islaApocalypse-v2/Core/Scripts/TerrainDetailPass.cs.uid
beezm 35b4818e9e Phase 2a: the faithful redistribution curve, re-measured against v2's own output
Ports the reference's v5 height curve and shelf-detail passes onto Phase 1's shape
and re-calibrates them against this repo's actual pass-1 distribution. This is the
BASELINE the reshape gets judged against, not the reshape.

Core (engine-free, D-060):
- WorldScale — THE vertical yardstick. One metres/raw number (251), replacing the
  prototype's three duplicate M_PER_UNIT constants and ~20 bare literals. The
  chunk-height coupling it had there is recorded as a DEFERRED vault decision, not
  inherited. RawFromMetres divides, matching the reference bit-for-bit.
- HeightCurve — the 7 bands, the frozen corner-fix blends, the per-seed spike
  normalization, the 24-corner monotonicity sweep that throws and refuses.
  Identity at and below sea, which everything downstream rests on.
- CurveKnots / CurveAnchors — input knots (measured percentiles) and output anchors
  (storm ladder) split apart and both made parameters, so the anchors are A/B-able
  without editing source. The reference's shipped knots are kept beside the measured
  ones as the fidelity yardstick.
- TerrainDetailPass — micro-relief skin plus the shelf-edge KNOT warp (which slides
  K3/K4/K5, not height — that is what keeps monotonicity structural). The crater
  exclusion is ported and inert until the carve lands.

Tools:
- Shaping — pass 2a, producing the two height fields. classify is bit-for-bit the
  raw pass-1 field; render is curved and detailed. Aliased when the curve is off,
  as the reference did. Pass1Result is left immutable so the oracle can compare.
- LandHistogram — the calibration engine AND the diagnostic. The reference shipped
  six knot literals and threw the measuring instrument away; this rebuilds it.
- ShapingOracle + CurveBaselineTool — four automatic checks before anything is
  looked at, and the batch that runs them.

Measured, not assumed:
- Knots re-measured over a 6-seed / 12.8M-sample pool. They differ from the
  reference's by at most 5.6 m of world height, against a 44.7 m per-seed spread —
  the pass-1 port is faithful.
- Oracle all pass, including pass 1 bit-identical to Phase 1's own .f32 dump.
- Band shares land on 60/13/10/5/8/3/1 to 0.00 pp.
- Knots hold across map size: the 8K delta (5.8 m) sits inside seed noise.

The finding the histograms deliver: 83% of land ends below 100 m and 96% below
220 m, with the median column at 13 m. That is the share targets doing exactly what
they say, not a bug — and it is the developer's call, which is why nothing here
reshapes it and the palette was deliberately left mis-fitted rather than recalibrated
to disguise it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DCWNaDZPfTiAy3meGNGgqt
2026-08-20 01:38:10 -04:00

1 line
20 B
Text