Replace the per-channel Reinhard display transform with a parameterized
soft clip T_p(x) = tanh(x^p)^(1/p), default softclip p=2, exposed through
--tone-map and --tone-map-p. Keep --tone-map reinhard bit-compatible with
the previous x/(1+x) curve for existing images and reject combining it
with an explicit --tone-map-p.
Route the primary image and the mesh overlay through the same
ToneMapSettings; the linear HDR FITS writer stays pre-tone-map. Add a
focused optics-linked tone-map test target, CLI success/error coverage,
and document the display operator versus the Moffat effective PSF.
--draw-mesh no longer modifies the primary render. The clean HDR FITS and
tone-mapped image are written first, then the final image-plane mesh is
overlaid in place on the already-consumed HDR buffer and saved as a
<stem>_mesh sibling. This applies uniformly to single-frame, movie-frame,
and imported lens-map renders, with derived paths validated before catalog,
spacetime, and render initialization.
Dummy PSF backends still write nothing and report ignoring --draw-mesh. The
reference-image target now uses the configured image extension so the
ENABLE_PNG=0 test path passes, and the CLI tests cover clean-main identity,
sibling naming, PATH_MAX overflow, and zero-tolerance HDR comparison.
README, README.zh-CN, and usage.md describe the new naming; the mesh reference
asset is renamed to match.
Add the production-density 4K Galactic-center comparison to the 2026-09-25 benchmark record, including the per-image error decomposition, and refine the fast-mode positioning in usage.md, the design document, and README.
- Document that nearest/bilinear deposit accuracy is set by the deposit mode and N rather than output resolution, and that the still-frame error is dominated by a small number of resolved bright cores while the flux-dominant faint texture is much better than the global relative L2.
- Add the temporal-coherence caveat: nearest deposition jumps by 1/N output pixel per axis across supersampled-cell boundaries, so fast mode is not qualified as a temporally coherent movie path; bilinear removes the centroid jump but broadens the profile.
- Add scripts/fast_mode_error_decomposition.py, which ranks the largest |fast-base| RGB samples and partitions the error by a disjoint base-value range.
Add an optional CPU preview path that deposits each point-source image as a
supersampled delta and resolves the whole frame with one global Moffat
convolution plus an N x N box average, instead of splatting a per-event PSF.
- optics: FastPsfAccumulator builds the pixel-area-integral kernel of the
target Moffat at the supersampled scale (width N*alpha, same beta). The
1/N^2 box average then reproduces the final pixel-area integral, so the
requested FWHM and beta are preserved without renormalisation. Deposits are
per-cell atomic adds; resolve accumulates into the caller's HDR buffer.
- frame: fast branch in frame_splat_catalog with one shared supersampled
buffer and a single resolve per frame; the accumulator is reused across
movie frames and built from the map dimensions on lens-map import.
- main: --fast-mode, --fast-supersample N (1..8, default 2) and
--fast-deposit nearest|bilinear (default nearest). CPU-only and rejected in
the HIP/dummy backends; --psf-min-y still applies per event while
--max-cache-psf-flux does not.
- The deposition scheme was chosen by scripts/fast_mode_deposit_error.py:
nearest keeps the PSF shape exactly with <= 0.5/N px position quantization;
bilinear keeps the exact centroid but broadens FWHM and beta. Recorded in
benchmarks/fast_mode_deposit_2026-09-18.md.
- tests/test_frame.c covers fast nearest vs the direct evaluator at the snapped
centre, flux conservation, bilinear centroid, min-Y discard, frame plumbing,
and HDR accumulation onto a non-zero background.
- benchmarks/fast_mode_cpu_2026-09-18.md records a ~10x speedup on the 2MASS
galactic-centre field with small tone-mapped differences.
Replace the artifact-affected Schwarzschild image with the corrected 4K render. Link both READMEs to the paired CPU/HIP benchmark and clarify that this run had no PSF wing clipping or direct fallbacks.
Cooperate across 32 lanes per PSF and use two completion-protected staging slots with complete batch timing. Restore coarse OpenMP event production while serializing shared GPU submissions and direct fallback boundaries.
Add bounded benchmarks, streaming and renderer regressions, and preserve validation evidence and ownership documentation.
Integrate timelike geodesics and Fermi-Walker tetrads in ingoing Kerr-Schild coordinates, sampled at a configurable proper-time cadence.
Add movie-track-samples to preserve CSV events as frames. Document usage and singularity guards, and cover analytic orbits, transport convergence, sampling, and CSV rendering.