Per-step subagent-driven plan for the render half: T0 test-hygiene baseline,
Stage 3 render-root unification (root at CellGraph.CurrCell + seen_outside, drop
the FindCameraCell grace-frame fallback), Stage 4 PView seal (sky/landscape inside
the portal-clip bracket + conditional doorway Z-clear = no blue-hole; EnvCellRenderer
GL_BLEND verify), Stage 5 entity/particle cell-clip. Key reframe from grounding the
plan in the actual code: the PView infra (PortalVisibilityBuilder BFS + OutsideView,
ClipFrame, EnvCellRenderer GL_BLEND fix, WbDrawDispatcher cell gate) ALREADY EXISTS and
the A8 stencil split is already gone — so the render half is wire-and-fill-gaps, not a
from-scratch port. Execution policy: no intermediate user gates, single final visual
verification, full suite green at verification.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>