A small Next.js viewer for browsing and previewing Project Sekai Live2D models.

• Browse available models from a local asset server
• Load and preview Live2D models in the browser
• Play motions and facials
• Download the selected model as a ZIP
• Export motions into motions/*.motion3.json
• Capture screenshots from the viewer

• Next.js 16
• React 19
• PixiJS 8
• untitled-pixi-live2d-engine
• fflate

Install dependencies:

pnpm install

Start the development server:

pnpm dev

Build for production:

pnpm build

Start the production server:

pnpm start

The app reads the asset server URL from NEXT_PUBLIC_SERVER_URL.

If it is not set, it defaults to:

http://127.0.0.1:8080

Example:

NEXT_PUBLIC_SERVER_URL=http://127.0.0.1:8080 pnpm dev

When downloading a model as ZIP:

• the .model3.json file is placed at the ZIP root
• model assets are included with normalized relative paths
• motions are exported into motions/*.motion3.json
• the exported model3.json is rewritten to register those motions

This project depends on a compatible local model server that exposes:

• /model_list.json
• /model/<path>/<file>
• /motion/<path>/...