Adds ACDREAM_PROBE_BUILDING — a read-only per-shadow-entry probe that
captures full BSP collision evidence whenever TransitionTypes.FindObjCollisions
attributes a hit (via the existing L.2a slice 3 chain). One multi-line
[resolve-bldg] entry per attributed hit: partIdx, hasPhys, bspR vs
vAabbR, world-space entOrigin_lb, and the actual hit polygon's vertices
in both object-local and world space.
Paired with a one-time [entity-source] line at every ShadowObjects.Register
call site in GameWindow so entityId from a probe line is greppable to its
WorldEntity source within a single log file.
Plumbing: BSPQuery writes the resolved hit polygon to a new
PhysicsDiagnostics.LastBspHitPoly side-channel at the 5 SetCollisionNormal
sites in Paths 5/6 + CollideWithPt. TransitionTypes clears that field
before each shadow-entry dispatch and reads it back at the L.2a slice 3
attribution site to emit the probe line.
Spec component 4 originally described an out ResolvedPolygon? parameter
on BSPQuery.FindCollisions; the static side-channel achieves the same
observable behavior without plumbing through BSPQuery's recursive private
methods. Deviation noted in PhysicsDiagnostics.LastBspHitPoly's XML doc.
Reframes the plan-of-record's L.2d sub-direction paragraph: the 2026-05-12
handoff proposed porting CBuildingObj + per-cell walkability, but ACE
BuildingObj.cs:39-52 + named-retail acclient_2013_pseudo_c.txt:701260
show find_building_collisions is one BSP test on Parts[0]. Per-cell
walkability belongs to L.2e, not L.2d. L.2d slice 1 is the diagnostic;
slice 2 is the actual fix scoped from slice 1's evidence (one of three
hypotheses: wrong BSP loaded / over-registered parts / BSPQuery flaw).
Tests: 2 synthetic unit tests in PhysicsDiagnosticsTests.cs pin the
static API contract that the BSPQuery → side-channel → TransitionTypes
emission chain depends on. The multi-line line format itself is verified
by acceptance criterion 2 (live Holtburg-doorway capture) — covering it
here would require a heavy PhysicsEngine + Transition fixture for a
diagnostic-only emission.
Verified: dotnet build green; the 2 new tests pass; the 8 pre-existing
test failures listed in the L.2a handoff (MotionInterpreter GetMaxSpeed_*,
PositionManager.ComputeOffset_BothActive_Combined,
PlayerMovementController.Update_ForwardInput_*, Dispatcher.W_held_*,
BSPStepUpTests.{D4,C3}) remain failing — none introduced by this slice.
Spec: docs/superpowers/specs/2026-05-13-l2d-cbuildingobj-collision-design.md
Conformance anchors:
- acclient_2013_pseudo_c.txt:701260 (CBuildingObj::find_building_collisions)
- acclient_2013_pseudo_c.txt:323725 (BSPTREE::find_collisions)
- ACE references/ACE/Source/ACE.Server/Physics/Common/BuildingObj.cs:39-52
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>