Phase A4 (multi-cell BSP iteration) ships in three commits (e6369e2,
493c5e5, 691493e — with revert 3add110 + reapply during visual
verification that proved A4 is not the cause of the issue surfaced).
1139 + 8 baseline maintained. 10 new unit tests pass. Wires retail's
CTransition::check_other_cells (acclient_2013_pseudo_c.txt:272717-272798)
into Transition.FindEnvCollisions.
Visual verification at the Holtburg inn vestibule surfaced a separate,
pre-existing M2 blocker (filed as #90): CellId ping-pongs between
outdoor 0xA9B40022 and indoor 0xA9B40164 on every wall push-back
because the push-back exits the indoor CellBSP volume, causing the
resolver to flip back to outdoor and bypass walls on outdoor ticks.
Indoor BSP results (Collided/Adjusted/Slid all firing) prove walls ARE
detected when the player is indoor; the aggregate "walls walk through"
appearance comes from CellId classification instability, not from
collision detection.
Bug reproduces fully with A4 reverted (launch-revert2.log captured 18
cell-id flips between 0xA9B40022 ↔ 0xA9B40164, 11 inside=True
building-transit events, 61 indoor-bsp queries firing the full
result distribution). A4 is correct and tested but dormant in
practice until #90 is fixed.
Updates:
- docs/research/2026-05-20-phase-a4-shipped-cell-pingpong-finding.md (new)
- docs/plans/2026-04-11-roadmap.md (A4 shipped row added)
- CLAUDE.md (Indoor walking Phase A4 paragraph + next-step pointer
to #90 with retail oracle anchor at acclient_2013_pseudo_c.txt:308742-308783)
- docs/ISSUES.md (#90 filed, HIGH severity, M2-blocker)
- docs/research/2026-05-21-open-items-pickup-prompt.md (landscape
table updated — A4 closed, #90 promoted to top blocker)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
