The A6.P4 port, fused into one installment per the BR-2 half-port lesson
(registration and query are co-dependent: flood-registering shells under
the old radial query would re-open #98 through the vestibule).
REGISTRATION (ShadowObjectRegistry rewritten):
- Register/RegisterMultiPart/UpdatePosition compute the cell set via
CellTransit.BuildShadowCellSet (the C2 find_cell_list flood) seeded by
the entity's m_position cell id; the private 24m XY-grid rectangle and
its single-landblock clamp are deleted. Flood spheres follow retail's
CylSphere rule (base point + cyl radius, cap 10; BSP bounding-sphere
fallback - Ghidra 0x0052b9f0). Statics flood with the do_not_load
prune; dynamics (server spawns, isStatic:false) without.
- Keep-when-empty (SetPositionInternal num_cells gate, pc:283540): a
failed flood leaves the previous registration in place.
- RefloodLandblock: streaming-race hook re-runs the flood when a
landblock's cells hydrate (retail init_objects -> recalc_cross_cells,
Ghidra 0x0052b420/0x00515a30); wired at GameWindow's hydration tail.
- GameWindow sites pass the server position's full cell id as the seed
(spawn + UpdatePosition); the five static sites pass ParentCellId.
BUILDING CHANNEL (CSortCell.building shape):
- Building SHELLS are not shadow objects in retail (only caller of
find_building_collisions is CSortCell::find_collisions 0x005340aa;
one building per origin landcell, init_buildings 0x0052fd80 verified
verbatim + ACE cross-ref). IsBuildingShell entities skip the registry;
Transition.FindBuildingCollisions runs the shell part-0 BSP off
cache.GetBuilding(cellId) with bldg_check set around it
(find_building_collisions 0x006b5300), CollidedWithEnvironment on
non-Contact non-OK. BuildingPhysics.ModelId = pre-resolved part-0
GfxObj (0x02 Setups resolved at the CacheBuilding site).
- Placement/ethereal weakening: BSPQuery Path 1 passes center_solid=0
when BldgCheck && HitsInteriorCell (BSPTREE::find_collisions 0x0053a82e
+ placement_insert 0x005399d8) so doorway crossings don't hard-fail
against shell solids. SpherePath gains both retail fields;
HitsInteriorCell is rebuilt at every cell-array build
(build_cell_array reset 0x00509ef2 + find_cell_list/check_building_
transit set sites).
QUERY (retail per-cell order, transitional_insert 0x0050b6f0):
- TransitionalInsert per attempt: env -> building (LandCell only) ->
objects on the PRIMARY cell, then on OK the check_other_cells pass
(env -> building -> objects per OTHER overlapped cell) + the
carried-cell advance - the advance now happens AFTER all per-cell
object passes (the WF1 ordering divergence), with Adjusted/Slid
feeding the retry exactly like retail's OK_TS case.
- FindObjCollisionsInCell = CObjCell::find_obj_collisions (0x0052b750):
iterate ONLY the asked cell's list. DELETED: the radial 9-landblock
sweep, the +5m query pad, the b3ce505 indoor-primary gate, and the
isViewer exemption (the camera is bounded by interior cell-BSP env
collision - retail's own channel; CameraCornerSealReplayTests pins it
against real dat, and the new building-channel camera test pins the
outdoor stop).
TESTS: Core 1416/0/2 (was 1398 + 4 pre-existing #99-era fails + 1 skip),
App 225, UI 420, Net 294 - all green.
- 3 of the 4 #99-era reds flipped green as designed: the door apparatus
(Apparatus_Grounded_50cmOffCenter_FrontApproach_Blocks) and tick-13558
(indoor walkthrough) now assert the door BLOCKS; tick-22760 pins the
outdoor blocking invariant.
- The 4th (BSPStepUp D4) + 22760's lateral-slide delta are NOT cell-set
problems (probes prove the door is found + BSP-only dispatched;
BR-7 left both byte-identical) - filed as issue #116 (slide-response
family), D4 skipped with the issue reference.
- FindEnvCollisionsMultiCellTests migrated to the public entry (the A4
multi-cell halt now lives at the retail call site).
- New registry pins: per-cell query surface, outdoor-footprint-never-
indoor (#98 architectural), door-outdoor-cell membership, reflood.
- CameraCollisionIndoorTests rewritten against the building channel
(the isViewer-exemption pins died with the exemption).
Closes#99 (doors block both ways via registration-time cell membership
+ the straddle-spanning player cell array). #97 likely closed (the +5m
radial pad that produced phantom-collision candidates is gone) - verify
at T5. #98 stays closed ARCHITECTURALLY (outdoor footprints structurally
cannot reach interior cells; the cellar harness stays green).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
After the primary cell's BSP returns OK, query every other cell the
foot-sphere overlaps via CellTransit.FindCellSet + Transition.CheckOtherCells.
Closes the Holtburg inn vestibule wall walk-through: the vestibule
(cell 0xA9B40164) has only 4 BSP polys; walls live in the adjacent
interior cell (0xA9B40157). Without A4 the adjacent cell's BSP was
never queried.
End-to-end test reduces the real Holtburg bug to a minimal synthetic
two-cell fixture: empty vestibule BSP + interior cell with the
existing BSPStepUpFixtures.TallWall (the same fixture B2 uses to
prove a grounded mover can't scale a 5m wall). Pre-A4: returns OK
(walks through). Post-A4: returns Slid (the wall halts the
transition).
FindEnvCollisions visibility tightened from private → internal so
the integration test can call it directly without going through
FindTransitionalPosition's sub-step iteration.
Retail oracle: acclient_2013_pseudo_c.txt:272717-272798
(CTransition::check_other_cells).
Spec: docs/superpowers/specs/2026-05-20-phase-a4-multi-cell-bsp-design.md
Plan: docs/superpowers/plans/2026-05-20-phase-a4-multi-cell-bsp.md
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
