A spot is a disc, a source offset and four numbers, and it lives beside
`ops` for the reason `masks` and `film` do: the operation trait is
ParamId -> f32, and a list of repairs is neither scalar nor fixed.
Two decisions here are not obvious. The id is derived from the position
rather than counted, because two devices editing offline would each mint
`spot3` for different marks and the sidecar merge would then treat two
repairs as one — from the position, two devices that removed the same
piece of dust agree, and two that removed different ones do not. And
every length is in the frame's isotropic units, not a mixture of those
and shorter-edge fractions: one unit for the radius, the feather and the
offset agrees on a landscape frame and on a portrait one, where a mixture
only agrees on the first.
`rounds` is the arithmetic that keeps a source from reading a
destination. Every spot in one pass reads the photograph as it stood
before that pass, so a spot sourcing from an earlier spot's destination
would copy the mark that spot was removing. Grouping is not a pass per
spot — that is sixty-four dispatches for a case that almost never arises
— it is a new round only when the sources actually collide.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Pushing was not a thing to simulate. It was measured data being thrown
away: Double-X and 2302 each ship five characteristic curves, one per
development time, and this shipped the 6.5-minute column and discarded
four. All five now ship and interpolate.
The axis is real. Double-X runs 4 to 12 minutes, and across it the average
gradient goes 0.472 to 1.034 while Dmax goes 1.19 to 2.56.
The control is in stops, because that is what a photographer means, and one
stop is a factor of about 1.41 in time. That mapping is checked rather than
assumed: against Double-X's own axis it lands within 2% of the 9-minute
column for +1, and near 12 minutes for +2, which are the times the datasheet
gives for exactly that. There is a test.
**Pushing must not recover shadow detail, and this does not.** Across the
whole measured range the speed point moves about a third of a stop while the
gradient doubles; three stops under mid-grey, density goes from 0.008 to
0.035, which is still nothing. Developing longer multiplies what was already
recorded and cannot record what never hit the film. A push built as added
exposure or global contrast brightens those shadows instead and looks
convincing until someone who shoots film sees it, so that property has a
test of its own.
Interpolated in *log* time, because development is multiplicative: 4 to 5
minutes is the same amount of push as 9 to 12, and interpolating linearly
would bunch the control at one end. Clamped at both ends, because past the
published range there is no data and extrapolating a contrast curve invents
an emulsion nobody tested. A stock measured at one process ignores the
control entirely rather than inventing a curve for it -- Portra 800's pushes
are separate *measured* profiles, which is the honest way to offer those.
Costs nothing per pixel and changes no shader. The curves are a per-stock
table, so the interpolation happens on the CPU at bake time, where choosing a
stock and moving its sliders already rebakes. The Vulkan shader is untouched.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
An emulsion is a suspension of crystals. Light sensitises some; development
turns a sensitised one opaque, all or nothing. So a patch of film's density
is a *count* of developed grains, and a count of independent yes/no events
has a variance whether or not anyone wanted texture:
mean = D
variance = D * (Dmax - u * D) / N
That expression is the whole feature. It peaks in the middle of the density
range and vanishes at both ends -- clear film has nothing developed to vary,
black film has nothing left to develop -- so grain lives in the midtones as a
consequence rather than as a "midtone bias" slider.
I was wrong earlier that this needs the detail stage. Nothing in it reads a
neighbouring pixel; the only reason to move it was that grain must be fixed in
film space rather than screen space, and that solves itself: N is grains *per
pixel*, so it scales with the film a pixel covers. Zoom out, each pixel
averages more grains, less variance -- correct, with nothing super-sampled and
nothing filtered. It stays in the fused pass.
Grain goes on the density and *before* the dye, which is the physical order
and not cosmetic. Perturbing the finished colour -- what an effect does --
tints highlights wrong, because that noise never passes through the dye.
Crystal habit lives in `rms_granularity`, the number every datasheet
publishes, now a profile field. It measures exactly what differs between a
cubic emulsion and a tabular one: at equal speed, tabular crystals present
more area per unit silver, so the film reads finer. Delta 100 is quoted near 9
where HP5 is near 12, and that gap *is* the habit. Adding a stock whose grain
is its whole reputation is therefore editing one line, not writing a model.
Three things this cost, all of them worth writing down:
- The default granularity is a colour negative's, blue coarsest. Applied to
Tri-X it put *colour* speckle on a black and white photograph. Monochrome
stocks collapse it at parse, where every other per-layer table is already
replicated from the one measured channel.
- Helpers cannot read uniforms. The composer prefixes a uniform with its
operation's id and rewrites references inside a fragment body only;
helpers are shared and deduplicated, so a bare `gn0` names nothing.
`film_lut` already took its size as an argument for this reason, and now
says so.
- The end-to-end test compares the shader against the CPU model, and grain
is stochastic, so that comparison now runs with grain off. Which means a
grain that never left the CPU would look exactly like a passing suite --
hence a second test that grain off is bit-identical, one grain per pixel
moves it, and ten thousand move it less.
Not here, deliberately: no grain slider. The parameters are physical and
`rms_granularity` is the honest place to scale one from, but its range wants
choosing rather than guessing. Nor a film format -- 35 mm is assumed, and
medium format at the same stock is far less grainy per unit of picture.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Nothing here is film simulation. These are lints that fail master today,
under the -D warnings CI runs with, mostly from a toolchain that learned
new ones rather than from anybody's code -- `is_multiple_of` and the
derivable `Default` did not exist as lints when this was written.
They are fixed rather than allowed, and by hand rather than by trusting
`cargo clippy --fix` wholesale: its automatic pass split a derive in two
and left a stray blank line, which is the sort of thing that is correct
and still wrong to commit.
The four that needed a decision rather than a rewrite:
- The distance transform's inner loop writes through its iterator now.
`q` stays, because it is the position the parabola is evaluated at as
well as the index it is written to -- the lint is about the write.
- `to_source` and `to_proto` take `self` by value. Their receiver is
`Copy`, so this is the same machine code and the honest signature.
- The export path's return type is five levels deep and now has a name,
plus a line saying why the `Option` wraps the `Result`: `None` is
cancellation, which is not a failure and has no error to report.
- A test fills a range instead of looping over one.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
CI runs cargo fmt --check and clippy -D warnings, and this branch had
never been through either. Both would have failed it.
The bulk was the generated colour tables: eight significant figures where
an f32 carries about 7.2, so the eighth is noise that rounds away at
compile time and clippy's excessive_precision says so 109 times over.
Fixed in the generator rather than only in the file, so it stays fixed --
and the file is trimmed in place rather than re-derived, because
regenerating it needs a colour-science stack that has nothing to do with
the defect.
The format! in the composer is mine too, from extracting the rendering
tail: the braces in it were escaped because the text used to live inside a
larger template, and once extracted the escapes are noise and the call
formats nothing.
Also here, and clearly not mine: an unused import and a shadowed binding
in dr-gpu, and an unused import in a test. They are pre-existing --
clippy has been failing on master before this branch existed, on lints
like is_multiple_of that arrived with a toolchain rather than with
anyone's code. Fixed because CI cannot go green around them, and called
out because a merge commit is a bad place to quietly edit someone else's
crate.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The stock model rendered correctly and nothing could ask for it. This is
the picker, and the sidecar key that makes the choice outlive the session.
How the choice persists was the open question, and the answer was already
written down twice in sidecar.rs: `rating` is a top-level key "because a
rating is not an edit", and `masks` are one "because a layer is not a
scalar". A stock is that kind of thing -- a choice of material, not a
number a slider moves -- so it is a top-level key too.
It stores the **id**, not an index. Stocks are files that users add, so an
index would mean installing a profile silently changed which film every
existing photograph had been developed on. A name this build has no
profile for still round-trips untouched, because the alternative is that
syncing to an older phone quietly un-develops the picture.
Only the names travel. Turning one back into tables needs the profile
database, which dr-pipeline deliberately does not link, so `Version::apply`
clears the film and the session re-bakes -- after the parameters, because
the bake reads the film's own exposure sliders and the print balance is
solved against them. That is also why moving those sliders rebuilds the
lookup where no other control in the panel does: an enlarger's filtration
depends on how the negative was exposed.
The panel keeps its rule. It still names no operation and still generates
every control from a declared parameter kind; the stock gets a bespoke
control beside those, exactly as the mask stack does, and for the same
reason. The film's exposure and print exposure arrive as ordinary
generated sliders.
Two defaults worth stating. Picking a colour negative prints it, because
an unprinted one is an orange strip and offering that as the first thing
somebody sees after choosing Portra reads as a bug rather than as a
choice -- the toggle is there for anyone who wants the scan. And a paste
carries no film: a preset is a parameter map, and a stock is not a
parameter, so pasting one would paste a choice the clipboard never took.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The stock model landed in dr-film with no way to see it. This is the
pipeline node, the two texture bindings it reads, and the end-to-end test
that proves the shader agrees with the model.
The design point is that a film simulation is not an adjustment. Every
other node changes a picture; this one makes it. A stock's characteristic
curve does the camera profile's base curve's job -- from measurements
rather than from a curve somebody drew -- so running both renders the
scene twice: the camera's rendering, and then a film's rendering of that.
It looks like neither, and it reads as a colour-management bug with no
colour-management bug to find.
So `Operation::renders` is new. A node declaring it takes camera RGB and
hands back linear sRGB, and the composer emits neither the base curve nor
the conversion out of camera space. Both halves move together, and the
composer keeps them as one string precisely so that getting half of it
right is impossible.
The tables are not parameters, for the reason vignetting's coefficients
are not: they are measurements. dr-pipeline declares the layout as a plain
struct and keeps its no-dependency property; the two crates share no types
on purpose. `EditGraph::set_film_tables` offers them to every node rather
than to the one that wants them, because knowing which concrete type is
which is what the graph is organised not to know.
Bindings 4 and 5 follow the masks precedent: declared unconditionally so
one bind group layout serves every generated shader, bound to 1x1
placeholders when no stock is loaded. Both are interpolated by hand with
textureLoad -- this pipeline binds no sampler, and adding one for two
lookups would cost a binding in every shader. Uploads are keyed on content
so an unchanged stock does not push half a megabyte across the bus per
frame.
The end-to-end test earned its place immediately: it found the density
lookup being filled z-fastest while a 3D texture upload wants x-fastest,
so the red and blue axes were transposed. Green matched exactly, which is
what that bug looks like -- a plausible photograph of the wrong colour,
and one that every unit test on either side of the seam passes. dr-film
now pins the layout in a test that needs no device, and states it where
the field is declared.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
`cargo fmt --check` is a required step and had drifted across 45 files. Most of
it arrived this week: several operations were written in parallel worktrees and
merged by hand, and a hand-merge resolves conflicts without ever running the
formatter over the result.
No behaviour changes — this is `cargo fmt --all` and nothing else, kept as its
own commit so the next reader can skip it wholesale rather than search it for
one that matters.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Sharpening, noise reduction and clarity were written in parallel and each
rewrote the same two tests, which had counted one fused block per operation —
true only while every operation was a point function.
Kept the exclusive-or formulation: each operation must reach exactly one of
the two stages. A count cannot tell "moved to the detail stage" from
"vanished from both", and that ambiguity is what broke these tests three
times over.
The merge left two fragments of the versions it replaced — a loop over a set
that no longer exists, and the tail of an assertion whose head was gone.
The loop is not restored: `point ^ neighbourhood` already asserts per
operation what it checked over the set. The assertion is, because it catches
a different fault from the exclusive-or — a block in the shader that nothing
in the chain asked for, rather than an operation in the wrong stage.
Capture sharpening and noise reduction were written in parallel and both
claimed `order: 110`; the codegen refuses that, which is the guard working —
two nodes at one order is an ambiguous pipeline and operation order changes
the result.
Resolved in noise reduction's favour, for the reason its own `placement:`
block already gives: denoising is a repair and everything else in this stage
is an enhancement. Sharpening or adding clarity to a noisy frame amplifies the
grain along with the detail, and no later pass can separate them again. So the
detail stage now runs noise reduction, capture sharpening, clarity, texture,
and the other three shift up a slot to keep the multiple-of-ten convention the
rest of the chain uses.
Noise reduction was also missing the required `attributes:` key. The order
collision aborted the build before the attribute check could report it, so it
arrived looking like one fault and was two.
A layer holds a full chain and fuses it into the colour dispatch, so the
panel - which names no operation - would have offered a noise reduction
slider inside a local adjustment. It could not have worked: the detail stage
is its own dispatch, running after the masks are already applied, with
nowhere to be handed one layer's mask. The control would have moved and done
nothing. Filter the layer's chain to the operations that can honour it.
Activating every operation now activates a kernel too, and a kernel emits no
block in the fused shader. Assert that each operation reaches exactly one of
the fused pass and the detail chain, rather than counting fused blocks
against the length of the chain.
A test that cannot be run cannot be checked by running it, and a number
copied out of a test run agrees with whatever the code did on the day.
Each asserted kernel width, tolerance and overshoot bound now carries the
arithmetic that produces it -- the shorter edge, the sigma, the
truncation at two sigmas, and where the rounding falls -- so a reader can
verify the expectation against the recipe without a GPU or a compiler.
Also records the two places where a bound is a bound and not a
measurement: the tolerance in the frame-fraction test is exactly what
rounding a kernel to a whole pixel costs on the smallest frame it uses,
and the halo test's floor and ceiling bracket a peak derived from the
step, the soft limit and the midtone taper rather than from a run.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The fused-fragment check in lib.rs cannot see a detail pass: it is a
separate shader composed at a resolution compose() never knows. The
kernel's own test now scans the block the composer wrapped, with comments
stripped so prose about the keyword cannot fail a test about the code.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
An active detail operation may emit no pass at a given render scale - the
honest answer for a sensor-sized radius on a heavy proxy. The fused composer
cannot see that, having no resolution to consult, so it had already stopped
short of the output transform and the frame died on a storage-format
mismatch. Compose a bodyless resolve pass in that case so the output
transform still happens exactly once.
every_operation_can_be_activated_together counted one block per operation
in the chain, which was true only while every operation was a point
function. A neighbourhood operation is a dispatch of its own and emits no
fused block, so the count now excludes the operations the detail chain
names, and each of them is separately asserted absent rather than the
comparison being loosened.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Capture sharpening as a two-pass unsharp mask in the detail stage: blur
along x, then along y, each pass applying a one-dimensional high-pass to
luminance so the composite preserves a flat field exactly and matches the
textbook kernel on any locally one-dimensional edge.
The radius is stated in source pixels and converted once per render, so a
radius tuned on a fit view is the radius the exported file gets. Below one
render pixel the operation declines to draw rather than showing sharpening
the file will not contain, and emits a single pass-through that still
carries the output transform.
The develop session now renders through render_detailed, which is what
lets an active neighbourhood operation reach the screen at all.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Checkpoint committed by the coordinator, not by the authoring agent: the
session hit its API limit mid-task and left this work uncommitted. Committed
so it survives, NOT because it is finished - expect failing tests and
half-applied changes. The agent resumes from here.
Checkpoint committed by the coordinator, not by the authoring agent: the
session hit its API limit mid-task and left this work uncommitted. Committed
so it survives, NOT because it is finished - expect failing tests and
half-applied changes. The agent resumes from here.
Checkpoint committed by the coordinator, not by the authoring agent: the
session hit its API limit mid-task and left this work uncommitted. Committed
so it survives, NOT because it is finished - expect failing tests and
half-applied changes. The agent resumes from here.
The declaration in ops/tone_curve.yaml has claimed per-channel curves since
it was written — it is the justification for the operation carrying both
`tone` and `colour`. Only the master curve existed. This is the other three.
The master runs first and the channels grade its result. Both orders are
real images and they differ visibly, so the choice is made and written down
rather than left to the loop: a point placed on the blue curve should act on
the tone the photographer can see, which is what the master has already
produced. The other order anchors the grade to tones the master is about to
move, so adjusting contrast slides a warm shadow up into the midtones.
Every id that existed before today is spelled exactly as it was. The master
curve keeps `p2_y` and the new curves take `r_`, `g_` and `b_` prefixes, so
a sidecar written when there was one curve loads, means what it meant, and
renders the same shader — asserted on the generated source, not on the
parameter values. Nothing needed a version check because nothing was
renamed.
Each curve reaches the shader only when it has been moved off the diagonal,
so an S-curve and no colour work generates what it generated when this
operation held ten parameters instead of forty, down to the uniform names.
The monotonicity guarantee is enforced per curve: a coincident pair on blue
divides by zero exactly as thoroughly as one on the master.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The fused pass hands a fragment a colour and no coordinate. That is what buys
one dispatch for a whole edit, and it is also a wall: sharpening, noise
reduction, clarity, texture, dehaze and spot removal are each defined by what
the neighbours are doing, and FR-DEV-3 and FR-DEV-8 ask for all six. None of
them could be written at any price.
So there is now a detail stage. An operation implements `Operation` for its
parameters exactly as before — the panel, the sidecar, the history and the
presets all work unchanged — and additionally returns `Affects::Detail` and a
`DetailStage` yielding one pass per dispatch. `Affects` grows the third variant
`docs/requirements.md:250` designed and nothing had cut.
Where the stage sits is a colour-science decision, not an arrangement of
convenience. It runs after every point operation and every mask layer, so an
amount chosen against a tone curve survives the curve moving; in linear sRGB
after the camera matrix, because camera RGB has no luminance to sharpen
against; and before the output transform and the clip, because FR-DEV-2 allows
one quantisation and a highlight clipped before a convolution grows a dark
ring. The fused pass therefore ends one of two ways, and when a detail stage
follows it hands on unclipped f16 and the last detail pass encodes.
At render resolution rather than on the source, which is the whole of FR-DSP-1:
a pass before the framing prologue would cost 24 MP to draw a 2 MP preview.
`RenderScale` is what makes that survivable — a radius is stored as a fraction
of the frame's shorter edge, exactly as a mask feather already is, or as a
count of source pixels, and converted per render. It also reports when a radius
is smaller than a proxy pixel rather than drawing a plausible lie; zooming to
1:1 makes the preview exact with no second path.
`Invalidation` gives FR-DEV-3d something to mean. Moving a detail parameter
leaves the colour key alone, so `AdjustPass` keeps the linear intermediate and
skips the fused dispatch: dragging a sharpening slider costs a convolution.
Moving exposure does re-run the detail passes, because they read what the
colour pass wrote, and there is no arrangement of keys that avoids it while
keeping sharpening after tone.
Validated by a separable box blur that is not a develop operation, behind the
`detail-probe` feature and absent from a shipping build. An abstraction with no
consumer is a guess; a box blur's answer is known in closed form, so the tests
assert every byte of the ramp rather than that the edge got softer.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Colour came from whichever matrix rawler happened to key `D65`, the second
one was discarded, and the rendering was left linear. That is the dcraw
default, and FR-DEV-3e names it as the reason people abandon a converter in
the first hour: correct in the abstract, flat and poor on skin in practice.
The decoder now builds a camera profile.
- `ColorMatrix1/2` and `CalibrationIlluminant1/2`. rawler surfaces these as
an illuminant-keyed map — for DNGs from the tags, and for native formats
from its own camera database — so a Canon CR2 arrives with a tungsten
matrix and a daylight matrix exactly as an Adobe DNG of the same frame
would. Dual-illuminant support is therefore not a DNG feature here.
- `ForwardMatrix1/2`, read straight from the root IFD, because rawler parses
them and never surfaces them. Where a file carries both, they replace the
inverted colour matrix: the same relationship measured in the direction
rendering actually wants, rather than an inversion that amplifies the
measurement error exactly where skin lives.
- `AsShotNeutral`, used to estimate what the scene was lit by and to
interpolate between the two calibrations in mireds. The estimate is
circular — the temperature needs a matrix and the matrix needs the
temperature — so it is a fixed point, three rounds, as Adobe's SDK does it.
Bodies calibrated at neither D65 nor A stopped rendering uncalibrated as a
side effect: a Phase One IQ3 carries D55 and D75 and used to get no matrix
at all.
And a base curve, applied per channel in camera RGB between the last
adjustment and the conversion out of camera space — a toe, a steep midtone
and a shoulder, which is the difference between a photograph and a scan of
one. It is not an edit: no slider, nothing in the sidecar, because it
belongs to the body rather than to anything anyone decided, and a sidecar is
shared between bodies. It is not a develop node either, and `ops/README.md`
now records why. It evaluates on the tone curve's own spline rather than a
second copy, so a profile author placing a control point and a photographer
dragging one mean the same thing by it.
The curves are data. `core/dr-decode/profiles/base_curves.yaml` ships inside
the binary as a floor and is superseded by any copy on disk carrying a
higher `version:`, so a body can be added and distributed without a release
— and, under the GPL, contributed. The comparison runs both ways: a stale
pack cannot hold an upgraded binary back at last year's rendering.
Canon EOS 6D and R6, Nikon Z 6 and D750, Sony A7 III and Fujifilm X-T3 ship
with their own curves. Every other body gets a conservative default, which
is much closer to right than the identity is for any of them. A JPEG gets
none — it has already been rendered once, by the camera.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Selecting a mask layer silently re-points about thirty controls at that layer's
chain. Same panel, same order, same sliders, different meaning — and the only
thing that said so was a sentence in the panel above, which a photographer
reaching for the exposure slider has no reason to read. An exposure change
lands on the whole frame when it was meant for a face, or the reverse; both are
silent, and both are discovered later. `ui-navigation.md` §1.1 calls it the
dangerous one and it is: the others in that document cost time, this one costs
work.
The remedy is the classic one for a modal fault — make the mode visible — and
the application already had the pattern. Crop arms a canvas interaction, draws
an overlay, gives the column one job and is left by the control that entered
it. Local masking is the same animal built as a peer panel, and that is what
created the ambiguity. So `crop-mode` stops being a bare boolean and becomes
one value of a three-state mode, which is the point: two modes could both be on
before, and now that is not a state the interface can be in rather than one it
is tested against.
**One strip, not two.** The mode control was going to sit beside the group
strip that filters the adjustments, which is two controls above one column
answering the same question — what am I working on. They are one control now,
`Crop · Local │ All · Light · Colour`, which is the shape Lightroom Mobile's
bottom strip has for the same reason. The two halves are different kinds of
state and are drawn differently: a mode is a chip that fills with the accent
when it is on, a group is a word with a rule under it. That difference is what
lets both be read at once, which they routinely are — picking Light while a
mask is selected filters *that layer's* chain and does not leave the mode.
Dropping the scope on a group press would be the same fault coming back from
the other end, and would make Light mean two things depending on where it was
pressed.
The strip stays pinned above the develop column rather than moving to the top
of the canvas as the document proposed. The half that filters the column
belongs to the column, and the photograph is the subject. The canvas keeps one
button, which now names the mode it leaves rather than saying "Done" — that was
unambiguous with one mode and would not be with two — because the column can be
closed on a narrow window and no mode may be inescapable.
Entering a mode is a side effect, so Rust owns it rather than the strip writing
the property: crop drops the zoom, local turns the overlay on, and leaving
clears the selection. That last one is the fix. The "Overlay" and "Select"
toggles are gone because they armed things that are simply what the mode *is* —
a mode that has to be switched on separately is one you can enter and have do
nothing. Escape and the Android back gesture join `back_step` as one
`LeaveMode` rather than a second exit concept, and the mode is left before the
zoom is: it was entered later, and it is the bigger step back.
The heading is where the scope goes. Not a caption beside the panel, the
heading *of* the panel that changed — `ADJUST` becomes the layer's name, the
same string the selected row in the stack shows. That is the difference between
describing a hazard and removing it.
**Handles on the photograph.** A linear or radial mask could be created and
then not moved, so a radial sat at the centre of the frame at its default size
for ever. Three faults stood in the way of drawing one.
The first is that a gradient did not render at all until the model had run. The
rasteriser was built on the way out of `segment` and the array's size was read
*off* the segmentation, so a gradient added to an unsegmented photograph
produced nothing — silently, in the same way exports and thumbnails once did:
the shader still emits the layer's block and the empty placeholder multiplies it
by zero. The proxy size is a property of the photograph. Both are derived from
it now, and deliberately at the same size rather than by coincidence, because a
subject's distance field is sampled against that array.
The second is hit-testing. A handle is drawn in output coordinates and stored
in source ones, and between them lie the crop, the zoom, the pan, the
straightening and the turns. `Framing::source_at` is `wgsl_prologue` evaluated
on the CPU, kept in that file beside it so that keeping the two in step is one
file's problem — a handle mapped through anything less drifts off the mask the
moment the view moves, which is exactly what masks are rasterised in source
space to avoid.
The third is that a drag is a displacement, not a destination. Each handle
answers to the movement of the pointer since the press, applied to where the
mask was when the press landed. Snapping the handle to the pointer instead
jerks it by up to half a touch target on the first press, and the target is
finger-sized because a tablet has no hover to reveal a control and no modifier
to qualify it.
A ramp gets three handles — centre, width, angle. An ellipse gets three too:
centre and one per semi-axis, the major one carrying the direction as well as
the length, because where an axis is put says both. It had a fourth, and it is
gone: standing off the shape by a fixed distance, the rotation arm began
outside the photograph at the size a new radial is created at, so the first
thing anyone saw was a control they could not reach without first shrinking the
mask.
Two faults here were found by looking at the screen rather than at the source,
both of the kind that cannot be found any other way. A `1px` rule with a size
and no position is *centred* by Slint, so the seam between the photograph and
the column was a hairline down the middle of the panel, through the histogram
and every slider under it — twice, once in `app.slint` and once in
`AdjustPanel`. And handing Slint a fresh model for the handles on every pointer
event made the repeater rebuild its items, taking the `TouchArea` holding the
gesture with them: the handle jumped once and then went dead under a finger
that was still down. `develop.rs` carries the same warning about the parameter
rows, where it broke slider drags; the model is rewritten in place now.
The tests worth having are the ones about ambiguity and about the map. That the
same row reads the frame's value, then the layer's, then the frame's again is
§1.1 in one assertion. That dragging a handle onto another gradient's matching
handle *produces* that gradient closes the loop between the two directions of
the framing map, through a view that is cropped, zoomed, panned, straightened
and quarter-turned at once — a one-legged map is invisible when the framing is
neutral, because then both legs are the identity.
Not done here: the histogram still reports the whole frame while the sliders
edit a layer. That disagreement is real and is N3's, which this unblocks. The
strip has room for a Brush entry beside Crop and Local when the painted masks
land in the core, and it needs nothing here but the canvas interaction.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
A linear mask at 45° was not at 45°, and a radial with equal radii was an
ellipse. Both on every photograph that is not square, which is all of them.
The geometry is stored in normalised coordinates so that a mask survives a
crop, a zoom and an export at another size — that part was right. What was
wrong is that a *distance* was being measured in those coordinates too, and a
fraction of the width is not the same length as a fraction of the height. So
`dot(uv - centre, axis)` measured the ramp in a space one of whose axes is
squashed against the other by the aspect ratio, and the iso-lines came out
sheared: on a 3:2 frame a ramp asked for at 45° arrives at about 34°.
Nothing announces it. The stored numbers are exactly what was written, the
shader is doing exactly what it says, and the only place the fault exists is
between the photographer's intent and the picture. It has been invisible so far
because there is no way yet to place a gradient by eye — the handles that make
it visible are what turned it up.
So distances and angles move into the frame's own isotropic units: y spans
`0..1` and x spans `0..aspect`, which makes a circle round and 45° a real
diagonal. The centre stays a plain fraction of each axis, because it is a point
and a point has no such problem — and because that is the space a click arrives
in. `frame_delta` is the one conversion and must stay the only one; the mask
array's own dimensions carry the aspect, so it costs no uniform.
The sidecar format does not change. What changes is what the numbers mean, and
the only geometry in the wild is a default that has never been movable.
The two tests are at 96×64 rather than square, which is the whole point: on a
square target this bug cannot be reproduced, and every existing mask test was
square. Both fail without the conversion — the radial reaching 28px sideways
where it reaches 19px down, and the diagonal landing on the wrong side of the
line it is supposed to lie along.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The last line of FR-DEV-3, and the mask ARCH §5.4 was written for. darktable
rasterises drawn masks on the CPU and users call the result unworkable; the
architecture's answer is that a stroke arrives as *parameters* and the device
draws it. This is that, from the model through the sidecar to the pixels — but
not the finger: the canvas is somebody else's change, and this leaves it a
seam rather than reaching into it.
**A stroke is a swept disc along a polyline**, plus erase, radius, hardness and
flow. `MaskSource::Brush` holds an ordered list of them, and the order is the
mask: an erase after an add takes it away and the same pair reversed does not.
Nothing about it is pixels, which is what makes a mask that costs a line of
text, diffs by the gesture, and survives a crop, a straighten and an export at
any size — the properties a stored raster has none of, and the same argument
the region ids were chosen for.
Two things keep the point count honest. While the finger is down, a position
closer to the last than an eighth of the radius is dropped: a touch screen
reports 120 a second, so a finger held still for five seconds is six hundred
points in the same place, and simplification would only remove them once the
gesture had ended — after every frame in between had drawn all of them. When
it ends, Douglas–Peucker at an eighth of the radius removes what a disc that
wide cannot express: a swept circle moved by r/8 moves its own edge by r/8,
which is inside the soft part of any brush. Coordinates snap to a
ten-thousandth of the frame on the way in *and* are written at that precision,
so a round trip is exact rather than nearly exact — a file that drifts in the
sixth decimal every save is a per-field merge conflict a day, over nothing.
**Cost is why the strokes are not drawn by the full-screen triangle the other
masks use.** A swept disc is the minimum distance to any of its segments, so a
stroke over the whole frame costs `pixels × segments` and both terms grow
together — the quadratic that is darktable's problem moved onto the GPU rather
than solved. Each stroke is instead drawn over its own bounding box, grown by
the radius, so the rasteriser never invokes the shader for a pixel the stroke
cannot reach: `area(box) × segments`, which for a dab or a swipe is a small
fraction of the frame. A gesture past 256 points continues as a second stroke
for the same reason, since a shorter stroke has a smaller box.
Add and erase are `dst + a(1 - dst)` and `dst(1 - a)`, which are exactly a
source-over and a one-minus-source blend — so they are blend state, not
arithmetic, and no pass ever reads the slice it is writing. That is what
permits one draw per stroke at all. Within a stroke the coverage is the
*minimum* distance over its segments rather than a sum: a path that crosses
itself must not build up where it did, or every circle and every scribble
would be blotchy wherever consecutive dabs overlap, which is everywhere.
Not a distance field, deliberately. `dr-segment`'s transform documents the two
conditions that make CPU work right there — once per mask edit, over input
already CPU-side — and a stroke fails both: it changes while the finger moves,
and its input is a handful of coordinates that never needed to be pixels. It
also needs no transform, because the distance to a swept disc is closed form.
A stroke is the one mask whose distance field is known without computing one.
An unpainted brush layer is inactive rather than empty, which is not an
optimisation: `invert` turns empty into everything, so a layer created with
invert already set would apply its adjustment to the whole photograph before a
single stroke was made. That is the loud, confident kind of wrong this codebase
refuses everywhere else a mask can go missing, and there is a rendered test for
it.
The tests read pixels back off a device rather than checking that the two
halves agree with each other. What they pin down is what is silent when wrong:
the y flip between mask space and clip space, which a centred stroke would not
notice; a bounding box not grown by the radius, which makes a tap draw nothing
at all; an aspect ratio ignored, which makes a dab an ellipse on any frame that
is not square; a stroke doubling back and building up; and an erase that lost
its place in the order and put back paint the user had taken off.
Not done here: the interaction. The canvas needs to begin, extend and end a
stroke on the active layer, and `DevelopSession::rasterise_masks` still returns
early without a segmentation — it takes the proxy size from one, and a brush
needs no model to have run over the photograph first.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Reported as a thumbnail bug; the export had it too, which is the serious
half. You would have exported a photograph missing every local adjustment.
Both called the unmasked `render`, and the failure is silent by
construction: the generated shader always declares the mask binding and
always emits a block per active layer, so binding the empty placeholder
multiplies each of them by zero. No error, no warning, no missing texture —
the adjustments are simply not there. From inside either path there is
nothing to see.
Every path that produces pixels now goes through one helper that binds the
array, and that is the point of it being one helper rather than three
correct call sites. The array is rasterised in source space at proxy size
and sampled through the framing map, so one array serves every output size:
a 256px thumbnail and a 24 MP export bind the same texture.
Three tests, and the first is the fault stated directly — render the same
edit with and without the array and assert they *differ*. If binding it ever
stops mattering, the masks have stopped reaching the shader. The third
checks the masked share of the frame is the same at 32px and 128px, because
"both non-empty" would pass while a mask that scaled wrongly still ruined
every thumbnail.
A strip of groups over the adjust panel — Light, Colour, Detail — derived
from the attributes the operations declare. `adjust.slint` names none of
them: the strings arrive resolved and the panel only draws them, so a new
operation joins the right group by saying what it is and this file does not
change (FR-DEV-3a).
A group nothing carries is not offered, so a tab never opens onto nothing.
Geometry is left out because its one operation prefers an on-canvas widget
and is skipped by the row builder — a Geometry tab would be empty while
`GeometryPanel` holds the real controls. The strip appears only when there
is more than one group to choose between; a single tab is a control with one
option.
The selected group is underlined rather than filled. The accent means
*modified* everywhere else in this interface, and spending it on "which tab"
would blunt the one signal the panel has.
**The trap, and it nearly bit again.** `op_index` on a row counts over every
capability, not over the ones a filter kept — it is how a row routes back to
the core. Renumbering it while filtering would make a slider drive a
different operation, which looks like a rendering fault rather than a
routing one. `rows_filtered` keeps `enumerate` over the full list and only
`group_head` is a position within the emitted rows; a test moves a value
through a filtered row and checks it lands where it was asked to.
Six tests, including that a nonsense index falls back to showing everything
rather than to showing nothing.
Tool tabs need a taxonomy, and the taxonomy was the problem: a table in
`ui/` mapping operation to tab breaks FR-DEV-3a, and a `group:` field risks
what `ui-refinement.md` condemned `starts-group` for — the core deciding
where the panel draws things.
`Attribute` threads the needle. It says what an operation *is* — tone,
colour, detail, optics, geometry, effect — which is the same category as
`ParamKind` and squarely on the core's side of ARCH §4.3a's line. What is
drawn, where it sits and whether it is visible stay the frontend's. There is
no attribute for "the third tab", the enum's order is declaration order
rather than screen order, and a frontend may render these as tabs, as
headings, or ignore them.
The payoff is that a tab strip can be *derived*: the groups are the
attributes present in the capability list, so the interface names no
operation and needs no table to keep in step. An operation joins the right
group by declaring what it is, which is the one thing its author is well
placed to say.
Plural, because the tone curve is genuinely both — an RGB curve is tonal and
the per-channel curves are chromatic, and filing it under one would hide it
from half the people looking for it.
Required and non-empty, enforced in `build.rs`, and the failure was checked
by removing the line rather than assumed. An operation with no attribute is
invisible to a panel that groups by them; a build that stops costs ten
seconds, a control nobody can find costs more. The vocabulary is closed for
the same reason: a typo would otherwise invent a category holding exactly one
operation, which looks like a deliberate one until somebody counts.
Six tests over the real chain, including the hand-written operations that
`build.rs` never sees and so cannot check.
The watershed hierarchy does not survive a photograph, so local masking
stops depending on it. A layer can now be one recognised object, and the
object's own coverage is the mask.
`Options::watershed` defaults off. It costs ~80 ms plus a full-resolution
readback to produce a ladder that collapses, and paying that on every
photograph buys a control that misleads. Kept switchable rather than
deleted: the passes and the hierarchy are correct in themselves and it is
the merge criterion that fails, which is a change to one function.
Masks now rasterise in **source** space at proxy resolution and are sampled
by the composed shader after the framing map. That fixes a real bug: they
were rasterised in output space, so zooming slid the photograph underneath
a mask that stayed pinned to the viewport, and cropping moved every
adjustment to a different part of the picture. Doing it this way also
leaves the framing map in exactly one place — a second copy in the mask
shader would have been a second thing to keep in step, failing only when
straightened.
A subject is stored as identity, not pixels: the mask is megabytes and is
reproducible by running the same model over the same image, so the sidecar
carries the index, the class and the score, and the session carries the
pixels. The class is there to be checked — if instance 3 comes back a "car"
where it was a "dog", something changed and the layer is stale rather than
silently masking the wrong thing.
The overlay now draws instances and is transparent everywhere else. The
region version covered every pixel and so hid the photograph it was drawn
over; the question it exists to answer is whether an outline follows the
subject, which you can only answer by seeing both.
`examples/local.rs` is the worked example: subject in colour with the rest
monochrome, and the subject lifted out of its background. Run on a 5472x3648
CR2 it finds two people and two cars, and the colour-pop keeps her hat and
hair while the wall and grass behind go grey.
Two things, and the second is why the first matters more than expected.
Mask layers gain a feather, a falloff curve and a morphology, all defined
against a signed distance from the boundary rather than as separate
features — one exact distance field answers "how soft" and "how far" at
once, so dilation is a threshold at -r, erosion one at +r, and closing and
opening are one of each in sequence. The compound pair costs a second
distance field, which is why they are named rather than presented as a
radius that happens to be signed. Types, defaults and sidecar round-trip
only; the field itself is next.
`edge-feather` and `edge-falloff`, not `feather` and `falloff`, because a
radial mask already writes `feather` for the fraction of its radius it
ramps over. Same word, different quantity, different units — sharing the
key would have made an existing file ambiguous.
The diagnostic that provoked this is committed as an ignored test, because
"does the ladder land on things a person means" is the question S15 exists
to answer and it should not depend on whoever still has the script. On
bus.jpg it answers badly: 35,075 regions at blur 2 over an 810x1080 frame,
and cutting that to 400 gives *one* region covering nearly the whole
picture plus 399 noise specks. Not over-segmentation — collapse. Almost
every saddle is near zero, so the merge order joins everything meaningful
before it joins anything spurious, and a global cut spends its entire
budget on grain.
So the granularity ladder does not currently work on a photograph, and the
region masks built on it inherit that. Recorded rather than worked around:
the next commits move local masking onto the model's instances, where the
edge treatment above is what makes a quarter-resolution mask usable.
A mask layer holds a real develop chain, so the develop panel can edit one
with no new controls: select a layer and the same sliders read and write
its chain instead of the graph's. An operation declared in `ops/` tomorrow
becomes locally adjustable by existing, which is the payoff for making a
layer a chain rather than a handful of special-cased parameters.
`segmentation.rs` joins the two arms into the one thing the view needs.
The model reads the image through a neutral graph rather than the edited
one, so a segmentation survives an exposure change instead of being
invalidated by every slider. Arm B failing is not fatal: a missing or
unreadable model leaves a working watershed map, because refusing to
segment at all would trade a working feature for a strict one.
The overlay colours groups by a golden-angle walk over hue. Deterministic
rather than random, so a region keeps its colour across a level change and
the eye can track it; boundaries drawn black over the fill, because two
adjacent groups landing on near hues read as one region and telling them
apart is the whole reason to look at it.
Clicking the photograph creates the layer if none is selected — that is how
a local adjustment begins, and making the user press "add layer" first
would be a step with no decision in it. Shift-click extends, and clicking a
region already selected removes it, so one gesture both adds and corrects.
`segment-readback` is a new dr-gpu feature and not a loosening of
`readback`. The region-graph transfer is once per image on a worker; the
one AC-8 forbids is per frame in the render loop. Sharing a switch would
have forced a build wanting local masking to unlock the other. F3 still
stands and the feature name says so.
The sidecar is authoritative — the catalog is a disposable index and the
RAW is never written — so a mask that does not round-trip is not a
persistence bug, it is lost work.
Layers get their own `[mask <version> <id>]` blocks rather than being
flattened into dotted keys. A layer is not a scalar: it carries a
selection, a geometry and a chain of its own, and encoding a region set as
`m1.region.0 = 12` would be neither readable nor mergeable. The version
uuid is repeated in the header instead of relying on the block following
its version, because "belongs to whichever version appeared above me" is a
relationship that hand-editing, merging and older builds each break
quietly.
Region ids sort and deduplicate on read rather than being trusted from the
file. The mask's identity is the *set*, so two devices writing the same
selection in different orders must produce the same mask rather than
argue about a difference that is not one.
Masks merge by layer id under FR-NC-9, which is the disjoint-survives rule
the parameters already follow one level up: a layer added on the phone and
one added on the desktop both survive. A layer *both* sides edited resolves
wholesale to the higher revision, because half of one selection plus half
of another's opacity is a layer neither person made. A remote deletion is
honoured, or a mask the user removed returns on every sync.
An unknown mask source is skipped rather than guessed at. Applying a newer
format's mask type as the nearest one this build knows would put a
confidently wrong adjustment on the photograph, which is worse than
applying none.
29 new tests. The interesting ones are about silence: a maskless version
clearing the previous image's layers, a bare selection persisting even
though it renders nothing, and a mask naming a version that is not in the
file being dropped instead of landing on whichever block was open.
A mask layer is an ordinary develop chain plus a rule about where it
applies. Nothing in the chain knows it is being masked, so every operation
that works globally now works locally and a newly declared op in `ops/`
arrives with local support already done.
The composer emits each layer after the global chain and before the
conversion out of camera space, which is what a photographer means by "and
*then* lift the shadows on her face". Op fragments write to a `c` they
expect to own, so a layer block shadows it and copies the result back out
through a carrier — assigning the outer one from inside is impossible
precisely because it is shadowed. The fused dispatch survives: three global
adjustments and two masked ones remain one shader, one read, one write.
Masks rasterise on the GPU and never exist in CPU memory (ARCH §5.4). That
is the whole reason darktable's brush masks lag, and it is architectural
rather than tuning, so it is not a thing to inherit and fix later.
The rasteriser is a render pass rather than the compute shader it obviously
wants to be, and the format is why: R8Unorm is not a core storage format,
so a compute path has to widen masks to four bytes per pixel — 768 MB
across eight layers of a 24 MP export, against 192 MB at one byte. A colour
attachment takes R8Unorm happily. The array slice comes from the attached
view, so no slot uniform exists to disagree with where the pass writes.
Region masks index a compacted label field rather than the watershed's raw
basin roots, because a root is a sparse index into pixel space and
indexing a per-region array by one would need a table the size of the
image. Changing a selection then costs a few kilobytes, not a re-upload.
Stored as region ids, not as pixels: diffable, mergeable per-field under
FR-NC-9, and cheap in a sidecar. The ids only mean anything alongside the
segmentation that produced them, so each layer carries that signature and
is treated as stale rather than applied when it does not match — a
confidently wrong mask being much worse than an absent one.
Seven device tests render actual frames and read them back. The unit tests
either side check halves that would both pass if the two agreed with each
other and were both wrong; a mask sampled with x and y swapped satisfies
them and fails these.
The colour mixer emits a code block and a uniform only for the bands that
are set, so which bands are adjusted is part of the shader's structure. The
pipeline cache key was not: it hashed the set of *active operations*, which
is "colour_mixer" whichever band that is.
So a red adjustment and a blue one hashed alike. The second render was handed
the first's compiled pipeline while its uniform was uploaded into a slot that
shader had assigned to another band — whichever band compiled first kept
acting on every subsequent move, and every other slider did nothing at all.
Red is the first band declared, and the one reported as the only one working.
The hash is now taken over the generated WGSL, because the source is what
gets compiled and therefore is the structure. A summary of what went into it
has to be kept in step with every operation's code generation by hand, and
this one had fallen out of step. Values still do not enter it: no operation
writes a parameter value into its source, so a slider drag regenerates
identical text and reuses the pipeline, and one that did inline a value would
have to recompile to be correct anyway.
`each_colour_band_gets_its_own_pipeline` in dr-gpu renders a blue pixel
through one pass with red set first and then blue, and fails on the old hash
with the reported symptom — the blue slider returning the pixel unchanged to
the byte.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The framing prologue built the centred position `p` by scaling with the
source's aspect, then straightened, then permuted the quarter turns. On a
landscape frame those are one space and it worked. Once a turn has swapped
the axes — the rotate button, or a file whose EXIF tag says the camera was
held sideways — they are not: `p` was measured with the source's ruler on a
frame that is no longer that shape, stretching one axis against the other by
(w/h)², which is 2.25 on a 3:2 photograph.
The quarter-turn permutation happened to undo that stretch, so rotation alone
looked right, which is how this survived. The straighten in between did not,
and a rotation in a space whose axes carry different scales is a shear.
`p` is now built in `frame_aspect` — the frame as the user sees it — and the
permutation becomes the one place the two rulers meet: each axis divided by
the aspect it is read from, multiplied by the aspect it is written to.
Asserted on pixels rather than on the generated WGSL, because reading the
shader and reasoning about which space `p` lives in is how the wrong formula
got written in the first place: a disc, straightened by 20° on a turned 3:2
frame, must come back circular by every route to a swapped frame — the
button, the tag, and the two composed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Every clipped sky came out bright pink. Measured, not guessed: developing
_MG_8596.CR2 and looking at the export, the subject renders correctly and only
the saturated region is wrong.
A fully clipped pixel reaches the shader as (1, 1, 1) — three photosites that
stopped counting, carrying no colour at all. The as-shot multipliers are not
neutral, so balancing sends it to (1.93, 1.00, 1.68) on this body, and the
camera matrix turns that into R 2.88, G 0.51, B 2.03. Red and blue clip at
one; green, whose matrix row is far less positive-heavy, does not. Red and
blue high with green low is magenta.
Nothing upstream was at fault, which is why the two previous attempts missed
it: the white balance is correct, the matrix is correct, and the sensor
normalisation is correct. The input simply was not a colour, and correct
arithmetic on a non-colour produces a confident wrong answer.
So saturation is detected before the balance is applied — the last 1.5% of
range, smoothstepped rather than switched, because a hard threshold draws a
visible rim around every highlight and a backlit edge on skin is where that
shows. Above it the pixel is pulled to the neutral of its own brightness, so
it keeps its luminance and loses only the cast.
Verified end to end on the file itself: the sky is white, the skin, the black
dresses and the stone are unchanged.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The generated shader ended with `encode_srgb` and a clamp, so every
photograph leaving DarkRoom had been through sRGB's gamut whatever the
settings page said. Export refused the other three spaces rather than
tag clipped pixels with a gamut they did not contain — correct, and
not something an encoder could fix.
So the output space becomes a parameter of composition. `compose_for`
emits a constant primaries matrix after the camera matrix and before
the clip, and generates the transfer function to match: the sRGB curve
for sRGB and Display P3, a pure 2.199 gamma for Adobe RGB, 1.8 with a
linear toe for ProPhoto. The ordering the camera matrix depends on is
untouched — operations still run in camera space — and sRGB emits no
conversion at all, so the shader compiled on nearly every frame is
byte-for-byte what it was.
The numbers live in dr-types, derived from four chromaticity pairs per
space rather than tabulated. That is not tidiness: the shader encodes
the pixels and the ICC profile describes them, and a file whose profile
disagrees with its own contents is worse than one with no profile. One
derivation makes them agree by construction, and can be checked against
the values the specifications publish.
Profiles are generated here too — minimal v2 matrix/TRC, about 2 KB,
pure Rust, no lcms to satisfy under the NDK. A JPEG carries it in APP2,
a PNG in iCCP, a TIFF in tag 34675. sRGB gets one as well, because
untagged does not mean sRGB, it means guess.
The refusal survives in a sharper form. A `Frame` now carries the space
it was rendered in, and export refuses to label it anything else. The
develop session still composes for sRGB, so a P3 export from the
interface fails with an accurate error instead of producing a file that
lies — the frontend half is a separate change.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Develop edits now save themselves to a sidecar the moment you leave the
image, so until this there was no way to undo one — the mistake was
persisted and the only recourse was to remember the old number.
The history is a stack of snapshots, because the edit graph is already
plain data: `Preset::capture` reduces it to what differs from default and
`Preset::apply` puts it back, so undo is those two calls and nothing else.
A command object per action, with an inverse beside it, would have been a
second thing every operation had to register — and operations are declared
in YAML precisely so that a new one needs no code written for it. A
snapshot cannot fall behind them.
The interesting part is coalescing. A slider drag emits an event per frame
and must be one step, not forty. Nothing in the interface reports a gesture
boundary — the same wall the render coalescing hit, and it is answered the
same way rather than by threading a "finger is down" out of every slider,
curve point and crop handle. What stands in for the boundary is the control
plus recency: changes to the same control within 700 ms amend one step.
Which control is "the same" is asked of the graph, not listed: an operation
whose declared presentation claims a parameter is one where a single
gesture moves several — a curve point carries an x and a y — so those
coalesce as one widget. Nothing in the history names the tone curve.
The compromise, and it is a real one: a control let go of and picked up
again within the window is one step rather than two. Buying the other
answer costs a gesture-boundary signal on every control, which is more
surface than the difference is worth.
The stack is bounded at 64 states for NFR-RES-1 — a develop session stays
open for hours. Sixty-four rather than a byte cap: what is being bounded is
steps a photographer would want back, and a byte cap would give the
elaborate edit the shallowest history, which is exactly backwards.
The session owns its history and every mutator records into it, so the
callbacks in `lib.rs` cannot change the edit and forget to — with a dozen
generic callbacks that would have been one press of undo away from wrong
every time a control was added. Opening a photograph makes its stored edit
the floor rather than a step: it is not work done in this sitting, and an
undo reaching behind it would discard a previous session's edit and then
save that on the way out.
Not yet done, from FR-DEV-5: history is per-session and in memory, and
there are no named snapshots. What mattered was that a saved mis-drag had
no way back at all.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
dr-export could turn a frame into bytes and nothing could ask it to. This is
the button, and the place the bytes go.
**Everything is staged first.** An export bound for the server is written to a
local outbox and uploaded afterwards; offline is not a special case, it is the
same path with a drain that finds the server absent. Doing it the other way —
upload directly, stage only on failure — makes the failure path the one that
is rarely exercised and always broken, and a network drop mid-batch leaves
some exports existing and some not with nothing recording which. Staged first,
an export is finished the moment it is written and the upload is a promise
kept later.
The outbox sits beside the catalog rather than under the cache. dr_catalog's
cache already draws that line: passive entries are a convenience and go under
LRU, pinned ones are a promise and never do. An export awaiting upload is a
promise — the user was told it succeeded — and sweeping it for disk would
destroy the only copy. Bytes are written before the destination record, so a
kill between the two leaves an orphan the drain ignores rather than a record
pointing at nothing.
The status line says "Queued for Exports/2026", never "Exported to Nextcloud",
until it has actually landed. There is a test asserting that wording, because
the tempting shorter sentence is a claim the app cannot keep.
The drain runs on the sync pass, before the shards: a thumbnail shard can be
rebuilt from the originals and the catalog is an index, but a queued export
exists nowhere else.
`DevelopSession::render_for_export` renders the framed size rather than reusing
the frame on screen, which is deliberately viewport-sized (FR-DSP-1) — encoding
that would hand the user a soft, screen-sized file with nothing to say anything
had been lost (FR-EXP-9).
One compromise, recorded rather than hidden: the export runs synchronously on
the UI thread, so the window is unresponsive for the few hundred milliseconds
a full-resolution render and encode takes. Moving a DevelopSession and its GPU
pass to a worker is a larger change than one button earns, and it is batch
export that makes the wait intolerable rather than merely noticeable.
Still missing: the Nextcloud folder *picker*. The destination is typed into
Settings for now. `FolderBrowser` in launch.rs is already the reusable model
for it — it browses a remote tree and nothing about it is specific to choosing
a library root — but wiring it into the settings page needs a listing worker
and browser UI there, which is its own piece of work.
Carries in-flight work from a parallel session — presets, the develop copy and
paste, and the node schema's `presentation` and `enum` support. One misplaced
callback in settings_ui.rs is moved from `render` to `wire`: registered in
`render` it borrowed a `&SettingsController` into a 'static closure and would
not compile, and that file's own docs say render pushes properties while wire
connects callbacks.
992 tests pass, clippy and fmt clean. Traceability 48.3% -> 51.0%.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>