Facility Hub corridor repro (probe + dat evidence, both mechanisms
pinned):
1. PortalSide portal polygons live IN CellStruct.PhysicsPolygons and
acdream collides with them as plain solid geometry. Cell
0x8A02016E's portals to 0x011E (polys 1/3/5, flags=PortalSide) are
present in the physics set while every ExactMatch portal in the
same cell is absent — the cell's rotation maps those portal planes
to the world -X wall the player hit mid-corridor
(launch-175-verify2.log:42858, n=(-1,0,0)). Retail must honor the
portal side; oracle grep required before fixing.
2. After the single seam hit, the body-persisted SlidingNormal
projects every subsequent forward offset to exactly zero in
AdjustOffset - the step aborts BEFORE any collision test can
update state (ok=False hit=no, zero advance), an absorbing wedge
escaped only by strafing ("push through on the side"). The #116
slide-response family: retail re-derives slide state per frame
(get_object_info pc:279992).
Inspection fixture: Issue137CorridorSeamInspectionTests (dumps
physics-vs-portal polygon membership for the two corridor cells).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>