Introduction to LibGDX

What is LibGDX?

LibGDX is an open-source, cross-platform Java framework for game development. It provides a single unified API that lets you write your game once and deploy it to multiple platforms: desktop (Windows/Mac/Linux), Android, iOS, and HTML5 (WebGL via GWT). LibGDX handles low-level details like rendering, input, audio, asset management and platform integration so you can focus on game design and logic.

Why choose LibGDX for game development?

• Cross-platform from a single codebase: Write in Java and reuse most of the code across desktop, mobile and web.
• Lightweight & flexible: Not an engine that imposes a specific architecture — pick your patterns (Entity Component System, Scene2D, etc.).
• Good performance: Uses OpenGL (and WebGL for HTML5) for efficient rendering and gives access to low-level graphics when needed.
• Rich feature set: Built-in support for rendering (SpriteBatch, shapes), audio, input, file I/O, Box2D physics, particle effects, and UI (Scene2D.UI).
• Large community & resources: Extensive examples, tutorials, and third-party libraries/plugins to speed up development.
• Java ecosystem: Leverage familiar Java tools (Gradle, IDEs like IntelliJ/Android Studio) and libraries.

Supported platforms

LibGDX targets these main platforms with the same core code:

• Desktop: Windows, macOS and Linux (runs as a JVM application)
• Android: Native Android apps (APK/AAB)
• iOS: Uses RoboVM/alternative backends to produce native iOS apps
• HTML5 (Web): Compiles to JavaScript/WebGL using GWT so games run in the browser

Note: Platform backends and build tool specifics can change over time (tooling for iOS, for example), but the core principle remains: one codebase, multiple targets.

Setting up your development environment

Below are the typical steps to get started quickly. The recommended workflow uses the LibGDX setup tool which scaffolds a multi-module Gradle project.

1. Install Java JDK: Install a recent JDK (LTS or newer is fine). Ensure java and javac are on your PATH.
2. Install an IDE: Use IntelliJ IDEA (Community or Ultimate) or Android Studio. These provide excellent Gradle integration and debugging support.
3. Use the LibGDX setup tool: The setup tool generates a Gradle project with a core module and platform-specific modules (desktop, android, ios, html). You can configure project name, package, game class and desired extensions (Box2D, Ashley ECS, etc.).
4. Import the project: Open the generated Gradle project in your IDE and allow it to sync dependencies. The core module contains platform-independent game code.
5. Run the desktop launcher: The fastest way to iterate is to run the desktop backend from your IDE. It launches a JVM app window and reloads quickly during development.

Minimal example — a basic ApplicationListener

Place this in your core module as the main game class to see a simple render loop:

public class MyGame implements com.badlogic.gdx.ApplicationListener {
    private com.badlogic.gdx.graphics.g2d.SpriteBatch batch;
    private com.badlogic.gdx.graphics.Texture img;

```
@Override
public void create() {
  batch = new com.badlogic.gdx.graphics.g2d.SpriteBatch();
  img = new com.badlogic.gdx.graphics.Texture("badlogic.jpg");
}

@Override
public void render() {
  com.badlogic.gdx.Gdx.gl.glClearColor(0, 0, 0, 1);
  com.badlogic.gdx.Gdx.gl.glClear(com.badlogic.gdx.graphics.GL20.GL_COLOR_BUFFER_BIT);
  batch.begin();
  batch.draw(img, 10, 10);
  batch.end();
}

@Override public void resize(int w, int h) {}
@Override public void pause() {}
@Override public void resume() {}
@Override public void dispose() {
  batch.dispose();
  img.dispose();
}
```

}

What to read or try next

• Run the generated desktop launcher and confirm the default sample runs.
• Explore the core/src folder — that's your portable game logic.
• Try rendering a shape or sprite, and respond to a key press or touch event.

Ready for the next article? The next post will cover Project Setup & Structure in depth: using the setup tool, Gradle modules, project layout, and tips for organizing assets and code.