3dtours
e6c050581f
The AUTO chip measured the photo and wrote one knob, EV. It now writes the four
the measurement actually names, off the same binned ramp (ui/Histogram.tsx),
which is why it is one chip and not four: the means it needs are all in the
histogram the exposure answer already reads.
EV the mean luma, unchanged
HIGHLIGHT the top 1% (p99 > 0.9 pulls back), to -5 of the ruler at most
SHADOW the bottom 1% (p01 < 0.02 opens up), to +5
TEMPERATURE/TINT the gain that puts the three channel means on each other,
green as the anchor: gray-world on linearised means, then the
closest of 76 temperatures x 21 tints under the renderer's own
kelvinToRGB, so the pair cannot drift from what the ruler applies.
The ends rather than the average is what keeps a small blown window from
dragging the whole frame: a specular in the corner wants HIGHLIGHT, not a
flatter picture everywhere. Both ends stop at half the ruler, so the frame is
corrected and a hand can still finish the move; the knobs then report the
numbers AUTO chose, the way the EV knob does.
Each reading is a pure function of the ramp, so pressing AUTO twice lands on the
same recipe by construction, and a frame with a dead channel leaves the WB ruler
where it is rather than inventing a cast. ponytail: one linear ramp per end and
no scene analysis; add a curve, or weight by how much of the frame is clipped,
when AUTO starts overshooting a scene with a genuine specular in it.
scripts/auto-tone-check.mjs holds the three readings: the percentile walk, the
thresholds that leave a knob alone, and the scan landing back on the gain it was
asked for.
RecipesCam web — self-contained stack
A Docker-hosted web build of RecipesCam. Everything it needs is in this folder: move it to another machine, run two commands, and the app is up. It does not need the React Native project around it.
cp .env.example .env
docker compose up -d --build
# → http://localhost:8090
What runs where
| Service | Image | Role |
|---|---|---|
frontend |
nginx:1.27-alpine (built by frontend/Dockerfile) |
Static SPA + /api/ reverse proxy |
api |
node:22-slim (built by backend/Dockerfile) |
Accounts + saved recipes, SQLite on ./data |
frontend resolves api through Docker's embedded DNS and proxies /api/* to
it — that is why the API container is named api and why it is not published on
the host. Only ${WEB_PORT:-8090} is exposed.
Photos never leave the browser. The CanvasKit render pipeline (grade, frame, watermarks, JPEG encode) runs in the visitor's tab; the API only stores recipes as JSON.
Layout
docker-compose.yml the stack
.env.example WEB_PORT
data/ SQLite (created on first run, gitignored)
backend/ Fastify + better-sqlite3 API, own Dockerfile
frontend/ Vite + React + CanvasKit SPA, own Dockerfile + nginx.conf
shared/ vendored copies of the app's types + utils (see below)
src/engine/ skiaShim.ts (CanvasKit) + exportEngine.ts (render pipeline)
+ session.ts (localStorage/IndexedDB studio persistence)
Vendored files
frontend/shared/{types/index.ts,utils/*.ts} are byte-identical copies of
src/types/index.ts and ten src/utils/*.ts files from the React Native
project (@shopify/react-native-skia is aliased to src/engine/skiaShim.ts in
vite.config.ts + tsconfig.json, so those files compile unchanged):
cinemaShader colorUtils defaultRecipes exifWrite frameUtils jpegDpi
paramDefs recipeShare skiaImage toneShader.
The landing page needs no CDN: frontend/public/assets/fonts/*.woff2 are the
seven self-hosted faces behind the three font groups the Themes menu offers
(Plus Jakarta Sans / Inter / JetBrains Mono, Fraunces / Be Vietnam Pro /
Courier Prime, Be Vietnam Pro / Space Mono — all SIL OFL, pulled from Google
Fonts, vietnamese + latin + latin-ext subsets), and
frontend/public/assets/samples/s*.jpg are the six placeholder negatives the
film strip, preset tester and QR card show (swap them for real graded stills
whenever we have them). Its one foreign request is the QR image from
api.qrserver.com, which degrades to an empty slot offline.
When the app changes one of them, copy it back in — the renderer is only "parity" for as long as these stay in sync:
cd <repo>/docker/frontend/shared/utils
cp <repo>/src/utils/<name>.ts .
Operations
docker compose logs -f api # API log
docker compose restart api # after backend/src changes (rebuild: --build)
docker compose down # stop; ./data survives
Backup is the ./data folder — that is the whole database.
Checks
curl -s http://localhost:8090/api/health # {"ok":true}
curl -sI http://localhost:8090/ # 200, index.html
Then open the UI, drop a photo in, and confirm the preview shows the picture and
EXPORT downloads a JPEG that opens. The preview going solid black while the
export still reports a plausible size is the one failure mode worth knowing: it
means the CanvasKit GPU surfaces lost their shared GrDirectContext (see
frontend/src/engine/skiaShim.ts), and with no GPU the raster fallback renders
the same pipeline correctly, just slower.