# Yawn

Yawn Core is two things: a generic structure-of-arrays arena in a `SharedArrayBuffer`, and a Rust render graph that turns externally supplied WGSL into an up-front WebGPU loadout.

```text
JSO or FXNode → AST → S-expression → worker messages → Rust/WebGPU
                                                   ↑
any thread → direct shared row writes ─────────────┘
```

The arena starts with only one eight-float `signals` row for frame timing and render invalidation. Messages create or delete other `{ name, rows, stride, format }` arrays, allocate named slots, compile graphs, switch loadouts, and control render pacing. Existing render data is changed by writing `f32`, `u32`, or `i32` rows directly, then setting the shared-data dirty signal. Allocations are 64-byte aligned, row strides are multiples of 16 bytes, and compatible non-overlapping transient textures share physical allocations.

WGSL, pipelines, glTF import, and conventional mesh/camera/material handles live in `addons/`; core contains no shader or scene model.

Run the Go website, in-memory package server, SQLite-backed playground, and tutorial:

```sh
npm run server
```

The server rebuilds `@yawn/core` and `@yawn/handles` at startup and serves the public CDN modules at
`https://yawn.heaust.org/pkg/core.js` and `https://yawn.heaust.org/pkg/handles.js`. Handles keeps Core
as a separate module dependency instead of bundling it. Map and import both URLs as shown in
`server/examples/basic.html`; their workers and WASM stay on the CDN automatically. The complete editor is at `/playground`; saved revisions use
`/playground/{id}/{revision}` URLs. Set `PORT` or `YAWN_DATABASE` to override the default port and
`server/data/yawn.db` database path.

## VPS deployment

Clone the repository to `~/yawn` on a VPS with Docker and the Compose plugin, then run:

```sh
cd ~/yawn
./server/deploy-docker.sh
```

The deploy script requires a clean `main`, fast-forwards it to `origin/main`, builds the production
image, starts it with Docker Compose, and waits for the health check. Core, Handles, workers, and
WASM are compiled while building the image; the runtime container only holds the Go server,
prebuilt package assets, Monaco, and the persistent SQLite volume. Configure the port and database
path in `compose.yaml`. The default port binding is private to the VPS at `127.0.0.1:5002`; put
Caddy or nginx in front of it for HTTPS. Follow logs with `docker compose logs -f yawn`.

Run the previous VitePress documentation site with `npm start`.

Run `npm run coredocs` for the raw worker-message, shared-memory, and render-graph reference intended for custom handles, editors, and direct SAB clients.