From df5eba1ba65d6b57067a1d77e025a774f9c370d2 Mon Sep 17 00:00:00 2001 From: Brendan Collins Date: Fri, 10 Apr 2026 21:52:31 -0700 Subject: [PATCH] Record accuracy sweep round 2: hillshade, terrain, perlin clean Audited three highest-priority never-inspected modules for numerical accuracy issues. All passed with no bugs found: - hillshade: Horn's method matches GDAL, all 4 backends consistent - terrain: Perlin/Worley/ridged noise correct, dask chunk boundaries produce bit-identical results vs numpy - perlin: improved Perlin noise (quintic fade) verified, continuous at cell boundaries, backends consistent --- .claude/accuracy-sweep-state.json | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/.claude/accuracy-sweep-state.json b/.claude/accuracy-sweep-state.json index f4b62063..22fb9916 100644 --- a/.claude/accuracy-sweep-state.json +++ b/.claude/accuracy-sweep-state.json @@ -4,6 +4,9 @@ "focal": { "last_inspected": "2026-03-30T13:00:00Z", "issue": 1092 }, "multispectral": { "last_inspected": "2026-03-30T14:00:00Z", "issue": 1094 }, "proximity": { "last_inspected": "2026-03-30T15:00:00Z", "issue": null, "notes": "Direction >= boundary fragile but works due to truncated constant. Float32 truncation is design choice. No wrong-results bugs found." }, - "curvature": { "last_inspected": "2026-03-30T15:00:00Z", "issue": null, "notes": "Formula matches ArcGIS reference. Backends consistent. No issues found." } + "curvature": { "last_inspected": "2026-03-30T15:00:00Z", "issue": null, "notes": "Formula matches ArcGIS reference. Backends consistent. No issues found." }, + "hillshade": { "last_inspected": "2026-04-10T12:00:00Z", "issue": null, "notes": "Horn's method correct. All backends consistent. NaN propagation correct. float32 adequate for [0,1] output." }, + "terrain": { "last_inspected": "2026-04-10T12:00:00Z", "issue": null, "notes": "Perlin/Worley/ridged noise correct. Dask chunk boundaries produce bit-identical results. No precision issues." }, + "perlin": { "last_inspected": "2026-04-10T12:00:00Z", "issue": null, "notes": "Improved Perlin noise implementation correct. Fade/gradient functions verified. Backend-consistent. Continuous at cell boundaries." } } }