The decisive probe between the two surviving suspects from the 2026-06-09
building-flood-merge handoff (docs/research/2026-06-09-flap-outdoor-fullworld-
building-flood-merge-handoff.md section 1), gated by ACDREAM_PROBE_CLIPROUTE=1,
all print-on-change:
- [clip-route] (RetailPViewRenderer.DrawLandscapeThroughOutsideView): the
outside slice slot + NDC AABB + planes, the CellIdToSlot routing table, the
region-SSBO bytes DECODED at the routed slot, and the terrain-UBO head —
captured after SetTerrainClip + UploadClipFrame + SetClipRouting, i.e.
exactly what the landscape draws consume. Pins/refutes suspect (b) and the
slot-repack half of suspect (a).
- [clip-route-disp] (WbDrawDispatcher.Draw, routed draws only): per-slot
instance histogram exactly as staged for binding=3 plus the count of
entities dropped by ResolveSlotForFrame CULL. Pins/refutes the
instance-routing half of suspect (a).
- [clip-route-scis] (GameWindow.DrawRetailPViewLandscapeSlice): the ACTUAL GL
scissor enable + box read back right after BeginDoorwayScissor — the whole
landscape pass (sky + terrain + outdoor entities + player) draws inside this
box, so a doorway-sized box here IS the full-world kill by construction.
Code-reading findings recorded while building the probe: the landscape pass is
scissored to slice.NdcAabb end-to-end (GameWindow.cs DrawRetailPViewLandscapeSlice),
and ResolveEntitySlot CULLs server entities with null ParentCellId while routing
is active — both now directly observable under the probe.
Throwaway apparatus — strip once §4 ships.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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