melonJS — Modern Lightweight HTML5 Game Engine

Introduction

melonJS is a lightweight, open-source HTML5 game engine that has been actively developed since 2011. It focuses on 2D game development for the browser with native Tiled map integration, making it straightforward to go from level design to playable game.

What melonJS Does

• Renders 2D games using WebGL2 with automatic Canvas fallback
• Loads and renders Tiled (.tmx) maps directly with collision layers and object parsing
• Provides entity-component system with built-in physics, collision detection, and input handling
• Supports sprite animations, bitmap fonts, particle effects, and tweening
• Includes an asset preloader with progress tracking for images, audio, JSON, and binary data

Architecture Overview

melonJS is written in modern JavaScript (ES modules) with a WebGL2 compositor at its core. The game loop runs via requestAnimationFrame with fixed-timestep updates and variable rendering. The world is organized into containers holding renderable entities sorted by z-index. Collision detection uses spatial hashing for broadphase and SAT (Separating Axis Theorem) for narrowphase resolution.

Self-Hosting & Configuration

• Install via npm and import as ES modules; works with any bundler (Vite, Webpack, Rollup)
• Alternatively use the UMD bundle via CDN for quick prototyping without a build step
• Game settings (resolution, scaling mode, physics gravity) are configured at initialization
• Tiled maps are loaded as-is; collision shapes are defined in object layers with type annotations
• Audio supports Web Audio API with fallback; formats recommended: ogg, mp3, wav

Key Features

• First-class Tiled integration: orthogonal, isometric, and hexagonal maps with animated tiles
• Responsive scaling modes: fit, fill, stretch, and flex for any screen size
• WebGL2 batch renderer with texture atlas support for minimal draw calls
• Plugin architecture for extending the engine (e.g., debug panel, spine runtime)
• TypeScript definitions included for type-safe development

Comparison with Similar Tools

• Phaser — larger community and plugin ecosystem; melonJS is lighter and more Tiled-native
• PixiJS — rendering library only; melonJS is a complete game framework with physics and input
• Kaboom/Kaplay — beginner-friendly scripting style; melonJS has more structured ECS architecture
• PlayCanvas — 3D-focused with web editor; melonJS is 2D-only and code-first
• Flame — Flutter/Dart ecosystem; melonJS is pure JavaScript for browser deployment

FAQ

Q: Can melonJS games run on mobile browsers? A: Yes. Touch input and responsive scaling work out of the box; games run on modern mobile browsers.

Q: Does melonJS support multiplayer? A: Not built-in, but you can integrate WebSocket or WebRTC libraries alongside the game loop.

Q: How does Tiled integration work? A: Export your Tiled map as JSON, load it with me.loader, and add it to the world. Collision shapes from object layers become physics bodies automatically.

Q: Is melonJS suitable for commercial games? A: Yes. It is MIT licensed and has been used in published HTML5 games distributed on web portals and app stores via wrappers.

Sources

• https://github.com/melonjs/melonJS
• https://melonjs.org