Commit Graph
3 Commits
Author SHA1 Message Date
dtourolleandClaude Opus 5 0233df4bf2 See what the highlights are doing: a live histogram (FR-DSP-7)
Exposure, blacks and whites were set by eye. Nothing said a highlight had
blown — the canvas shows white where a channel is at 250 and white where it is
at 255, and the difference is the whole question.

**Counted on the GPU, not on the readback.** There is a full frame sitting in
CPU memory on every canvas update right now — `AdjustPass::read_output`, the
bridge spike S1 removes — and walking it would have been thirty lines and no
shader. FR-DSP-7 states the mechanism and not just the feature: "these derive
from a GPU-side reduction into a small buffer. Per-frame CPU readback of image
data is prohibited." A histogram founded on the bridge would be correct today
and deleted by S1, and would meanwhile be the reason the bridge could not go.
What crosses the bus here is 4104 bytes whatever the image size.

The reduction tallies into workgroup memory first and merges once per
workgroup. A photograph is not noise: a clear sky puts tens of thousands of
adjacent pixels in one bin, and contending for that single global atomic
serialises the dispatch.

**On the settled frame only.** `render_now` already knows whether a gesture is
still moving — `draft` is the flag `redraw` derives from `was_coalesced` — so
the dispatch and its transfer happen once when the slider stops rather than on
each of the forty frames a drag emits. Nothing is lost: a histogram flickering
past under a finger is not a reading anyone takes. FR-DSP-7 requires exactly
this, that it not extend the FR-DSP-3 frame budget.

Luma is weighted in 8.8 fixed point — 54, 183, 19, summing to 256 exactly —
rather than in floats. Not thrift: it makes the shader's arithmetic
reproducible bit for bit, which is what lets the test below be an `assert_eq`
against a CPU count rather than a tolerance. ARCH §6.13's line about integer
state, applied where it happens to also be free.

**What the numbers were checked against.** A flat frame must put all 4096
pixels in one bin and one only. A 256-wide ramp must occupy every level with
exactly the same count, which is what catches an off-by-one in the
quantisation — a `floor` where a rounding was needed shifts the whole
photograph one bin left and looks like nothing at all. And a 101x37 frame of
seeded pseudo-random pixels — deliberately not a multiple of the 16x16
workgroup, so the edge tiles run off the image — is compared slot for slot
against a second, obvious CPU implementation. Exact equality, no tolerance.
The CPU version is a deliberate reimplementation rather than shared code: the
bugs worth catching here are ones shared code would commit identically on both
sides.

Above that, the presentation arithmetic is unit-tested headless, because it is
where a wrong answer is invisible. A histogram of the wrong shape looks exactly
as plausible as one of the right shape. So: 64 columns because it divides 256
and an uneven fold draws an even ramp as a comb; the peak excludes the end
columns, or a night scene scaled against its own black spike is a flat line
with no information in it; heights are clamped into the plot; and "0%" is kept
distinct from "<0.1%" and from "—", since an indicator reading "clipped" over
a figure reading "none" is a panel contradicting itself.

Clipping counts a *pixel* with any channel at an extreme, not a channel. Any,
because a blown red has no gradation left in it however much green and blue
still hold — and it is the saturated highlight, the sunset and the red jersey,
that clips first and recovers worst. Per pixel, because counting channels can
report 200% of a frame clipped, and a percentage above 100 is a readout nobody
trusts again.

Two affordances for it, which NFR-A11Y-3 asks for: a bar standing at the end
of the plot the tones are piling against, and a figure saying how much. Either
alone reads.

The panel sits directly under the capture metadata and above every control,
because it is what the controls are judged against. It is hand-built rather
than generated, and ARCH §4.3a is untroubled: a histogram is not an operation
— no parameters, changes nothing, answers a question rather than asking one —
and nothing in it reads a parameter out of a descriptor.

Three plot colours and a neutral luma trace join the palette. That is the
swatch's exception rather than a second one: a per-channel histogram has to
say which channel, and no achromatic treatment distinguishes red from blue, so
the hue is data exactly as the image beside it is. Held well back from full
strength for the reason the theme preamble gives.

The bounded, non-parking map wait moves out of `AdjustPass` into
`readback::await_mapping`, shared with the histogram's transfer. Thirty lines
of load-bearing reasoning about frozen interfaces and lost devices, and two
copies of it would have drifted.

The histogram describes the frame on the canvas, so it is in the output colour
space FR-DSP-7 asks for, and when zoomed it describes the visible region — a
photographer inspecting a highlight at 4x is asking about that highlight. A
device that cannot build the reduction loses the histogram and keeps the
photograph.

Still to do for FR-DSP-7: the pixel colour readout under the cursor.

324 tests pass, clippy and fmt clean.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-17 09:55:40 +02:00
dtourolleandClaude Opus 5 9b2ee0d0eb Show the colour mixer as three runs of twelve, each row a colour
Build and test / Desktop (Linux) (push) Successful in 17m20s
Build and test / Layer separation (push) Successful in 33s
🐳 Android image / Build and push (push) Successful in 2s
Build and test / android-image (push) Successful in 2s
Traceability / Requirement traces (push) Failing after 26s
Build and test / Android (aarch64) (push) Failing after 8m59s
The mixer was thirty-six sliders reading "Hue / Sat / Lum" twelve times
over with nothing saying which band any row belonged to. The identity was
there all along — the descriptor declares param.mixer.orange.sat and BANDS
carries orange at 30° — and was discarded on the way out: labels.rs had no
mixer entries, so every key fell through to a derived label that yields the
bare channel name.

A parameter can now say which aspect it adjusts and which subject it
adjusts it on, with the subject's hue where the subject is a colour
(descriptor::Facet). That is data about what the operation does, not a
layout: the mixer genuinely weights pixels around 30°. What to draw from
30°, and in what order to stack the runs, stay in dr-ui (ARCH §4.3a) —
develop.rs brings rows sharing an aspect together and marks the first of
each, and adjust.slint names the run once and draws a swatch, a track and a
readout on one line.

Grouped by channel rather than by band because an edit is almost never
"everything about orange"; it is the saturation of the greens, made by
comparing one channel across neighbouring bands. Twelve band sections put
those twelve rows in twelve different places.

The swatch is the label, which is what makes twelve rows fit where four
did. The band name is not lost: it is the row's accessible label, so the
control is not colour-only, and labels.rs is where the mapping is written
down — including chartreuse as "Yellow-Green" and spring as "Blue-Green",
since nobody hunting foliage scans a list for "Spring".

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-16 16:14:13 +02:00
dtourolle 8ad5c86ff9 Add the library, collections, and trash views; theme from style.yaml
The UI gains the views the catalog work was building toward: a windowed
library grid with ratings and flags, the collection tree with drag-to-add,
and trash with restore. derived_sync pushes thumbnail shards and the catalog
snapshot to the server's derived folder.

Tokens now have one source of truth. build.rs reads style.yaml and generates
theme.slint into OUT_DIR, which answers every existing
`import { Theme } from "theme.slint"` unchanged, because Slint resolves
imports against the importing file's directory first and the include paths
after. Generating into OUT_DIR rather than beside the hand-written Slint is
the point: a generated file sitting in ui/ looks exactly like the files
around it that are meant to be edited, and an edit to it would survive until
the next touch of style.yaml — a bug that hides for weeks. build.rs fails
loudly if a stale ui/theme.slint exists, which would otherwise shadow the
generated one silently and make every palette change vanish with no error.

The palette moves to near-neutral dark with achromatic signalling, so the
accent means "modified" or "active" rather than "heading". Shared components
land in widgets.slint: a token that binds several values into one concept is
a component, not a row in a YAML file.

Adds an optional live-style feature that makes the tokens in-out so they can
be written at startup — a feature rather than the default because it stops
the properties being constant-folded.

serde_norway is the YAML crate: serde_yaml and serde_yml are both deprecated,
and its mappings preserve insertion order, which is what lets the generated
Slint keep the token ordering the author chose.

Assisted-by: LLM
2026-08-09 21:11:38 +02:00