New CellTransit static class ports retail's portal-graph cell traversal:
- FindTransitCellsSphere — indoor portal-neighbour walk
- AddAllOutsideCells — outdoor 24m grid expansion
- FindCellList — top-level driver (BFS through portals;
PointInsideCellBsp for final containment)
PhysicsEngine.ResolveOutdoorCellId renamed to ResolveCellId. Body
rewritten: indoor seeds delegate to CellTransit.FindCellList (portal-
graph BFS + BSP containment test); outdoor seeds keep the landblock
terrain grid lookup from the original implementation (preserving the
L.2e prefix-preservation fix). Signature extended with sphereRadius
parameter (needed by the sphere-vs-portal-plane test). Three call
sites updated (PhysicsEngine x2, TransitionTypes x1).
BSPQuery.PointInsideCellBsp retyped from PhysicsBSPNode? to CellBSPNode?
— the function operates on the cell-BSP tree (CellPhysics.CellBSP.Root
is a CellBSPNode). The previous PhysicsBSPNode typing was dead code, so
retype is safe.
Deletes the Phase D ResolveOutdoorCellIdTests.cs file. New ResolveCellIdTests
covers the equivalent contracts (fallback zero, outdoor seed with no
landblock).
Outdoor->indoor entry (check_building_transit) is stubbed pending the
BuildingPhysics infrastructure landing in the next commit.
Spec: docs/superpowers/specs/2026-05-19-indoor-portal-cell-tracking-design.md
Plan: docs/superpowers/plans/2026-05-19-indoor-portal-cell-tracking.md
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
