T5 reported doors/interiors visible through terrain hills and through
nearer buildings, always in aperture-shaped regions. Root cause, decomp-
settled: retail's DrawPortalPolyInternal (Ghidra 0x0059bc90) draws the
punch with DEPTHTEST_ALWAYS + per-vertex far-Z (0.99999899, maxZ1 bit0)
- it UNCONDITIONALLY stomps any occluder depth at aperture pixels.
Retail is safe only because its outdoor pass is painter's-ordered
far->near: anything nearer (hills, closer houses) draws AFTER the punch
and re-covers it. Our z-buffered MDI frame has no such global order
(one terrain pass + one shells pass), so the faithful GL-state port of
the punch was unsafe by construction - the far house's aperture punch
erased the near house's wall depth / the hill's depth, and the interior
+ door entities (dynamics drawn last) painted through.
Fix - the z-buffer-correct equivalent of the painter's-order guarantee:
punch only where the aperture polygon itself is VISIBLE.
PortalDepthMaskRenderer's punch path is now two passes:
A) stencil-mark: aperture fan at its (slightly biased) true depth,
depth LEQUAL, no depth write -> stencil=1 where the aperture wins
against everything drawn so far (terrain + all shells precede
DrawExitPortalMasks in the frame, so the buffer holds the real
occluders);
B) far-Z punch with depth ALWAYS, stencil-gated EQUAL 1, zeroing the
stencil as it goes (self-cleaning; no frame-level stencil state).
The mark bias (0.0005 NDC ~ 6 cm at 5 m) keeps #108's case covered:
terrain hugging the door plane still punches; a hill or another house
meters nearer no longer does. The SEAL path (interior roots) stays
retail-verbatim single-pass - it runs right after the gated full depth
clear, so there is nothing nearer to stomp.
Also: WindowOptions now requests 8 stencil bits explicitly (was the
GLFW platform default), and PortalDepthMaskRenderer's stale "RESERVED -
not wired" banner is corrected (T1 wired it via
DrawRetailPViewPortalDepthWrite).
Acceptance rides the focused post-T5 re-gate (downhill door check +
behind-house openings check + #108 cellar stays clean).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Visual gate (2026-06-11) on the seal+punch build, then on the punch-reverted
build, isolated the truth:
- With the punch wired: #108 (cellar grass-sweep) gone BUT the player/NPCs
go transparent by exactly their overlap with any doorway viewed from
outside (the far-Z punch erases the depth of dynamic objects standing in
the aperture, so the interior paints over them).
- With ONLY the punch reverted (seal+full-clear kept): characters render
correctly AND #108 is BACK.
The punch is wired for OUTDOOR roots + the look-in path ONLY; it never runs
on a clean interior (cellar) frame. For it to have suppressed #108, the
cellar-transition frames must render through the OUTDOOR root -> the player
is being classified OUTDOOR mid-cellar (the known #112/#106 cellar
membership ping-pong). So:
- #108 is a MEMBERSHIP bug (render is downstream of membership); the punch
was MASKING it, harmfully. Re-attributed to the membership track.
- The interior-root SEAL addresses a case that is NOT #108 (confirmed: #108
isn't an interior-root frame), so it has no verified visible effect yet.
Per no-workarounds + verify-before-layering: reverted ALL of BR-2's depth
machinery (seal, punch, the per-slice->full-clear swap) to the pre-BR-2
baseline (restored from 6cba950). The phantom-site probe (6cba950) is kept.
PortalDepthMaskRenderer.cs is KEPT as a RESERVED, unwired primitive (it is
verified-correct; the depth discipline will be rebuilt during BR-3 with
dynamics-after-interior ordering, where it can be verified against the
shell-chop deletion).
What survives from this session's execution: BR-1 (already-equivalent,
695eca2) stands. #108 moves to membership. BR-2 to be re-approached under
BR-3 with correct ordering. No net production behavior change vs 6cba950.
Suites: build green, App 226 green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Ports the seal half of retail's invisible portal depth writes
(D3DPolyRender::DrawPortalPolyInternal, Ghidra 0x0059bc90; dispatched by
PView::DrawCells loop 1, Ghidra 0x005a4840 pc:432783-432786):
- NEW PortalDepthMaskRenderer: draws a portal polygon as a color-masked
triangle fan, depth-test ALWAYS + depth-write ON, at the polygon's TRUE
projected depth (retail maxZ2 seal) or forced to far-z 0.99999988
(retail maxZ1 punch - the constant from 0x0059bc90's tail; punch wiring
lands in BR-2 commit 2). Where retail software-clips the fan against
the installed view (polyClipFinish), we apply the SAME slice region via
gl_ClipDistance from the slice's <=8 clip-space half-planes. GL state
fully self-contained (set -> draw -> restore, no early-outs).
- DrawExitPortalMasks is now WIRED in production (was a null-callback
no-op since birth): for interior roots, every visible cell's portals
with OtherCellId==0xFFFF get their world-space polygon sealed per view
slice, far-to-near, after the landscape slices.
- ClearDepthSlice (per-slice scissored AABB clear - wrong shape, wrong
scope, no seal after it) is REPLACED by ClearDepthForInterior: ONE
full-buffer depth clear between the outside stage and the interior
stage, gated on any outside slice having drawn (retail's
portalsDrawnCount gate semantics staged as an open question, marked
inline). DepthMask(true) asserted at the clear site (c4df241 lesson).
Outdoor roots: no clear, no seals (interiors must depth-test against
terrain until the commit-2 punch).
Closes the mechanism behind #108 (outdoor grass sweeping across the
upstairs door opening - terrain depth seen through the doorway is now
re-stamped at the door plane so farther interior geometry z-fails inside
the aperture). Visual gate: BR-2/BR-3 batched checklist (cellar doorway
+ cottage wall + tower stairs near/far).
Suites: build green, App 226 green, Core 1398 + 4 pre-existing #99-era
failures + 1 skip.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
