dtourolleandClaude Opus 5
654c11300e
Chasing a reported shear on rotate and straighten. Two tests, and what they prove is that the pipeline is not where it comes from. A circle is the shape that makes anisotropy unmissable: any transform scaling the axes unequally returns an ellipse, and the ratio of its axes is the error. Both a quarter turn and a 20° straighten, on a 3:2 frame, return a circle within 8%. Worth recording because I had a confident and wrong hypothesis first. The quarter turn carries `* aspect.x` on one component and `/ aspect.x` on the other, which reads like an anisotropy of a-squared, and the reasoning that `p` is already isotropic is plausible enough that I changed it. The existing `a_quarter_turn_corrects_for_aspect_across_the_swap` caught that immediately, and these tests then showed the original was right all along: the crop rect is expressed in the *turned* frame and the output axes swap with it, so the factors are the conversion between those spaces rather than a mistake. Reading the shader and reasoning about which space `p` lives in is exactly how a plausible formula gets written twice. These assert on real pixels off a real adapter instead, so the next person to suspect this transform can rule it out in one command. The shear is therefore in the display path — the fit from the framed size to the viewport, or the crop overlay's uncropped render — and not in the geometry the pipeline computes. Not yet fixed. 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.