Attached cdb to the live 2013 retail client at the Holtburg doorway + read the decomp.
The indoor flap is a STRUCTURAL divergence, settled by measurement (not inference):
- Retail has ONE render path: DrawInside(viewer_cell) every frame. NO inside/outside
branch (RenderNormalMode's outside branch is dead code; is_player_outside only gates
sky/lighting). "Entering a building" is not a render event — only the camera sweep
resolving a different viewer_cell. Same path before/after threshold -> no seam.
- Retail's eye JITTERS ~36um at rest yet membership is stable -> robustness is
STRUCTURAL: many small per-building floods (~7/frame, ~2 cells each, via terrain BSP
-> DrawPortal -> ConstructView(CBldPortal)), not one giant knife-edge flood.
- Our 3 divergences: (D1) invented inside/outside branch (GameWindow.cs:7498,
clipRoot = viewerRoot ?? _outdoorNode :7396); (D2) synthetic _outdoorNode; (D3) one
unified flood.
DECISION (user-approved): Option A — rip out branch + outdoor node, root always at the
real viewer_cell, one DrawInside, per-building rendering. Phased, conformance-tested,
visual-gated.
REFUTED by measurement (do not retry): bounded-propagation/churn (maxPop=1, 0/63k
reciprocals empty); byte-stable eye (retail's jitters ~36um — rest-snap cd974b2 failed +
regressed, reverted 9b1857a).
Lands the canonical exhaustive handoff for a FRESH session
(docs/research/2026-06-08-full-retail-render-port-OPTION-A-handoff.md), the CLAUDE.md
READ-THIS-FIRST banner, and reusable cdb apparatus. No project code changed; working tree
at the known-good baseline.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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