A 2D voxel / falling-sand engine for Unity 6 (URP). Burst-compiled cell solver, streamed infinite worlds, scriptable chemistry, smooth liquids/gases/fire, in-engine level editor, save/load, rigidbody bridge.

This document is the single source of truth for everything the engine can do, every public API surface, every extension point, and every limitation. Beginners can read top-to-bottom; advanced users can jump to the Extension Hooks and API Reference sections.

Table of Contents

1. What MatterForge Is — and Is Not
2. Requirements
3. Quickstart (30 seconds)
4. Core Concepts
5. The Profile — One Asset For Everything
6. MatterForgeWorld — Beginner API
7. Materials — Authoring and Built-ins
8. Reactions — Chemistry Rules
9. Structures and the Level Editor
10. PixelBodies — Rigidbody Bridge
11. World Generation
12. Persistence — Save and Load
13. Rendering and Visuals
14. Performance Tuning
15. Bounded vs. Infinite Worlds
16. Extension Hooks — Custom Passes