show how to handle strike prediction for fighting games using two different techniques - rules versus statistical. This gives a comparison of the strengths and weaknesses of each technique.

Further, the book introduces more advanced algorithms like fuzzy rules systems, Bayesian decision making, neural networks, and genetic algorithms in very clear language with solid code examples. In fact, based on this book I'm using the genetic algorithm and neural network approaches to model adaptive creatures in a role playing game that I'm working on.

All in all, this book is accessible and useful.


Rating:
Summary: Excellent algorithm text even for non-game developers
Review: I'm not a game developer by trade but I still found an excellent introduction to some interesting algorithms in this book. For me these included an introduction to neural networks (at the end of the book), probability theory, and finite state machines. I've read (and looked over) a number of books on game development and they, in general, seem to prattle on about the games themselves, or spend an inordinate amount of time on the graphics or the presentation. That stuff is important, but at the heart of these systems are algorithms animate the game and bring it to life. This book concentrates on those algorithms by expressly playing down the graphics elements.

I can safely recommend browsing this book to almost any software engineer. You may find some stuff that interests you and you can use even if you aren't a game developer.

Rating:
Summary: Simple explanations of major ideas
Review: In games, developers often concentrate on improving the graphics, because this is the first thing that catches people's attention. But suppose you've done that successfully. Beautiful, fast rendered, high resolution images. How then do you KEEP the player's attention? Especially vis-a-vis other games.

So there is intense pressure on you, the developer, to make your characters more sophisticated. Bourg and Seemann offer help. The title says AI, but this can be intimidating to some. You can instead consider this as an algorithms book, that eases you gently into what can be topics of astonishing depth. Many important ideas are covered, like cellular automata and artificial life flocking. (Surprisingly, Conway's Game of Life isn't cited.) From physics, we see the use of potential functions to control character movement. We get simple explanations of finite state machines, fuzzy logic, neural networks and genetic algorithms.

The virtue of this book is that the topics are understandable to developers. Hitherto, using those ideas would have required you to be a specialist in the fields. Crucially, there are code snippets that illustrate the core concepts of each major idea. Sounds like a trite statment perhaps. But if you have ever cracked open a monograph on fuzzy logic, say, and then tried to go from it to writing code, you'll understand the usefulness of what this O'Reilly book offers.

Rating:
Summary: No, no, no!
Review: Oh dear. This is a really poor book, and I'd advise you to save your money and buy something else.

Bourg's first book on game development (on Phyiscs) suffered poor reviews for being shallow, not presenting real-world techniques, and glossing over huge gaping problems in his approach. This book has all the same problems, and even more strongly in places.

Firstly he makes a big point of saying that the book is aimed at novice developers and he will cover only a few techniques designed to get you up and running. In his list, however, he has genetic algorithms, neural networks and production systems, all of which large AI teams for major developers find it very hard to get working usefully (e.g. finding an application suited for a GA in a game is just about impossible). His approaches are in places laughable.

Secondly he then lauds completely inappropriate algorithms. His steering system is based on potential functions, for example, and he proposes this because he says it allows you to mix several different movement concerns. This is completely disingenuous to his readers. The technique is very simple and useful only when several concerns are NOT blended together. When you mix things you ALWAYS get wells-of-attraction and your characters get stuck hopelessly. Just about ANY other technique would improve on this (and there's no use just saying 'do pathfinding' either: there's much more mileage in steering algorithms).

And the final thing that annoyed me was his approach all the way along of saying 'I'm only going to show you a few techniques'. Trying to make the selling point of the book that it doesn't cover anywhere near enough ground to get your AI up and running!

Just about every chapter had significant problems in it. His knowledge of the subject wouldn't pass a sophomore AI exam (I've taught AI courses at University: I'm not exaggerating). It is full of innaccuracies (e.g. he says 'new AI' is non-deterministic, while 'old AI' is deterministic - a moronic comment).

If you are a novice trying to get going in AI, this book will seriously harm you development. Try John Funge's new book, or the new Morgan Kauffman book (you'll have to wait a few months). Even reaching through the two AI Programming Wisdom will see you far better prepared for real development, despite the odd lemon of an article in them.