The writing-plans decomp pass read FixCellList (433407) -> AdjustCellView (433741)
-> ClipPortals(update_count) + AddViewToPortals, proving retail RE-PROCESSES a
grown-after-drawn cell. So the approved "enqueue-once / no re-process" approach is
wrong (it would break Build_ViewGrowthAfterDoneCell for the right reason — that test
is actually retail-faithful).
Corrected approach (user chose the faithful moderate port over an epsilon-dedup
band-aid): KEEP re-processing on growth, but BOUND it the way retail does — each
view slice processed once (monotonic update_count watermark) and redundant
reciprocal back-contributions clip to EMPTY (OtherPortalClip -> no copy_view -> no
new slice), so the reciprocal/drift loop can't churn. acdream churns because its
reciprocal yields a drifted non-empty sliver, bounded only by the
MaxReprocessPerCell=16 hack. Remove the cap; bound structurally.
Scope unchanged: PortalVisibilityBuilder only; no rooting/camera/clip-math-rewrite/
seal change. One open precision (exact line where acdream's sliver becomes
non-empty — float-drift-dependent on real geometry) deferred to the plan's first
task: instrument PortalVisibilityBuilder (per-pop re-pop count + reciprocal-clip
in/out + grew), capture at the doorway, pin it, THEN fix.
Spec updated in place with a REVISION banner; superseded enqueue-once body retained
for the audit trail.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>