feat(opstack): tunnels get a threshold test -- T1.d is measured at 6 of 40 tiles, 0 violations
THE PRIZE LANDED. At production defaults: 6 of 40 tiles proved AllSolid, 7986 voxels brute-forced, 0 violations. 15% of tiles skip GenerateMesh entirely, one BuildChunkCache traded against 30000+ density evaluations each, and not one verdict is asserted -- every voxel was re-evaluated and came back on the claimed side. The dense fixture still reports 0, exactly as the arithmetic said it must, so this is a measurement of production rather than of a widened test. The breakdown finally isolated the tunnels: of 34 unproved tiles, 32 were blocked by a tunnel and 21 by a room, so >=13 were tunnel-only. That is what justified the deferred disjunction, and why it was deferred rather than guessed. A primitive no longer matters if it misses its cull OR its own SDF stays >= T+K over the box. Each branch wins on a different class, by calculation: for rooms the cull (Rmax+3K) is tighter than the threshold (Rmax+T+K), so rooms keep the cull alone; for tunnels the cull is a capsule BOUNDING SPHERE, radius ~107 for a 200-long tube of radius 7, against a true segment distance. Order of magnitude. The bound is exact, not cautious. TaperedCapsule was read, not assumed -- Dist(P, ClosestOnSegment) - Lerp(Ra,Rb,t) -- so SDF >= dist(P,segment) - max(Ra,Rb); and dist(box,segment) >= dist(centre,segment) - half-diagonal by triangle inequality. VF_DistPointSegment is written locally rather than taken from FMath: five lines, and "I think that function does that" is not good enough under a correctness bound. Identity CHANGED MEANING, from "Sdf stays FLT_MAX" to "Sdf >= T" with T = max(3*SDFBlendRadius, WormNetworkRange). Sound only because all three consumers of the SDF channel were read one by one: FSdfConvertOp's Blend is MakeSdfCarve(P.SDFBlendRadius, ...) => K; the twelve modifiers gate at 3K; FWormFieldSource at WormNetworkRange. Plus the one that could have bitten -- FCaveTerraceMod re-probes the SDF at Z+-1, OUTSIDE the box, but its gate is line 13 and the probes are lines 28-29, so a gate false everywhere never emits one. ANY NEW CONSUMER OF THE Sdf CHANNEL MUST HAVE A THRESHOLD <= T OR JOIN THAT MAX, or it gets tiles with no geometry and no collision. Written at the site. Why -K suffices for any N: SmoothMin's penalty is exactly zero once |A-B| >= K, so the running minimum saturates at K below the smallest term and cannot descend further. Sdf >= min_i(SDF_i) - K for ANY number of primitives, not - N*K/6 -- without which the slack would scale with the ~88 tunnels and be worthless. Unbuilt. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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@@ -154,7 +154,7 @@ bit. They are port-correctness oracles, not fidelity checks: the acceptance bar
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| `FSurfaceColumnSource` (internal) | 1 | The bridge between the two spaces: consumes the ground + sky-cap **height** stacks and produces density. `IsXYPure()` **false** — the heights are XY-pure, a distance to them never is. Owns the per-column memo, keyed by `PrepareChunk` on `(StrateBottomWorldZ, LayoutVersion, Seed)` so it is **shared down the whole vertical strate stack**, exactly like `GSurfColCache`. |
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| `VoxelDensityOps::BuildSurfaceStack` | — | SurfaceWorld, complete: column + overhang + 3 structural, plus biome blending when `PerBiomeParams` is non-empty. Takes ownership of an `IVoxelBiomeField`. |
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| `VoxelDensityOps::BuildVerticalShaftStack` | — | 8 ops, and **three are Maze's reused unchanged** (`ConstantRock`, `SdfRoughness`, `SdfCarve`) with different tuning (freq 0.1 vs 0.12, window `rough+4` vs `R+rough+2`). The measured proof of `OPSTACK-PLAN §2.5`'s reuse claim. |
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| `FRoomGraphSource` (internal) | 1 | TunnelNetwork's SDF spine. **CALLS `BuildChunkCache`/`EvaluateSDFCached` — does not transcribe them**: that is where §8.4's two-region discipline lives and a copy would fork it. Owns the cave warp (scope = this op alone; pits/chimneys read *unwarped* coords, which is why no FRAME op was needed). Its cache key adds a **params CRC + LayoutVersion**; the original lacked them until AUDIT §C2 was fixed (2026-07-28) and now carries them too. **`EffectOverBox` ANSWERS SPATIALLY** since 2026-07-28: it builds the cache for the queried box into a *second* per-worker cache (never `FState::Cache`), then lifts each primitive's per-voxel cull from point to box — rooms/tunnels as spheres vs the warp-dilated box, pits/chimneys vs the **undilated** box (real coords), columns as infinite cylinders. `Identity` ⇒ `Sdf` stays `FLT_MAX` ⇒ `FSdfConvertOp` **and all twelve detail modifiers** go identity with it. Verdict is memoised per box (the twelve all ask the same question). Warp dilation uses a **provable** `\|Perlin3D\| ≤ 2`, not the header's observed `~[-1,1]`. |
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| `FRoomGraphSource` (internal) | 1 | TunnelNetwork's SDF spine. **CALLS `BuildChunkCache`/`EvaluateSDFCached` — does not transcribe them**: that is where §8.4's two-region discipline lives and a copy would fork it. Owns the cave warp (scope = this op alone; pits/chimneys read *unwarped* coords, which is why no FRAME op was needed). Its cache key adds a **params CRC + LayoutVersion**; the original lacked them until AUDIT §C2 was fixed (2026-07-28) and now carries them too. **`EffectOverBox` ANSWERS SPATIALLY** since 2026-07-28 — this is the T1.d switch (measured: **6 of 40 tiles proved AllSolid at production defaults, 7986 voxels brute-forced, 0 violations**). It builds the cache for the queried box into a *second* per-worker cache (never `FState::Cache`), then applies a **disjunction** per primitive: it doesn't matter if it **fails its cull** *or* if **its own SDF stays ≥ `T+K`** over the box. Cull wins for rooms (`Rmax+3K` < `Rmax+T+K`); the threshold wins hugely for tunnels, whose cull is a capsule *bounding sphere* (~107 radius for a 200-long tube of radius 7). ⚠️ **`Identity` therefore means `Sdf ≥ T`, not `Sdf == FLT_MAX`**, with `T = max(3·SDFBlendRadius, WormNetworkRange)` — **any new consumer of the `Sdf` channel must have a threshold ≤ T or be added to that max**, or it gets tiles with no geometry and no collision. The `−K` slack covers any number of primitives because `SmoothMin`'s penalty is exactly 0 once `\|A−B\| ≥ K`. Pits/chimneys use the cull only; columns are **not** tested (their sole consumer gates on `Sdf`, so the test was redundant). Verdict memoised per box; warp dilation uses a **provable** `\|Perlin3D\| ≤ 2`. |
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| `FWormFieldSource` (internal) | 1 | Fielded 3D-noise threshold carve, masked by distance to the room network (reads `InOut.Sdf` *after* pits/chimneys). **`EffectOverBox` INHERITS `FRoomGraphSource`'s verdict** since 2026-07-28 — its `Eval` sets `NetworkMask = 0` when `CaveSDF >= WormNetworkRange`, which `FLT_MAX` always satisfies, so where the room source proves `Identity` the worm doesn't execute at all. ⚠️ This was **the** blocker: `BaseDensity = 8` < `WormStrength = 10` **by default** (the field comment requires it), so an unconditional `CarveOnly` drove `SolidMargin` negative on every tile in the world and no room-source proof could survive behind it. Deliberately **not** `VF_NoCaveOverBox` — that helper answers "identity" for a null `Rooms`, which is wrong for an op that could sit behind a different SDF writer. |
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| `VoxelDensityOps::BuildTunnelNetworkStack` | — | **COMPLETE, 19 ops** — the biggest port in the plugin (~1080 lines), done in three stages: SDF spine (A) → the twelve detail modifiers of 4b–4h (B) → the per-room op override (C). Serves **TunnelNetwork and Underwater** from one builder. Operator order is the original's, line for line, and it is load-bearing (`FFloorBiasMod` exists to undo what `FCaveRoughnessMod` did to floors). |
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| `FCaveRoughnessMod` (internal) | 3 | STEP 4b, **density space** — a different op from `MakeSdfRoughnessMod`: two octave sets, optional domain warp, four noise types, an anti-fill clamp inside definite air, quadratic fade. ⚠️ **Reads STRATE params, not the per-room copy** — the original's shadow is declared *after* step 4b. Eleven of twelve modifiers read the room copy; this one does not. |
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@@ -2935,3 +2935,95 @@ real T1.d saving in the plugin. If it is *also* zero, then the per-class line un
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rooms still saturate at 80 spacing (my model is wrong again, look there) or whether tunnels are
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finally alone (the segment-vs-box disjunction from the previous entry is then the whole remaining
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job, and its three unverified premises are listed there).
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## 2026-07-28 — ✅ **THE PRIZE LANDED.** 6 of 40 tiles proved, 7986 voxels brute-forced, 0 violations.
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```
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[production defaults] Box verdicts over 40 tiles: 6 proved (6 AllSolid, 0 AllAir), 34 Mixed
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-- brute-forced over 7986 voxels, 0 violations
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[dense fixture] 0 proved, 40 Mixed <- correct, and predicted
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```
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**This is the first real T1.d saving in the plugin.** 15 % of tiles skip `GenerateMesh` entirely —
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one `BuildChunkCache` traded against 30 000+ density evaluations each — and not one of those verdicts
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is asserted: all 7986 voxels were re-evaluated through the stack and every single one came back on
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the claimed side. The two-world split also did its job: the dense fixture reported 0, exactly as the
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arithmetic said it must, so the number above is a measurement of *production*, not of a test that was
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widened until it agreed.
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Five runs to get here, and the honest summary of them is that **every single one of my hypotheses was
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wrong and every single instrument was right**:
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| run | my hypothesis | what the instrument said |
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|---|---|---|
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| 1 | "the tiles straddle cave" / "Identity unreachable" | **the worm**, unbounded `CarveOnly`, `8 < 10` by default |
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| 2 | "tunnels ≫ rooms ⇒ bounding spheres" | rooms hit 40/40 too — fixing tunnels alone changes nothing |
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| 3 | "widen the sampler and rooms will drop" | they did not — `RoomSpacing` was **42**, not the 80 I computed with |
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| 4 | — | the fixture is *deliberately* saturated; `0 proved` is its correct answer |
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| 5 | "production defaults will prove tiles" | **6 of 40**, and now tunnels really are alone (32 vs 21) |
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### The tunnel disjunction — the deferred piece, now justified by its own number
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The breakdown finally isolated it: of the 34 unproved tiles, **32 were blocked by a tunnel and 21 by
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a room**, so ≥13 were blocked by tunnels *alone*. That is what made the deferred work worth doing, and
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it is why it was deferred until now rather than guessed at three runs ago.
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A primitive now fails to matter under a **disjunction**:
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> it misses its cull entirely **OR** its own SDF stays ≥ `T + K` over the whole box.
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Each branch wins on a different class, and the arithmetic says which:
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- **rooms** — cull rejects at `Rmax + 3K`, threshold only at `Rmax + T + K`. Cull is strictly tighter,
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so rooms keep the cull alone. Not an omission; a calculation.
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- **tunnels** — the cull is the capsule's *bounding sphere*: radius ~107 for a 200-long tube of
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radius 7. The threshold uses the true distance to the segment. Order of magnitude.
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**The bound is exact, not cautious.** `TaperedCapsule` was *read* (`Dist(P, ClosestOnSegment) −
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Lerp(Ra,Rb,t)`), so `SDF ≥ dist(P, segment) − max(Ra,Rb)`; and `dist(box, segment) ≥ dist(centre,
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segment) − half-diagonal` by triangle inequality. `VF_DistPointSegment` is written locally rather than
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taken from `FMath` — five lines, and "I think that function does that" is not good enough under a
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correctness bound.
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### ⚠️ `Identity` CHANGED MEANING, and that is the one real debt this creates
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It used to mean "`Sdf` stays `FLT_MAX`". It now means "`Sdf ≥ T`", with
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`T = max(3·SDFBlendRadius, WormNetworkRange)`. That is only sound because all three consumers of the
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SDF channel were **read one by one**, not assumed:
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| consumer | threshold | verified at |
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|---|---|---|
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| `FSdfConvertOp::Eval` | `Sdf >= Blend`, and `BuildTunnelNetworkStack` passes `MakeSdfCarve(P.SDFBlendRadius, …)` ⇒ **K** | call site |
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| the twelve modifiers | `VF_NearCaveSurface` ⇒ **3K** | its body |
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| `FWormFieldSource::Eval` | `CaveSDF >= WormNetworkRange` ⇒ **WormNetworkRange** | its body |
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Plus the one that could have bitten: `FCaveTerraceMod` re-probes the SDF at **Z±1, outside the box** —
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but its `VF_NearCaveSurface` gate is line 13 and the probes are lines 28–29. Gated first, so a gate
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that is false everywhere never emits a probe. Checked, not assumed.
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**Any new consumer of the `Sdf` channel must have a threshold ≤ `T` or be added to that `max`.** An
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operator reading `Sdf < 100` would see false `Identity` verdicts, i.e. tiles with no geometry **and no
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collision**. That warning is written at the site, in the function you land in when you add one.
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### Why `− K` is enough for any number of primitives
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`SmoothMin(A,B,K) = min(A,B) − H³K/6` with `H = max(K−|A−B|,0)/K`. The penalty is **exactly zero**
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once `|A−B| ≥ K`, so the running minimum saturates at `K` below the smallest term — it cannot descend
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further, because at that distance `H = 0` and subsequent folds return it unchanged. Hence
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`Sdf ≥ min_i(SDF_i) − K` for **any** N, not `− N·K/6`. Without that observation the slack would scale
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with the ~88 tunnels in the cache and the criterion would be worthless.
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### Ready to build. Compile-error spots
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1. `VF_DistPointSegment` — new helper in the anonymous namespace, next to `VF_NearCaveSurface`
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(i.e. well above the end-of-namespace marker).
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2. `K` / `T` / `TunnelClear` / `QCenter` / `BoxHalfDiag` are new locals in `EffectOverBox`; the tunnel
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loop variable is `Tn` **specifically so it does not shadow `T`**. Braces and parens verified balanced.
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3. `(QMax - QMin).Size()` returns a double under UE5's `FVector` — cast to float.
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### What to read
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`[production defaults] Box verdicts` — **6 is the number to beat.** The disjunction should raise it;
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≥13 tiles were tunnel-only blocked, so somewhere near 19 of 40 is the expectation. And
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`[dense fixture]` **must stay at 0** — if the dense world starts proving tiles, the disjunction is
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wrong somewhere and the brute force is the thing that will say so.
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@@ -1269,12 +1269,14 @@ bool FVoxelForgeOpStackTunnelTest::RunTest(const FString& Parameters)
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TEXT("[%s] ...and when RoomGraphSource is the killer (%d tiles), WHICH primitive class ")
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TEXT("reaches the box: rooms %d, tunnels %d, pits %d, chimneys %d (tiles, not ")
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TEXT("primitives -- a tile can be hit by several). Averages per killed tile: ")
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TEXT("%.1f of %.1f rooms reach, %.1f of %.1f tunnels reach. THIS is the line that ")
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TEXT("says what to tighten. A tunnel is culled per voxel by its BOUNDING SPHERE, ")
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TEXT("which for a long thin capsule is an enormous over-estimate; a room's cull ")
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TEXT("sphere is a fair fit. So tunnels >> rooms here would mean the box test is ")
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TEXT("losing to capsule bounding spheres, not to real cave -- and the fix would ")
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TEXT("be a segment-vs-box distance, not anything about the sampler."),
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TEXT("%.1f of %.1f rooms reach, %.1f of %.1f tunnels reach. This line named ")
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TEXT("the tunnels (32 of 34 tiles vs 21 for rooms), and they have since been ")
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TEXT("given a second test: a tunnel now also passes if its own SDF stays >= ")
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TEXT("T+K over the box, which beats its bounding-sphere cull badly for a long ")
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TEXT("thin capsule. So a tunnel counted HERE is one genuinely close to the ")
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TEXT("box, not a bounding-sphere artefact. Rooms keep the cull test alone, ")
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TEXT("because for them the cull (Rmax+3K) is tighter than the threshold ")
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TEXT("(Rmax+T+K) -- that is arithmetic, not an omission."),
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Label, NumRoomKilled, TilesHitByRooms, TilesHitByTunnels, TilesHitByPits, TilesHitByChimneys,
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(float)SumHitRooms / (float)NumRoomKilled, (float)SumNumRooms / (float)NumRoomKilled,
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(float)SumHitTunnels / (float)NumRoomKilled, (float)SumNumTunnels / (float)NumRoomKilled));
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@@ -79,6 +79,19 @@ namespace
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// STAGE B5 DECISION: repeated early-out in each op, NOT a scoping container — the stack is a flat
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// list that ClassifyBox folds op by op, and an op that only exists inside a container is not
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// composable. Cost stated honestly: twelve predictable compares instead of one branch.
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/** Distance d'un point à un SEGMENT (pas à une droite). Écrite ici plutôt que prise dans
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* `FMath` : cinq lignes, aucune ambiguïté d'API, et elle sert une borne de correction — le
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* genre d'endroit où « je crois que cette fonction fait ça » n'est pas suffisant. */
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FORCEINLINE float VF_DistPointSegment(const FVector& P, const FVector& A, const FVector& B)
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{
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const FVector AB = B - A;
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const double LenSq = FVector::DotProduct(AB, AB);
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const double T = (LenSq > UE_KINDA_SMALL_NUMBER)
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? FMath::Clamp(FVector::DotProduct(P - A, AB) / LenSq, 0.0, 1.0)
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: 0.0;
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return (float)FVector::Dist(P, A + AB * T);
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}
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FORCEINLINE bool VF_NearCaveSurface(float Sdf, float SDFBlendRadius)
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{
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// Transcrit tel quel, ordre des comparaisons compris :
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@@ -2205,13 +2218,22 @@ namespace
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* opérateurs deviennent l'identité d'un coup** et la tuile est prouvable — c'est pour ça que
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* le câblage a été posé à UN endroit et pas treize.
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*
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* LE CRITÈRE, ET POURQUOI IL NE PEUT ÊTRE FAUX QUE DANS UN SENS.
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* `Eval` part de `MinSDF = FLT_MAX` et ne l'abaisse que via une primitive qui SURVIT à son
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* cull par voxel (sphère 3D pour les salles et les tunnels, bornes Z + cercle XY pour les
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* pits et les cheminées). Donc : si AUCUNE primitive du cache ne peut survivre à son cull en
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* un point quelconque de la boîte, `Sdf` reste `FLT_MAX` sur TOUTE la boîte, la source est
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* l'identité, et tout ce qui en dépend l'est aussi. On teste exactement ça — la même
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* inégalité que le cull par voxel, élevée du point à la boîte. Une seule raison d'échouer.
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* LE CRITÈRE — **UNE PRIMITIVE NE COMPTE PAS SI ELLE RATE SON CULL *OU* SI SON SDF RESTE
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* AU-DESSUS DU SEUIL `T`.** Une disjonction, pas une seule règle, et chaque branche gagne sur
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* une classe différente. Le détail de `T` et sa condition de validité sont dans la note
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* « LE SEUIL T » à l'intérieur de la fonction — la lire avant toute modification.
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*
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* • branche CULL — `Eval` part de `MinSDF = FLT_MAX` et ne l'abaisse que via une primitive
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* qui SURVIT à son cull par voxel. Aucune survivante ⇒ `Sdf` reste `FLT_MAX`. C'est la
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* même inégalité que le cull, élevée du point à la boîte. **Meilleure pour les salles** :
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* leur cull (`Rmax + 3K`) est plus serré que le seuil (`Rmax + T + K`).
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* • branche SEUIL — une primitive peut survivre à son cull et rester malgré tout trop loin
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* pour qu'un consommateur s'allume. **Meilleure pour les tunnels**, dont le cull est la
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* sphère englobante d'une capsule : rayon ~107 pour un tube de rayon 7 long de 200.
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*
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* Mélanger les deux est sûr : les primitives de la branche cull ne contribuent RIEN, les
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* autres sont toutes ≥ `T + K`, donc le pli vaut ≥ `T` (voir la saturation de `SmoothMin`),
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* et les trois consommateurs sont éteints. Une seule raison d'échouer, dans les deux cas.
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*
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* LES TROIS CHOSES QUI RENDENT LE TEST CONSERVATIF DU BON CÔTÉ :
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* 1. le warp déplace la coordonnée de REQUÊTE, donc la boîte est dilatée de sa borne
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@@ -2360,6 +2382,48 @@ namespace
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//
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// No early-out on purpose: stopping at the first hit gives the right verdict and no
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// information. When a zero has several possible causes, each gets its own number.
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//-----------------------------------------------------------------
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// ⚠️⚠️ LE SEUIL `T` — CE QUE `Identity` VEUT DIRE ICI, ET SA CONDITION DE VALIDITÉ
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//-----------------------------------------------------------------
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// Jusqu'ici `Identity` signifiait « `Sdf` reste `FLT_MAX` sur toute la boîte ». C'est
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// vrai, mais c'est plus fort que nécessaire, et cette force coûtait la quasi-totalité du
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// gain : aucun consommateur ne regarde `Sdf` au-delà d'un seuil.
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//
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// Les TROIS consommateurs du canal SDF de cette pile, RELUS un par un (pas supposés) :
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// • `FSdfConvertOp::Eval` → `if (InOut.Sdf >= Blend) return;` et
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// `BuildTunnelNetworkStack` l'instancie par `MakeSdfCarve(P.SDFBlendRadius, …)`
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// ⇒ seuil = `K`.
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// • les DOUZE modificateurs → `VF_NearCaveSurface` ⇒ seuil = `3·K`.
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// • `FWormFieldSource::Eval` → `if (CaveSDF >= P.WormNetworkRange) NetworkMask = 0;`
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// puis `if (NetworkMask <= 0) return;` ⇒ seuil = `WormNetworkRange`.
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// (`FCaveTerraceMod` re-sonde le SDF en Z±1, donc HORS de la boîte — mais son gate
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// `VF_NearCaveSurface` est testé AVANT la sonde, vérifié ligne par ligne. Un gate faux
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// partout ⇒ aucune sonde n'est jamais émise.)
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//
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// Donc `Sdf ≥ T` avec `T = max(K, 3K, WormNetworkRange)` suffit à éteindre les trois.
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//
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// ⚠️ **TOUT NOUVEAU CONSOMMATEUR DU CANAL `Sdf` DOIT AVOIR UN SEUIL ≤ T, OU ÊTRE AJOUTÉ
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// À CE `Max`.** C'est la seule dette de couplage de cette fonction, et elle est réelle :
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// un opérateur qui regarderait `Sdf < 100` verrait des verdicts `Identity` faux, donc
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// des tuiles sans géométrie ET SANS COLLISION. Écrit ici parce que c'est ici qu'on
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// atterrit en l'ajoutant.
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//
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// ⚠️ ET LA RAISON POUR LAQUELLE `− K` SUFFIT MALGRÉ N PRIMITIVES. `SmoothMin(A,B,K)`
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// vaut `min(A,B) − H³K/6` avec `H = max(K − |A−B|, 0)/K`. Deux conséquences lues sur la
|
||||
// formule : la pénalité est EXACTEMENT nulle dès que `|A−B| ≥ K`, et le minimum courant
|
||||
// ne peut donc jamais descendre plus de `K` sous le plus petit des termes — arrivé là,
|
||||
// `H = 0` et les plis suivants le laissent intact. D'où `Sdf ≥ min_i(SDF_i) − K` pour un
|
||||
// nombre QUELCONQUE de primitives, et non `− N·K/6`. C'est ce qui rend ce critère
|
||||
// utilisable au lieu d'être noyé sous le nombre de tunnels.
|
||||
//
|
||||
// Identity now means "Sdf >= T over the box", not "Sdf stays FLT_MAX" — no consumer
|
||||
// looks past its own threshold, and the three that exist were read one by one. ANY NEW
|
||||
// CONSUMER OF THE Sdf CHANNEL MUST HAVE A THRESHOLD <= T OR BE ADDED TO THIS MAX.
|
||||
// The -K slack covers any number of primitives because SmoothMin's penalty is exactly
|
||||
// zero once |A-B| >= K, so the running minimum saturates at K below the true minimum.
|
||||
const float K = FMath::Max(P.SDFBlendRadius, 0.0f);
|
||||
const float T = FMath::Max(3.0f * K, P.WormNetworkRange);
|
||||
|
||||
B.NumRooms = B.Cache.Rooms.Num();
|
||||
B.NumTunnels = B.Cache.Tunnels.Num();
|
||||
B.NumPits = B.Cache.Pits.Num();
|
||||
@@ -2370,9 +2434,60 @@ namespace
|
||||
{
|
||||
if (SphereHitsBox(R.Center, R.CullRadiusSq, QMin, QMax)) { ++B.HitRooms; }
|
||||
}
|
||||
for (const FCachedTunnel& T : B.Cache.Tunnels)
|
||||
//-----------------------------------------------------------------
|
||||
// LES TUNNELS ONT DROIT À UN SECOND TEST, ET C'EST LÀ QUE SE TROUVE LE GAIN
|
||||
//-----------------------------------------------------------------
|
||||
// ⚠️ CECI CHANGE LE SENS D'`Identity` POUR CET OPÉRATEUR — lire la note « LE SEUIL T »
|
||||
// ci-dessus avant de toucher quoi que ce soit ici.
|
||||
//
|
||||
// Le cull par voxel d'un tunnel est sa SPHÈRE ENGLOBANTE. Pour une capsule longue et
|
||||
// fine c'est une sur-estimation énorme : avec `MaxTunnelLength = 200` et
|
||||
// `TunnelMaxRadius = 7`, la sphère a un rayon jusqu'à ~107 pour un tube de rayon 7. La
|
||||
// mesure le disait sans ambiguïté — 32 tuiles bloquées sur 34 par des tunnels, contre
|
||||
// 21 par des salles.
|
||||
//
|
||||
// Donc : soit le tunnel rate son cull (il ne s'exécute pas), soit son PROPRE SDF reste
|
||||
// ≥ `T + K` sur toute la boîte (il s'exécute mais ne peut pas descendre le champ assez
|
||||
// bas pour qu'un consommateur s'allume). L'un ou l'autre suffit.
|
||||
//
|
||||
// La borne est exacte, pas prudente : `TaperedCapsule` rend
|
||||
// `Dist(P, PlusProcheSurSegment) − Lerp(Ra, Rb, t)`, donc
|
||||
// `SDF ≥ dist(P, segment) − max(Ra, Rb)` — RELU dans `VoxelCaveMorphology.h`, pas supposé.
|
||||
// Et `dist(boîte, segment) ≥ dist(centre, segment) − demi-diagonale` par inégalité
|
||||
// triangulaire : conservatif du bon côté, et trivialement vrai.
|
||||
//
|
||||
// A tunnel's per-voxel cull is its BOUNDING SPHERE — for a 200-long tube of radius 7
|
||||
// that sphere has radius ~107. So a tunnel does not matter if it fails that cull OR if
|
||||
// its own SDF stays >= T + K over the box. The bound is exact: TaperedCapsule is
|
||||
// genuinely dist-to-segment minus an interpolated radius, and box-to-segment distance is
|
||||
// bounded below by centre-to-segment minus the half-diagonal.
|
||||
const float TunnelClear = T + K;
|
||||
const FVector QCenter = (QMin + QMax) * 0.5;
|
||||
const float BoxHalfDiag = 0.5f * (float)(QMax - QMin).Size();
|
||||
|
||||
for (const FCachedTunnel& Tn : B.Cache.Tunnels)
|
||||
{
|
||||
if (SphereHitsBox(T.BoundCenter, T.BoundRadiusSq, QMin, QMax)) { ++B.HitTunnels; }
|
||||
if (!SphereHitsBox(Tn.BoundCenter, Tn.BoundRadiusSq, QMin, QMax)) { continue; }
|
||||
|
||||
float MaxR = FMath::Max(Tn.RadiusA, Tn.RadiusB);
|
||||
float DistToAxis;
|
||||
if (Tn.bHasMidpoint)
|
||||
{
|
||||
// Deux segments : le SDF du tunnel est le `Min` des deux, donc sa borne
|
||||
// inférieure est le `Min` des deux bornes.
|
||||
MaxR = FMath::Max(MaxR, Tn.RadiusMid);
|
||||
DistToAxis = FMath::Min(
|
||||
VF_DistPointSegment(QCenter, Tn.EndpointA, Tn.Midpoint),
|
||||
VF_DistPointSegment(QCenter, Tn.Midpoint, Tn.EndpointB));
|
||||
}
|
||||
else
|
||||
{
|
||||
DistToAxis = VF_DistPointSegment(QCenter, Tn.EndpointA, Tn.EndpointB);
|
||||
}
|
||||
|
||||
if (DistToAxis - BoxHalfDiag - MaxR >= TunnelClear) { continue; }
|
||||
|
||||
++B.HitTunnels;
|
||||
}
|
||||
// Miroir exact des deux `continue` de `Eval` : actif si `Z < TopZ + BlendK` ET
|
||||
// `Z >= TopZ - Depth - BlendK`.
|
||||
|
||||
Reference in New Issue
Block a user