name: verify description: Build, launch, and drive mesh-studio headlessly to verify a change at the browser surface (WebGL renders fine under headless Chrome + SwiftShader).#

Verifying mesh-studio#

npm run build only gates TS + bundling. The real surface is the browser (OCCT WASM + three.js WebGL), and it works headlessly:

1. npm run dev -- --port 5199 --strictPort (background).

2. Drive with playwright-core (install it in the scratchpad, not the repo) using system Chrome — WebGL needs the SwiftShader flags:

   chromium.launch({
     executablePath: '/usr/bin/google-chrome',
     headless: true,
     args: ['--use-angle=swiftshader', '--enable-unsafe-swiftshader'],
   })
   

3. Cheapest end-to-end flow (no network): click the "Box" primitive button. That triggers the ~50 MB OCCT WASM load (local, a few seconds) — wait for .view-overlay to appear and .busy to disappear, then screenshot. "Random CAD model" additionally exercises the network import path.

Gotchas#

• Rendering is deterministic — byte-identical screenshots across runs means your change did NOT take effect, not that it's stable.
• To pixel-check the canvas, screenshot the .viewport canvas locator and analyze in-page via a 2D canvas; gl.readPixels returns blanks because the renderer doesn't preserve the drawing buffer.
• Face picking: click the canvas center and look for a sidebar h2 matching Face #.
• node_modules reads are permission-denied here; inspect library behavior at runtime (temporary console.log in app code + a page that captures console) instead of reading vendored source.