First Holtburg-doorway capture showed all 191 [resolve-bldg] entries
labeled "n/a (cylinder)" — including hits attributed to the building
0xA9B47900 which [entity-source] confirmed was registered as type=BSP.
The label was a probe bug, not a real cylinder route.
Root cause: BSPQuery's grounded-path (Path 5) returns early via
`StepSphereUp(transition, worldNormal, engine)` when no step is already
in progress. The slice-1 side-channel write at line 1546 came AFTER
that early return, so it never fired for the dominant grounded-player
case. Compounding: StepSphereUp recurses into ResolveWithTransition →
FindObjCollisions, whose per-entity `LastBspHitPoly = null` clear
wiped any earlier write before the outer attribution emitter read it.
Fix:
1. BSPQuery Path 5: move LastBspHitPoly write to the top of
`if (hit0 || hitPoly0 != null)` blocks (both foot- and head-sphere),
BEFORE the StepSphereUp early return. Recursion-safe — the inner
resolve's BSP writes will overwrite with the inner entity's poly,
but for the dominant case (same wall hit on both outer and inner)
that's still the correct attribution.
2. TransitionTypes.FindObjCollisions: drop the per-entity clear of
LastBspHitPoly. With BSPQuery now writing at hit-detection time
instead of response-computation time, the side-channel value is
reliable without per-iteration zeroing.
3. TransitionTypes [resolve-bldg] emission: key the "n/a (cylinder)"
label on `obj.CollisionType` directly, not on LastBspHitPoly being
null. A BSP entity with a null poly now logs "n/a (BSP path —
side-channel not written, missing BSPQuery wire site)" so any
future BSPQuery path that's missing the wire is visible in the
trace rather than being silently mis-labeled.
Verified: build green, the 2 slice-1 tests still pass, 8 pre-existing
failures unchanged.
Spec: docs/superpowers/specs/2026-05-13-l2d-cbuildingobj-collision-design.md
First capture (showing the label bug): launch-l2d-slice1.log lines
12086-12120 (representative [resolve-bldg] entries for obj=0xA9B47900).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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