The seam-floor purple flicker was NOT a draw z-fight. The in-engine
[seam-*] probe (ACDREAM_PROBE_SEAMDRAW - built because RenderDoc cannot
capture this pipeline: it hides GL_ARB_bindless_texture and the
mandatory-modern startup gate throws; AMD GPU rules out Nsight) killed
every double-draw suspect: ONE shell instance per seam cell at the
lifted z, no floor-coincident entity (portal entities sit at z=-12.05),
zero portal depth fans in the sealed Hub. What it caught instead: the
corridor floor's applied light set flipping wholesale with the flood.
Root cause: c500912b scoped BuildPointLightSnapshot by the per-frame
portal flood, on the research doc's gloss of CEnvCell::visible_cell_table
as "the portal-flood visible set". The named decomp refutes the gloss:
add_visible_cell (0x0052de40) DBObj-LOADS absent cells and inserts them;
a cell activation adds itself + its whole dat visible-cell list
(0x0052e228/0x0052e24a); entries leave only via the flush machinery.
It is the RESIDENT-cell registry - gaze can never remove a cell.
add_dynamic_lights (0x0052d410) walks the WHOLE table per frame
(caller 0x00452d30), and insert_light (0x0054d1b0) caps the pool by
distance to Render::player_pos (0x0054d1dd). Retail's pool is a function
of player position only. Ours followed the camera: turning changed the
flood (probe: 8..41 cells across one turn), the six intensity-100
under-room portal purples entered/left the pool, and the wedge blinked.
Fix: BuildPointLightSnapshot(playerWorldPos) collects ALL registered
(=resident) lit lights; over cap keeps dynamics FIRST (retail's separate
7-slot dynamic pool never competes with statics) then nearest-the-player;
the RebuildScopedLights callback is deleted. Live-verified with the probe:
full-circle turn, flood churning 8..41, the floor set held the same 8
identities on every post-spawn frame. The purple wedge SHAPE stays - it
is cdb-proven retail-faithful.
Residual deviation (AP-85 rewritten): single 128 pool vs retail's
7-dynamic/40-static degrade-scaled dual pools - the Hub now shows
7 purples + viewer where retail's cdb showed 4 + viewer + fixture slots;
if the gate reads the wedge as too purple, the A7 dual-pool cap is the
faithful trim.
Pins: PointSnapshot_HubScaleLightCount_ObjectSelectionIsCameraInvariant
(rewritten to the corrected model),
PointSnapshot_OverCap_DynamicsNeverEvictedByNearerStatics,
PointSnapshot_OverCap_KeepsNearestThePlayer,
PointSnapshot_ResidentCollection_CellTagDoesNotFilter.
Suites: Core 2599+2skip / App 726+2skip / UI 425 / Net 385.
The [seam-*] probes stay until the visual gate passes, then strip.
Correction banner added to 2026-07-06-a7-per-cell-lighting-pseudocode.md;
outcome banner on the z-fight handoff; ISSUES #176 updated.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Port retail's per-frame light collection: the point-light pool is built from ONLY the
currently-visible cells' lights, matching CObjCell::add_*_to_global_lights
(0x0052b350/0x0052b390) walked over CEnvCell::visible_cell_table (0x0052d410) — not a
flat world-space set capped at 128-nearest-camera.
- LightSource.CellId (retail insert_light arg6 -> RenderLight +0x6c); tagged at both
registration sites from entity.ParentCellId (live weenie fixtures + dat EnvCell statics).
- LightManager.BuildPointLightSnapshot(camPos, visibleCells): a light joins the pool iff
CellId==0 (viewer/global) or its cell is in the flood. 128 cap kept as a now-non-biting
backstop (retail's is 40 static + 7 dynamic, 0x0081ec94/8).
- Threaded via RetailPViewDrawContext.RebuildScopedLights, invoked in DrawInside after the
flood resolves prepareCells and before the draws (renderers select from the same
in-place-rebuilt PointSnapshot; EnvCellRenderer clears its per-cell cache each pass).
- [indoor-light] probe (ACDREAM_PROBE_INDOOR_LIGHT=1) dumps the scoped-pool SET COMPOSITION.
Un-skips LightManagerTests.PointSnapshot_HubScaleLightCount_ObjectSelectionIsCameraInvariant.
CORRECTION: the handoff called the camera-cap the "confirmed" #176/#177 mechanism. The probe
PROVES scoping works (291 Hub fixtures -> pool of 1-9, ~285 through-floor lights dropped/frame,
CellIds match the flood), but the user's VISUAL GATE showed BOTH symptoms unchanged. So pool
composition is NOT the cause. #176 real cause = an over-bright purple point light
(intensity=100, color 0.784,0,0.784 -- from [light-detail]); #177 = a portal-visibility miss
(stairs not drawn looking back). Both stay OPEN. This change is retail-faithful and retires the
camera-eviction latent bug; kept as such, not as the symptom fix. Register AP-85 corrected;
ISSUES #176/#177 re-diagnosed; render digest banner updated.
Decomp: insert_light 0x0054d1b0, minimize_object_lighting 0x0054d480, calc_point_light
0x0059c8b0; pseudocode docs/research/2026-07-06-a7-per-cell-lighting-pseudocode.md.
Suites green: Core 2595 + 2 skip, App 719 + 2 skip.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>