Add error-controlled DP5(4) integration and trusted first-crossing localization, including non-monotonic energy thresholds and representable-time stepping.
Preserve adaptive state and independent step/time retry grants across RayPool, refinement and movie scheduling. Expose numerical controls, record actual persistent-sample costs, and add v3 lens-map provenance with legacy v2 RK4 import.
Use DP54 by default and select an 8M Schwarzschild maximum step from bounded scans and a two-run 4K comparison. Retain the conservative minimum-step guard and document critical-ray and backend capability limits. Archive self-contained benchmark inputs and raw output; keep fixed RK4 HDR references explicit.
Validation: make -B -j4 BUILD_TYPE=Debug test passed; explicit RK4 HDR references have zero differences. Bounded convergence checks, benchmark reproduction, Release build and focused reviews passed. No numerical-relativity backend is added.
--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.
Check spherical area weight sums against a fixed 1e-8 tolerance and normalize accepted weights before interpolation. Skip invalid images in both catalog paths.
Add a thin-triangle regression for both parities, document the measured tolerance margin, and refresh HDR fixtures with strict comparisons restored.
wyj