Book Image

Game Development Patterns and Best Practices

By : John P. Doran, Matt Casanova
Book Image

Game Development Patterns and Best Practices

By: John P. Doran, Matt Casanova

Overview of this book

You’ve learned how to program, and you’ve probably created some simple games at some point, but now you want to build larger projects and find out how to resolve your problems. So instead of a coder, you might now want to think like a game developer or software engineer. To organize your code well, you need certain tools to do so, and that’s what this book is all about. You will learn techniques to code quickly and correctly, while ensuring your code is modular and easily understandable. To begin, we will start with the core game programming patterns, but not the usual way. We will take the use case strategy with this book. We will take an AAA standard game and show you the hurdles at multiple stages of development. Similarly, various use cases are used to showcase other patterns such as the adapter pattern, prototype pattern, flyweight pattern, and observer pattern. Lastly, we’ll go over some tips and tricks on how to refactor your code to remove common code smells and make it easier for others to work with you. By the end of the book you will be proficient in using the most popular and frequently used patterns with the best practices.
Table of Contents (19 chapters)
Title Page
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
4
Artificial Intelligence Using the State Pattern

Separating the why and the how


When creating games, we have many different systems that need to be juggled around in order to provide the entire game experience. We need to have objects that are drawn to the screen, need to have realistic physics, react when they hit each other, animate, have gameplay behavior and, on top of all that, we then need to make sure that it runs well 60 times every second.

Understanding the separation of concerns

Each of these different aspects is a problem of its own, and trying to solve all of these issues at once would be quite a headache. One of the most important concepts to learn as a developer is the idea of compartmentalizing problems, and breaking them apart into simpler and simpler pieces until they're all manageable. In computer science, there is a design principle known as the separation of concerns which deals with this issue. In this aspect, a concern would be something that will change the code of a program. Keeping this in mind, we would separate each of these concerns into their own distinct sections, with as little overlap in functionality as possible. Alternatively, we can make it so that each section solves a separate concern.

Now when we mention concerns, they are a distinct feature or a distinct section. Keeping that in mind, it can either be something as high level as an entire class or as low level as a function. By breaking apart these concerns into self-contained pieces that can work entirely on their own, we gain some distinct advantages. By separating each system and making it so they do not depend on each other, we can alter or extend any part of our project with minimal hassle. This concept creates the basis for almost every single design pattern that we'll be discussing.

By using this separation effectively, we can create code that is flexible, modular, and easy to understand. It'll also allow us to build the project in a much more iterative way because each class and function has its own clearly defined purpose. We won't have to worry nearly as much about adding new features that would break previously written code because the dependencies are on the existing functional classes, and never the other way around. This means we can to easily expand the game with things like Downloadable Content (DLC). This might include new game types, additional players, or new enemies with their own unique artificial intelligence. Finally, we can take things we've already written and decouple them from the engine so we can use them for future projects, saving time and development costs.