caf61d41a539903f8d806e4b40d450c827203726
A thumbnail comes from the file's embedded preview, which is the camera's idea of the photograph and knows nothing about what has been done to it since. So a frame could be cropped, turned upright and pulled two stops back, and the grid would go on showing the original — making the library, where a photographer spends most of their time, the one view in which an edit is invisible. The render is the framed output, not the sensor: `output_size` is what a crop, a quarter turn, a flip and a straighten all act on, so a thumbnail taken from the raw frame would be the right pixels in the wrong shape and still the wrong way up. It is the same path an export takes, at a size the store wants rather than at full resolution, and always sRGB — this is a JPEG in a shard that syncs between devices and is drawn as a cell, not a file anyone is finishing. Both size classes are replaced. The store keys on the class, so refreshing only the one the grid happens to be drawing leaves the other holding the unedited preview, and a zoom across the boundary would show the edit undoing itself. Each is rendered rather than downscaled from the larger, which would be a second and worse resampler than the GPU has already applied. It runs on the way out of develop, after the sidecar write is queued and never instead of it — the edit is what must not be lost, and a render that failed must not take the save down with it. Two cases are worth the work: an edit made in this sitting, which `can-undo` records even when it ends back at neutral, and an image opened with an edit already in its sidecar and left untouched, whose cached thumbnail has never shown that edit at all. A neutral image nobody touched fails both and costs nothing. Not covered: a batch paste onto a selection, which deliberately never opens a session — there is no rendered frame to take a thumbnail from, and downloading forty RAWs to make forty is exactly what that path exists to avoid.
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.
Releases
20
DarkRoom 0.24.0
Latest
Languages
Rust
86.1%
Slint
10.3%
Python
1.1%
Shell
1%
WGSL
0.9%
Other
0.6%