dtourolleandClaude Opus 5
0b20436445
Picks up the lower-completion work a crashed session left mid-debug, with one failing test and no diagnosis. The diagnosis is that the pass is a no-op. Not "does not reduce basin count" — it changes *no pixel's basin at all*, zero of 9216, comparing one plateau iteration against sixty-four. That assertion is the substance of this commit: the original test asserted a consequence (fewer basins) which a working pass need not produce, so it could have been satisfied by weakening it. A no-op check cannot pass vacuously, and it is what turned an opinion into a fact. Three candidate causes were tried and none was it. Exact float equality is genuinely wrong and is fixed regardless — a gradient computed from 8-bit samples is never exactly equal across a region the eye calls flat, so `==` never fires and `<` fires everywhere; `LEVEL_EPS` now sits behind all three comparisons. The test image is not it either: a flat disc, a terraced disc and a constant-slope ramp all behave the same. The finding worth keeping is about the domain rather than the code. On a gradient-magnitude watershed every flat region of the picture is at gradient zero, the global minimum, and a plateau with no descending exit is a minimum — one basin already, nothing to resolve. The plateaux lower-completion is defined for are regions of constant non-zero gradient, which are rarer in a photograph than F1's phrasing implies. That may be the whole answer, or it may be hiding a fourth cause; I could not close it. So `plateau_iterations` defaults to 0. The implementation stays, correct as far as it goes and costing nothing until someone finishes it; the test stays, ignored with its reason; docs/segmentation.md §12 records what was ruled out so the next attempt starts further along than this one did. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
DarkRoom
A cross-platform, non-destructive RAW photo editor for Linux and Android.
Status: early. v0.1 is a remote library viewer — see docs/milestone-v0.1.md.
Documentation
| Document | Contents |
|---|---|
| requirements.md | What the software must do — 122 numbered requirements |
| architecture.md | How it is built — crates, GPU pipeline, data model, sync |
| milestone-v0.1.md | The first buildable milestone |
Building
Desktop:
cargo run -p darkroom-desktop
Android (containerised toolchain, see docker/android):
./docker/android/build.sh cargo ndk -t arm64-v8a build --release
Current state
Working: workspace, GPU context and compute pass, adaptive Slint shell, Android cross-compilation of the core crates.
Not yet working: the zero-copy display path. The build currently uploads frames through the CPU, which is exactly what ARCH §6.1 forbids — measured at 96% of frame time at 4K. Replacing it is spike S1, the project's highest priority.
cargo run -p dr-gpu --example bench --features readback
reproduces that measurement.
Licence
GPL-3.0-or-later.