3dtours
0e9f78bd5e
MONOCHROME GRAIN was one integer knob 0..10 with one meaning, how much. It is now
a strip of three: AMOUNT — the same knob, in half steps — SIZE, a percentage of
the stock's own grain cell (50..200%, so the same number means the same texture
relative to the picture on both platforms), and an inert readout of N/INCH, the
clump count the two knobs and the stock add up to in the print's own terms (300
dpi = 300px of the 1080-wide reference the knob was tuned at).
Emulsion is not one grain size across the frame: the coating settles unevenly.
The field now prints that — the same hash read slowly (ZONE_FREQ = 1/96 cells,
turned off the axes, smoothed so a border between two patches is a slope and not
a seam) swings each patch's own cell by half of ZONE_SWING either way, ±20%.
Nothing in it moves the field's mean: a coarser patch prints bigger clumps, not a
brighter one, which is why the strip can read out one number while the frame
carries a range.
A patch may not swing a cell under the pixel the target can print, or the clumps
are sub-pixel and print as static — aliasing, not a finer emulsion. The shader
takes that floor as a `mincell` uniform beside the cell (u, mincell, seed.xy, in
declaration order): an export passes one output pixel, a preview one device pixel
(1 / PixelRatio), which is the floor the phone's preview already needed.
SIZE is stored as an integer percent so no float noise reaches the recipe JSON,
and it is read by the same two engines that read grain: the web's
grainCell(width, stock, sizePct) and the phone's grainCell(width, minCell,
sizePct). The chip above the strip carries the amount in half steps the way TEMP
carries the kelvin, and the readout moves with SIZE, not with AMOUNT.
Measured:
grain-controls-test.cjs 20/0 — the strip carries grp-grain, grain:amount,
grain:size and grain-inch; the AMOUNT ruler is 0..10 step 0.5, and 3 -> 3.5
moves the frame (sigma 18.53 -> 21.91, new hash) without moving the readout;
10 -> sigma 60.43, 0 -> sigma 0; SIZE 200% -> 130/INCH (sigma 40.06), 50% ->
522/INCH (66.56: under the preview's pixel floor what is printed is static,
not finer grain); the region claim on an 8x8 grid of the flat frame gives
tile sd 51.0..66.1, max/min 1.295, and a tile mean spread of 1.14 — a coarser
patch is not a brighter one.
grain-size-test.cjs 17/0 (was 12/0) — the SIZE rule and the readout on the
module itself: 200% doubles the cell, 50% halves it, the output pixel still
floors the smaller one. 4000px file cell 3.704 against 1.083 device px on a 3x
preview, the old one-dp floor 2.77x coarser, rho1 0.627 against 0.074. The
harness built its own 3-uniform array; it now passes [u, mincell, seed.xy]
like every other caller.
_grain-zone-ck.cjs — the zone's own contribution, at preview scale (cell 1.70,
1600px, 8x8 tiles of 200px): zone on, tile sd 23.22..24.82 (ratio 1.069);
zone off, 24.42..24.79 (ratio 1.015). Nothing else differs.
_grain-ck.cjs — the clump field is otherwise what it was: rho1 0.62
classic-neg / 0.12 velvia, residual autocorr 0.035 against 0.036 with the
swing forced to 0, peak/median 32.3 against 27.6.
_grain-spectrum.cjs (app, 1600px render) — residual autocorr 0.017..0.018,
spectral peak/median 4.6..6.1: the slow lattice adds no peak of its own.
grain-stock-test 53/0, sims-test 31/0, fx-mono-test 15/0, wb-preset-test 33/0,
temp-swatch-test 33/0, wm-font-test 38/0, grain-analog-test 7/0 (its grain
selectors moved to the strip).
tsc: web clean; the phone's scoped config reports exactly the pre-change
baseline (Viewfinder.tsx's own errors, none new).
ponytail: the amount is fractional now, so the two recipe-create forms read grain
through their own half() instead of the int() that would truncate the half the
ruler just spent — every other knob there is still whole. The SIZE knob is one
number for the whole strip: no way to dial a single patch, and no seed control.
The readout is the DESIGN count the field is built on, never a per-patch
measurement.
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.