Fr0zkaandClaude Opus 5
e08b49a183
TunnelNetwork density evaluation was 45x more expensive than Maze for identical work: 2,097,152 voxels, 64 tiles, same mesher, same machine. Profiling killed every hypothesis I brought to it -- box classification skipping 0/64 tiles was true but irrelevant (export bypasses classification), near-surface early-outs fired at 49.7%, the room cache built 340 entries for 2.74M samples, and the per-room overrides resolved once per sample rather than once per modifier. The cause was the wrapper, not the stack. A mesher tile samples an EXPANDED grid (-1..Cells+1), so one worker crosses several exact chunk coordinates while meshing a single tile. The generator's cache held only the last coordinate, so every boundary crossing rebuilt the resolved parameters, the whole 22-operator stack and the tunnel-core cache. On one representative tile: 3,675 refetches, 38.0s. The entire operator stack was 18.5s of a 4,272s total -- 0.43%. Replaced with a 128-slot direct-mapped thread_local cache keyed on owner, chunk, layout version, params fingerprint and generator type. Collisions force a safe rebuild, never a stale read. No shared mutable state, no order-dependent reduction. TunnelNetwork 344.5s / 164.267 us/vox -> 18.4s / 8.763 us/vox (18.7x) Maze 7.4s / 3.535 us/vox -> 1.08s / 0.513 us/vox ( 6.9x) same tile 38.0s -> 0.51s ; refetches 3675 -> 27 Output is BYTE-IDENTICAL, before vs after and across repeats, both archetypes: TunnelNetwork 50d6b4d0..f23126, Maze 364f7489..2fbe99. The permission to change the field was not needed. Also in this commit, from the two preceding tasks: - Explorer renders from the MESH instead of raymarching. It meshes the region once through the canonical UVoxelMarchingCubesMesher, then CPU-rasterises via a BVH. A viewpoint went from ~16 minutes to 0.155s; 8 views now cost 1.25s of drawing. No render pixel samples the density field. - One sampled grid and player-fit mask per run, shared by render/walk/export, instead of the same 368s walk computed twice. - A wall-clock budget (25 min default, hard 30 max) that stops cleanly and records truncated/truncated_during/completed_modes rather than overshooting. - ParallelFor across the measurement sampling; the suite was ~10% of a 16-thread machine. - -surfaceroughness= on the commandlet, and a surface-relief metric in export mode (edge lengths, dihedral distribution, face-vs-smooth normal divergence) so "does this look like rock" is a number, not a screenshot argument. - Smooth vertex normals in the rasteriser: FVoxelMeshData::Normals is the density-gradient normal the engine shades with, and the raster path was recomputing a face normal over it. - ScaleDiagnosis: baked candidate indices are now derived from the current corpus, so a legitimate field change stops breaking the test. NOT verified, and not claimed: - TunnelNetworkSpineEquivalence exceeded the 30-minute cap and was stopped. Inconclusive, not passing. The identical hashes are strong evidence the op-stack/legacy equivalence holds, but the test has not confirmed it. - CrossPlatformDigest passes but reports 2 samples within 1e-6 of the isosurface; FMath::Sin/Cos leaves Windows/Linux equivalence unproven. Pre-existing, not caused by this change. - The cache's memory footprint (128 entries x ~16 workers) is unmeasured. What the roughness sweep settled, for the record: SurfaceRoughness 0 -> 8 moves cost by 0.3% (163.2 / 163.2 / 163.7 us), so roughness was never the cost. It does reach the surface (dihedral p50 1.1 -> 2.2 -> 5.9), which kills my claim that the density-channel operator contributed nothing. TunnelNetwork's hard seams are present at roughness 0 (4.4% of edges past 40 deg vs Maze's 1.0%), so they are structural -- in how primitives are unioned -- not a roughness deficiency. More roughness makes them worse, not better. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_012aheo2crrZmHuYtPpdY2Cb