3 Commits

Include renames

Author	SHA1	Message	Date
dtourolleandClaude Opus 5	56978fdf35	Clear the clippy warnings that were failing CI before this branch ... 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>	2026-08-25 22:35:02 +02:00
dtourolleandClaude Opus 5	3b5952769b	Emit floats an f32 can hold, and drop the format! that formats nothing ... 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>	2026-08-25 22:28:14 +02:00
dtourolleandClaude Opus 5	b6a95e1965	Simulate a film stock from its measurements, not from someone's grade ... FR-DEV-3f asks for look emulation and proposes HaldCLUT import to inherit the free film-simulation ecosystem. This takes the other road for the stocks where the measurements exist: run the physics. A stock here is its manufacturer's own datasheet -- spectral sensitivity, characteristic curves, dye densities. Light exposes three emulsion layers, the layers develop to densities, the densities are dyes that absorb, and what is left is what reaches the eye. A colour negative comes out orange and upside down because that is what a colour negative is; it becomes a photograph when a paper profile prints it, with the enlarger's filtration solved rather than dialled. What that buys over a LUT is that the parameters stay physical. Opening up a stop moves the picture along the film's real characteristic curve, shoulder and all, instead of scaling a number baked at one exposure. The data cost runs the other way too: a stock is 17 kB of published measurements where one HaldCLUT is 800 kB of one person's grade. It looks like it needs a spectral integration per pixel. It does not, and that is the whole design: - Exposure is a 3x3 matrix. The reconstructed scene spectrum is linear in the sRGB triple, so the integral collapses into nine numbers, exactly -- no approximation. - The characteristic curve is three 1D functions, sampled exactly. - Everything after that -- dye absorption, the print through the negative, the paper, the viewing illuminant, the adaptation -- takes exactly three numbers in, so it bakes into one 32^3 lookup. Per pixel: a matrix multiply, three curve taps, one fetch. Splitting the curve out of the 3D lookup rather than baking one LUT over exposure is measured, not assumed: the curve carries the sharp shape and the dye mixing is smooth, so folding them together would need three times the resolution for the same error. At 32^3 the worst error is 0.003 in linear sRGB, under one 8-bit code value, and a test says so. No wgpu dependency, deliberately, and the same isolation argument dr-lens makes: the model is plain f32 with a documented layout, so every property worth asserting is asserted on the CPU. Binding it to a texture is dr-gpu's job and is not done here yet. The expected values in tests/ came from a Python prototype running against a different colour-science stack. Agreement to three decimals is evidence about the model rather than about one implementation of it -- a transposed matrix or a mispasted observer row would pass every unit test and fail that one. Profiles are converted from spektrafilm by Andrea Volpato, CC BY-SA 4.0. The converter is in the tree and runnable, so what was changed from upstream is auditable rather than taken on trust; profiles/CHANGELOG.txt records it, including the one deliberate deviation -- Mallett & Yuksel's 1 kB basis instead of Hanatos's 4 MB table, which costs accuracy at the gamut edge and saves four megabytes. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>	2026-08-25 14:44:54 +02:00