Revert "explorer: fix halo cutoff over terrain (disableDepthTestDistance)" (#181)#183
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rdhyee merged 1 commit intoisamplesorg:mainfrom May 9, 2026
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…t on points (isamplesorg#181)" This reverts commit d681758.
This was referenced May 9, 2026
explorer: halo crescents / disappearing dots over hilly terrain (root cause not yet identified)
#185
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…terrain (closes #185) (#198) Cluster and sample point primitives are placed at altitude=0 (the WGS84 ellipsoid surface). With Cesium world terrain enabled, terrain mesh in hilly regions (Troodos in Cyprus, hill country around Birmingham AL, etc.) rises hundreds to thousands of meters above ellipsoid — so points at altitude=0 are physically *underground* in those regions and get depth-culled by Cesium's standard per-pixel depth test. The fix is one new property at each of the three .add() call sites: disableDepthTestDistance: POINT_DEPTH_TEST_DISTANCE // 2.0e6 = 2,000 km Bypass scope: only when the camera is closer than 2,000 km, which covers every realistic interactive altitude (point mode <120 km, res8 cluster up to ~300 km, res6 up to ~3,000 km — the upper end is technically outside the bypass but at that altitude dots are tiny anyway). Why bounded (2.0e6) and not POSITIVE_INFINITY: PR #181 used Infinity and caused back-side-of-globe primitive bleed-through plus broke pickability (was reverted via #183). A 2,000 km bound preserves globe-ellipsoid occlusion at long range while bypassing terrain occlusion at every interactive zoom. Hypothesis source: Codex review of #185 identified sea-level placement as the most likely root cause. Confirmed experimentally by runtime- patching the live deploy: T0 baseline (no fix) Cyprus interior: ~0 dots T1 swap to EllipsoidTerrainProvider minor improvement T2 raise primitives to height=5000m significant improvement T3 disableDepthTestDistance: 2.0e6 (this PR) significant, equivalent to T2, no back-side bleed Closes #185. Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Reverts #181 (
d681758).Reported behavior:${\textsf{terrible}}$ — disabling depth test on point primitives caused regressions worse than the original halo crescents. Rolling back so prod returns to post-#180 state while we have Codex review d681758 and propose a corrected fix.
Original issue (still open): halos added in #180 expose terrain depth-test occlusion as crescents on hilly land, and at close zoom the dots vanish entirely.
Next steps:
d681758to identify a fix that doesn't regress whatever this just regressedRefs #178, #180.
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