Book Image

Game Development with Rust and WebAssembly

By : Eric Smith
Book Image

Game Development with Rust and WebAssembly

By: Eric Smith

Overview of this book

The Rust programming language has held the most-loved technology ranking on Stack Overflow for 6 years running, while JavaScript has been the most-used programming language for 9 years straight as it runs on every web browser. Now, thanks to WebAssembly (or Wasm), you can use the language you love on the platform that's everywhere. This book is an easy-to-follow reference to help you develop your own games, teaching you all about game development and how to create an endless runner from scratch. You'll begin by drawing simple graphics in the browser window, and then learn how to move the main character across the screen. You'll also create a game loop, a renderer, and more, all written entirely in Rust. After getting simple shapes onto the screen, you'll scale the challenge by adding sprites, sounds, and user input. As you advance, you'll discover how to implement a procedurally generated world. Finally, you'll learn how to keep your Rust code clean and organized so you can continue to implement new features and deploy your app on the web. By the end of this Rust programming book, you'll build a 2D game in Rust, deploy it to the web, and be confident enough to start building your own games.
Table of Contents (16 chapters)
1
Part 1: Getting Started with Rust, WebAssembly, and Game Development
4
Part 2: Writing Your Endless Runner
11
Part 3: Testing and Advanced Tricks

Refactoring for endless running

By now, you've properly noticed a pattern. Every time we add a new feature, we start by refactoring the old code to make it easier to add it. This is generally a good practice in most forms of software development, and we'll be following that same pattern now. We identified a couple of code smells while creating the infinite background, so let's clean those up now, starting with dealing with all those casts.

f32 versus i16

We had to cast values several times to go from i16 to f32 and back again. This isn't a safe operation; the maximum of f32 is orders of magnitude larger than the maximum of i16, so there's the potential for our program to crash on a big f32. HtmlImageElement uses u32 types, so all the casting to make the compiler shut up isn't even correct. We have two choices here:

  • Take our data types (such as Rect and Point) and make them match HtmlImageElement.
  • Set Rect and any other domain object to...