Minecraft World Viewer

A web app that converts Minecraft world .zip files into interactive 3D models in your browser.
Built with Next.js + Three.js, deployable to Vercel in one click.

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Features

• Upload any Minecraft Java Edition world .zip (1.9–1.20)
• Parses Anvil .mca region files directly in the browser (no server needed)
• Block-accurate color rendering with 150+ block types
• Interactive 3D camera (drag to rotate, scroll to zoom)
• Handles up to 500,000 blocks with instanced rendering
• Mobile-friendly touch controls
• Adjustable Y-range filter to focus on specific layers

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Local Development

npm install
npm run dev
# Open http://localhost:3000

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Project Structure

minecraft-viewer/
├── pages/
│   ├── index.js          # Main app page
│   └── _app.js
├── components/
│   └── MinecraftViewer.js  # Three.js 3D renderer
├── lib/
│   ├── mcaParser.js      # Minecraft Anvil .mca parser
│   ├── nbtParser.js      # Binary NBT parser
│   └── blockColors.js    # Block → color mapping (150+ blocks)
├── styles/
│   └── globals.css
├── next.config.js
├── vercel.json
└── package.json

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How It Works

1. Upload — You select a Minecraft world .zip file
2. Extract — JSZip reads the archive in the browser
3. Parse MCA — Each .mca region file is parsed using the Anvil format spec
4. Parse NBT — Chunk NBT data is decoded to extract block palettes and block state arrays
5. Render — Three.js InstancedMesh renders blocks with accurate colors and lighting

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Supported Formats

• Minecraft Java Edition 1.16+ (Anvil format, 1.16 chunk format)
• World .zip files exported from the game's "Open World Folder" feature

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Performance Tips

• Use the Y Range filter to limit to the layer containing your structure
  (castles are usually Y 60–130, underground builds Y 0–60)
• The viewer automatically limits to 500k blocks and prioritizes structural blocks
• On slower devices, smaller worlds will render faster