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

Moving Red Hat Boy

Moving game objects means keeping track of a position instead of hardcoding it, as you might have expected. We'll create a Point structure in engine that will hold an x and a y position for RHB. On every update call, we'll also calculate a velocity for him, based on which keys are pressed. Every direction will be the same size, so if ArrowLeft and ArrowRight are pressed at the same time, he'll stop moving. After we calculate his velocity, we'll update his position with that number. That should be enough to allow us to move him around the screen. Let's start by adding position to the WalkTheDog game struct:

pub struct WalkTheDog {
    image: Option<HtmlImageElement>,
    sheet: Option<Sheet>,
    frame: u8,
    position: Point,
}

Of course, Point doesn't exist yet, so we'll create it in engine:

#[derive(Clone, Copy)]
pub struct Point...