OPSTACK-PROGRESS gets the measured entry: every number the run produced, what each one settles, and
the single open warning. OPSTACK-PLAN's status header goes from UNVERIFIED to BUILT AND GREEN.
OPSTACK-HANDOFF is rewritten end to end. It no longer describes a transition in progress but a
completed one, and it leads with the two things a cold context needs: the Underwater 0%-coverage
warning (with the truncation-vs-floor finding behind it, and the reminder that a green bit-identity
over solid rock is not evidence), and the one task everything else now waits on -- making
FRoomGraphSource::EffectOverBox answer spatially.
It also carries forward the two debts that must be paid BEFORE that lands rather than after: box
bounds computed from strate params can be too optimistic once a per-room op raises them, and AUDIT
C2 is confirmed but unfixed on the switch path.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
UsesOperatorStackForChunk now returns true for both, so the archetype switch has a complete
operator-stack twin: per-strate opt-in, every archetype equivalence-tested bit for bit against its
original function.
This changes nothing by itself. The flag still requires bUseOperatorStack ticked on a strate asset,
which is Jahni's call and was deliberately NOT done. What HAS changed is that the flag is no longer
a no-op anywhere: ticking it on any strate now really switches that strate onto the stack.
Not done, and it is the next real prize: ClassifyTile still uses hand-written guards and does not
consume ClassifyBox. That is where measured tile-skipping becomes frames.
DOCS
- CODEMAP 3.2d: ported list 6 of 8 -> 8 of 8; the BuildTunnelNetworkStack row rewritten (19 ops, one
builder for two archetypes); six new rows for the detail modifiers, each carrying the thing a
reader would otherwise have to rediscover -- roughness reads STRATE params, terrace re-queries the
SDF, the cliff's comment disagrees with its code, columns have no strate parameter at all, and
LocalParams() is the override whose EffectOverBox is too optimistic on a strate with an op pool.
Also corrected the stale "never compare the two paths" line: C10 is closed and all eight
equivalence tests compare bit for bit.
- CODEMAP 3.3 UsesOperatorStackForChunk row: same list, plus the warning that the flag is now a real
switch rather than a harmless tick.
- OPSTACK-PLAN: status header and the Phase 2 order both updated; the three-stage TunnelNetwork
breakdown and the calls-not-transcribes rule recorded there rather than only in the code.
- OPSTACK-PROGRESS: the closing entry for this unattended run -- every commit in order, the five
original-code findings ported as-is, the two decisions that are not reversible by taste, the
ClassifyBox optimism C1 introduced and that must be fixed before ClassifyTile consumes it, what
breaks first per group, and the likely compile-error spots.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
6 of 8 archetypes ported. This one starts from VOID and FILLS where the
other four start from ROCK and CARVE, which is what it was worth doing:
neither end of the pile needed a new operator, only the opposite sign.
FConstantRockSource -> FConstantFieldSource(+/-Base) AllSolid <-> AllAir
FSdfCarveOp -> FSdfConvertOp(Sign = +/-1) carve <-> fill
FSdfRoughnessMod 4th archetype, unchanged
Only the island blob source is new. Multiplying by +/-1 is exact in
IEEE-754, so the three already-green ports are bit-for-bit untouched.
ClassifyBox can return AllAir for the first time in the plugin, and an
island strate is by construction mostly empty — the test counts AllSolid
and AllAir separately so an aggregate cannot hide whether that fired.
Two bounds that would have been holes if assumed rather than derived:
the island bound is one-sided (a hairline thread of matter hangs below
each island down its axis, so only the TOP may reject), and the domain
warp displaces X and Y independently, so the pad needs WarpAmp*sqrt(2).
Also: AUDIT C1 was NOT closed. The 2026-07-27 sweep matched `SeedF * K`
and this archetype's warp spells it `(float)S * K`, so one site survived
— at seed 2e9 the warp flattens and every island snaps back to a perfect
circle. Fixed in both paths in one pass so the equivalence test stays a
valid oracle. Expect island silhouettes to change at large seeds.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The port that tests the thesis rather than the fidelity. Previous ports asked whether
the decomposition reproduces the original; this one asks whether operators actually
get reused across archetypes, which is section 2.5's claim and the only reason to do
this refactor instead of tidying the switch.
ConstantRock, SdfRoughness and SdfCarve are Maze's, reused without a line changed.
In the switch, GetMazeDensity and GetVerticalShaftDensity are two ~100-line functions
with nothing visibly in common; as operators they are the same three ops with a
different source and different tuning (freq 0.1 vs 0.12, window rough+4 vs R+rough+2).
New: FShaftFieldSource (infinite cylinders + hash-gated connectors into the SDF
channel) and FShaftLedgeMod (banded shelves on the +X/+Y half so the shaft stays
climbable).
Deviation from section 6, stated: it suggested splitting the source so the XY-pure
cylinder half could get an exact box verdict. Kept as one op because the connectors
derive from the same 3x3 roll and the ledge mod needs the shaft list anyway, so
splitting means rolling twice or sharing a cache between two ops. Forfeited: the exact
verdict on the cylinder half. Kept: a conservative EffectOverBox testing circles and
connector reach.
FShaftLedgeMod gates on the POST-roughness Sdf as the stack left it; re-deriving it
would use the pre-roughness value and shift every ledge. Reading the channel rather
than recomputing is what the two-channel sample is for.
Compile fix: FCells was declared below the functions returning it. Member bodies are
deferred, return types are not.
Ported: Maze, FlatPlain, CrystalChamber, SurfaceWorld (biomes included),
VerticalShafts — 5 of 8.
UNVERIFIED: not compiled past the FCells fix.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Jahni: "I do not need your work to be identical or near identical to what I had
before, only having it 99.99% at worst reproducible if two people share the same
seed, since everyone rebuilds it on multiplayer."
Recorded as OPSTACK-PLAN 2.6.1, superseding 2.6's "recognisably the same place".
Consequences, each recorded where it will be found:
- C10 closed permanently rather than parked: it measures old-path vs new-path
agreement and the two never coexist in a shipped world.
- The equivalence tests keep their value as PORT-CORRECTNESS checks, not fidelity
checks. Isosurface hard-fail stays; ULP grading is diagnostic only.
- C9 promoted to top open risk. "Two people share a seed" is exactly what /fp:fast
weakens across toolchains, and a Linux dedicated server against Windows clients
compiles the density path under opposite float models. FPSemantics = Precise is
the fix and the IWYU debt now blocks something that matters.
- C1 unblocked: it was deferred only because it re-rolls the world's noise.
Then, doing C1's arithmetic before applying its documented one-liner: THE FIX IS
WRONG. It bounds SeedF but keeps the * 97.7 multiplier, so the coordinate term
still reaches 1.6e6 where the ULP is 0.19 — 9.5x the ~0.02/voxel step. It would
have left the bug live for mid-range seeds while closing the ticket.
The real fix deletes the multipliers: they only decorrelate the ~40 noise sites,
which is a hashing job. VoxelHash::SeedOffset(Seed, Site) gives a site-salted,
bounded, final-units offset. Bounding SeedF alone would also funnel every seed
through 16384 offsets shared by all sites; per-site salting requires a collision at
all ~40 sites instead.
The op stack has already inherited the bug via FSlabVoidSource, so it must land in
both paths at once — and every further port copies it again.
Docs only; the C1 fix is not written.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Jahni closed OPSTACK-DECOMPOSITION 3.1: the slab noise Z term was not
intentional character. Phase 1 also closed — the visual A/B on Maze passed.
Two changes, deliberately together, kept attributable by the test:
1. Design: GetSlabDensity's floor and ceiling noise lose their Z terms. A floor
height no longer depends on the altitude you sample it from. The ceiling keeps
its + 3000.0f, which is a decorrelation offset, not a Z term. The world
re-tunes once — a different slice of the noise field, not a worse one.
2. Refactor: the now-XY-pure function ports to FSlabVoidSource + FGridColumnMod
plus the three structural ops. BuildSlabStack has NO branch on archetype
because GetSlabDensity never had one — CrystalChamber is FlatPlain with a
bigger CeilingRoughness. 8 archetypes -> 7.
SlabEquivalence compares against the reference AS IT IS NOW and runs the whole
battery on both slots, so green means the port is a pure refactor and any visual
delta is attributable to the Z-term removal alone. The attribution comes from the
test, not from splitting it across two builds.
The payoff 3.1 was actually about: FSlabVoidSource::ClassifyBox is exact and needs
no sampling. FBM is contractually [-1,1], so both surfaces live in Z bands with
known bounds — a tile below the floor band is provably solid, a tile between the
bands provably air. ClassifyTile proves zero tiles for these archetypes today.
FGridColumnMod answers Identity when no column reaches the box, which is what lets
the source's AllAir verdict survive the fold.
UNVERIFIED: not compiled.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Jahni's call to pin it and move on, and the right one -- six builds spent and the
information stopped being worth the cost.
The final run closed it as far as it can be: SDFs identical everywhere (counted
unconditionally, 0 differ), yet two character-identical carve implementations in
the SAME translation unit fed a provably identical input differ by 1 ULP on
126/5000. That is only possible if they compile to different instruction
sequences, which /fp:fast permits based on surrounding context with no single
isolable axis. Hypothesis 3 was right about the mechanism and wrong about every
clean variable proposed for it, which is why four well-designed isolation tests
came back negative.
AUDIT C10 records the observation, what is proven (SDF bit-exact 126/126, zero
isosurface crossings), the five refuted hypotheses in a table so nobody repeats
them at a build each, why the settling experiment is blocked (shared-PCH / IWYU
debt), and the rule that actually matters: never run both density paths in one
world and never compare them for equality. That is NOT a client-desync risk --
within a binary the field is proven bit-pure and every peer runs the same path --
the cross-platform concern is C9, which stands on its own.
Corrected OPSTACK-PLAN 2.6 and C9: my earlier "/fp:fast across translation units"
explanation was measurably wrong and is removed rather than softened.
MazeEquivalence keeps the permanent value (equivalence with ULP grading,
window-invariance, box-verdict brute force) and drops the verbatim copy,
three-way, bisect, inlining and constness experiments.
Phase 1 closed: Maze decomposes into 7 ops, SDF bit-exact, 0 isosurface
crossings, window-invariant, and 23 of 60 tiles proved uniform where ClassifyTile
proves zero.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The bisect settled it. The difference survives every stage removal down to
"corridors + carve ONLY", which is character-for-character transcribed code, so
it is not in anything the decomposition added.
Cause, read out of the engine rather than assumed (VCToolChain.cs):
case FPSemanticsMode.Default: // Default is imprecise FP semantics.
case FPSemanticsMode.Imprecise: Arguments.Add("/fp:fast"); break;
with UBT's own doc: "the compiler is allowed to transform math expressions in
ways that might result in differently rounded results". Identical source in two
translation units may reassociate differently, worth ~1 ULP. It shows up on
exactly the ~2% of samples inside the SDF blend shell, where Blend - Sdf
catastrophically cancels; outside it Carve is exactly 0 or 1 and both agree.
So MazeEquivalence now grades what it can actually assert:
- hard fail : any isosurface crossing (geometry moves)
- info : differences at ULP scale (the unavoidable floor)
- warn : anything larger, which IS port drift, and runs the bisect
A test that warns on every port would get ignored by the port that matters.
Recorded in OPSTACK-PLAN 2.6, and as AUDIT C9 for the part that outlives this
refactor: ARCHITECTURE 9.1's "every peer regenerates identically" holds only
between bit-identical binaries under /fp:fast. Fine for one build on one
platform; a real desync source for a Linux server plus Windows clients both
regenerating authoritative geometry. The FPSemantics::Precise knob exists but
must not be turned speculatively -- it blocks the vectorisation T2.a was chasing,
on the hot loop, for an unmeasured cost.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Phase 0.5 and the Phase 1 skeleton marked WRITTEN / NOT COMPILED (not "done" --
the gates are not met until the tests actually run). Section 8 independent fixes
2, 5 and 6 ticked. Section 9 "Resume here" now says BUILD.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
AUDIT P1: every markdown design doc except CODEMAP.md was untracked, so
ARCHITECTURE / AUDIT / OPSTACK-PLAN / fable-idea / REVIEW_FINDINGS lived
only on disk. Replaces the single !CODEMAP.md exception with !*.md.
Also makes OPSTACK-PROGRESS.md commits actually record something, which
the unattended crash-safety discipline depends on.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Fr0zka