* Viewer exposure on the full float range of 32 bpc frames (#2797)
32 bpc viewer frames on the desktop are rendered without the HDR step (skip_hdr_step,
#2916) and kept as half floats in the RAM preview. A display pass on egui-wgpu's device
turns each frame into one RGBA8 texture with mips per viewer, in this order: decode,
exposure in linear light, Compand / Tone Map, encode, display colour, Show Channel,
rounding. Before, exposure was an 8-bit lookup applied after tone mapping, clamping and
the display conversion, so -2 EV could not bring values above 1.0 back.
- engine: viewer::DisplayPass describes the pass as data; its pixel() is the CPU
fallback (no device) and the shader's reference. It replaces exposure_lut /
display_transform. FrameEncoding records a frame's curve and the HDR step it still
needs. 32 bpc snapshots are taken without the HDR step; snapshot_rgba8 applies it.
- ui-egui: FrameImage::CpuF16 (half crate, F16C at run time), byte accounting at 8 bytes
a pixel in the cache and the prefetch estimates; display_gpu.rs + display_gpu.wgsl;
main viewer, snapshot and passive viewers draw through the pass; the 8-bit image other
panels read is made on demand with the HDR step; the Info panel shows float values.
- Half-float frames are not written to the disk cache yet.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* Viewer display pass: f16 disk cache entries, window-device gating, review fixes
- Disk cache: half-float frame entries (format byte in the entry header, byte planes +
LZ4); 8-bit entries keep format 0 and stay valid. 32 bpc viewer frames are written and
read again, and the timeline's disk bar sees them. A damaged half-float entry is
deleted.
- The display pass runs on the window's egui-wgpu device, with or without the GPU
compositor (still building, failed, GL fallback). Its pipelines are made inside error
scopes; a backend that rejects them gets the CPU pass instead of a blank viewer.
- A new LUT of the same size (another ICC profile, Preserve RGB, another display) runs
the pass again.
- f32 to f16: one pass per L1-sized block, the NaN / infinity fix-up on the bits, no
fill of the buffer (4K: 4.7 ms, as the 8-bit conversion).
- Mips of odd-sized levels include the last column / row; the snapshot's half floats
and texture go with the snapshot; no placeholder texture ids; u64 size checks.
- Tests: LUT profiles and negative values against the shader, Bake reruns, the passive
viewer's colour, f16 disk round trips; exact comparisons allow 1 LSB on software
rasterizers. Docs: the display pass and the f16 disk entries in architecture.md.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* Viewer f16 disk-cache test: temp dir removed on failure too, wait for the queued disk write
Review points: the test's directory was only removed by its last statement
(now tempfile::TempDir), and the frame is released before its disk write is
queued, so flush() could return early (now waits for the entry).
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
* Viewer: oversized half-float frames use the CPU display pass, so exposure/HDR come before the averaging down
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
* Viewer: fmt and a debug assert for the half-float upload path
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
* Disk cache: persist_missing also writes half-float frames
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
* Passive viewer: oversized half-float frames take the CPU display pass instead of leaving a stale texture
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
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Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
