vectorcraft/docs/development.md

Development

Web build

apps/vectorcraft-web runs the same VectorcraftApp in the browser through eframe's web runner. The renderer is wgpu: WebGPU where the browser has it, WebGL2 otherwise. It is Rust only; the only JavaScript is the glue wasm-bindgen generates.

brew install trunk                 # or: cargo install trunk --locked
rustup target add wasm32-unknown-unknown
cd apps/vectorcraft-web
trunk build --release              # writes ../../dist/web (index.html, .js glue, .wasm)
trunk serve --release              # dev server on http://127.0.0.1:8766

Any static file server works for dist/web, for example python3 -m http.server 8766 inside that directory. The release .wasm is about 17.5 MB, or 7.1 MB gzipped, so serve it with compression.

URL flag: ?webgl forces the WebGL2 backend.

How the web shell (apps/vectorcraft-web/src/web.rs) differs from desktop:

• Open sets Services::open_async, which shows rfd::AsyncFileDialog. The bytes arrive in Services::inbox, which the app drains every frame.
• Save / Save As / Export go through Services::download: a Blob, an object URL and a temporary <a download>, all created from Rust. There is no save dialog, so the suggested name becomes the download name.
• Drag-and-drop: WebShell takes the frame's dropped_files before the app sees them, reads each with DroppedFile::bytes_async and pushes the bytes into the inbox. (The app's synchronous drop path is compiled out on wasm32.)
• No control server: browsers can't listen on TCP. To automate the web build, drive headless Chrome with --remote-debugging-port.
• Quick smoke test: "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome" --headless=new --enable-unsafe-webgpu --screenshot=web.png --window-size=1440,900 --virtual-time-budget=15000 http://127.0.0.1:8766/ (headless Chrome on macOS gets a real WebGPU adapter).