Tracking the ROADMAP.md D4 defect as an issue.
From ~50–100 km camera altitude, smooth concentric arcs (iso-distance contours around the nadir) appear in AP-LUT-driven haze over the planet surface. Clean at ground level; clean above blendEndKm (pure raymarch).
Known facts from bisection (full notes in ROADMAP.md § D4):
- Bands live in the AP-LUT branch:
hazeMode=raymarch is clean; blendEndKm directly modulates visibility; TLUT/MS resolution has no effect.
- Tried and reverted (4827ff0 → 97e3003): ±half-texel W dither + 64-sample jittered LUT build — bands persisted AND added noise. So the W-interpolation-kink hypothesis is wrong or incomplete.
- Next suspects: 32×32 screen-space XY interpolation (froxel rays diverge strongly at altitude; the underground-froxel correction rewrites ray dir/tMax per voxel, so neighbouring XY texels store integrals of genuinely different rays), or banding baked into stored values by the correction itself.
- Discriminator before any fix attempt:
?debug=ap-alpha screenshot at a banding altitude vs ?debug=rm-alpha.
- Possibly related: reference scales AP samples per slice (see the per-slice SPP issue) and caps coverage at 128 km vs our 1024 km in demo 05.
- Workaround shipping today:
hazeMode=raymarch at altitude, or lower blendEndKm so the auto ramp hands off earlier.
🤖 Generated with Claude Code
Tracking the ROADMAP.md D4 defect as an issue.
From ~50–100 km camera altitude, smooth concentric arcs (iso-distance contours around the nadir) appear in AP-LUT-driven haze over the planet surface. Clean at ground level; clean above
blendEndKm(pure raymarch).Known facts from bisection (full notes in ROADMAP.md § D4):
hazeMode=raymarchis clean;blendEndKmdirectly modulates visibility; TLUT/MS resolution has no effect.?debug=ap-alphascreenshot at a banding altitude vs?debug=rm-alpha.hazeMode=raymarchat altitude, or lowerblendEndKmso the auto ramp hands off earlier.🤖 Generated with Claude Code