The FRAME tab's fine rotation drew the photo through canvas.rotate() +
canvas.scale() with a plain drawImage, which CanvasKit samples with
nearest: the edge landed on the same pixel in every row, so a rotated
edge came out as 1px steps every 1/tan(angle) rows. Measured on the 30deg
export of a hard black/white edge: 42.3% of rows repeated the previous
row's edge position, the step across the edge was 252.9 of 255, and there
were no intermediate pixels at all.
Only the *Options/*Cubic call shapes take a sampling option, and
drawImageRectOptions exists in RN Skia too, so the shared renderer can use
it unchanged. The same export now moves the edge in every row (0.2% of
rows repeat, 0.35 intermediate pixels per row) and its edge step drops to
222. Cost: the filtered draw takes 0.35s against 0.24s for the 1600px
preview copy and 2.0s against 1.4s for a 12MP photo, once per render.
Preview and export share the function, so both change together.
`docker/` now holds the whole web build — frontend (Vite + React + CanvasKit),
backend (Fastify + SQLite) and the compose file — so the folder can be moved to
another machine and run without the React Native project:
cd docker && cp .env.example .env && docker compose up -d --build
Only `${WEB_PORT:-8090}` is published; nginx serves the SPA and proxies /api to
the `api` container over Docker's DNS. Photos never reach the server.
The shared render code is vendored into `docker/frontend/shared/` and aliased to
a CanvasKit shim, so the app's own frameUtils/toneShader/jpegDpi run unchanged.
Fix the all-black render on GPU surfaces: `MakeWebGLCanvasSurface` creates a
separate WebGL context per call, and a texture from one context cannot be
sampled by a surface on another — so any pass that drew a snapshot onto a second
surface (output sharpen, screen sharpen, polaroid/wallframe cards) came out
solid black, while the raster fallback was correct. Use one shared
GrDirectContext + MakeRenderTarget instead.
Verified in headless Chromium against the running stack: 12MP JPEG in, preview
mean=120.5 sd=60.5, export 2048x1536 mean=107.2 sd=62.1, JFIF density 300/300,
EXIF present, no console errors; health/signup/login/me/recipes all 2xx through
the nginx proxy.
3dtours