SpritePacker

SpritePacker is a browser-only sprite sheet slicer built with Next.js. Drop in a sheet (or multiple images), auto-detect sprites, tweak boxes, repack to a new atlas, and export individual sprites or an atlas+JSON without sending assets to a server.

Features

• Auto-detect sprites via alpha / color-key / adaptive background detection
• Repacking with spacing, fixed-size atlases, and multiple packing heuristics
• Export to PNG/JPEG/WebP sprites or atlas bundles with common JSON formats (Pixi/Phaser/etc.)
• Light/Dark theme toggle and configurable checkerboard backgrounds
• 100% client-side; no uploads are persisted

Planned Improvements

The following enhancements are planned to make SpritePacker more powerful, reliable, and user-friendly:

1. Increase Test Coverage

   • Add unit tests for core image processing, detection, and packing logic
   • Introduce integration tests for end-to-end workflows
   • Establish automated CI testing to ensure long-term stability

2. Support Additional Export Formats

   • Implement multiple atlas schemas (Unity, Godot, Cocos, Spine, etc.)

3. Expand and Improve Documentation

   • Create detailed user guides and tutorials

4. Enhance Packing Algorithms

   • Implement additional packing strategies (MaxRects, Guillotine, Shelf, etc.)
   • Improve efficiency and atlas space utilization

5. “Detect Identical Sprites” Feature

   • Identify duplicate or visually identical images
   • Automatically merge them to reduce atlas size

6. Localization Support

   • Add multi-language interface support

Quick Start

1. Ensure Node 20+ is installed.
2. Install dependencies:

   npm install

3. Run the app locally:

   npm run dev

   The app will be available at http://localhost:3000.
4. Build for production:

   npm run build
   npm start

License

MIT License. See LICENSE for details.