78e3e6b846771e9344e032b79afd4b32719505ee
Decode through display, on the GPU: black/white normalisation, Bayer demosaic, camera colour transform, and the first seven adjustment operations — white balance, exposure, highlights/shadows, blacks/whites, brilliance, vibrance, saturation. Composable shaders. Each operation contributes a WGSL fragment rather than owning a pass, and dr-pipeline fuses the *active* ones into a single compute shader. One texture read and one write per frame regardless of how many adjustments are in play, while the operations stay independent in Rust — adding one is a new file, with no central shader to edit. An operation at neutral settings contributes no code, no uniform and no branch. Uniforms are prefixed per operation so two may both declare `amount`; helpers dedupe by name from a single source of truth. Pipelines cache on a structure hash covering the op-set and its order but not the values, so dragging a slider uploads uniforms and reuses the compiled pipeline. Measured on a 24 MP CR2: 0.60 ms re-render, one pipeline compiled across ten slider positions. The UI is generated, not written. EditGraph::capabilities() reports parameters with their kinds, ranges, defaults and current values; the panel builds one control per entry chosen by ParamKind. No file in ui/ names an operation, and dr-pipeline has no wgpu dependency, so codegen is testable without a device (ARCH §6.5a). Three defects found against real files, each silent: - rawler 0.7.2's `xyz_to_cam` is all zeros — deprecated and no longer populated. The live matrices are in `color_matrix`, keyed by illuminant. Reading the old field yields no colour transform at all. - `cam_to_xyz_normalized()` returns all NaN on any Bayer sensor: it divides each of four rows by its own sum, and the unused fourth (emerald) row sums to zero. Inverting the 3x3 ourselves avoids it. `wb_coeffs[3]` is NaN for the same reason and is normalised at decode. - As-shot white balance reached the uniform block but no shader read it, so the first render of a real CR2 came out violently green. Green photosites collect roughly twice the signal of red and blue. Now applied unconditionally before any operation, with tests on ordering. Demosaic is Malvar-He-Cutler rather than bilinear: gradient-corrected interpolation at one 5x5 neighbourhood per pixel, where bilinear leaves visible zippering on any high-contrast edge at 1:1. Two of the four packed CFA constants were wrong on the first attempt, so all four layouts are asserted to reconstruct the same colour. Crop origins at odd coordinates re-phase the pattern; without that, red and blue swap. X-Trans reports GpuError::UnsupportedCfa rather than approximating with the Bayer path, which would look like a corrupt file. 206 tests, including GPU tests proving every operation and the full seven-operation chain generate compilable WGSL. Known gaps: the display path still reads back to the CPU each frame, which ARCH §6.1 forbids and AC-8 asserts against — it is gated behind the `readback` feature and waits on spike S1 wiring Slint's texture import. Curve shapes are a first draft and want tuning against real photographs. 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.
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%