Code review identified a latent false-positive flake risk: physics
path clamps fx = localX/24 to (CellsPerSide - 0.001f) = 7.999, which
corresponds to localX <= 191.976. With samples up to 191.999f,
physics computes Z at the clamped position while the mesh sampler
uses the actual position — a difference of up to 23 mm at the upper
edge, which on a steep slope would falsely trip the 1 mm sentinel.
Tighten upper bound to 191.975f (strictly below the clamp boundary)
so both oracles compute Z at the same (cellX, tx). Also restored the
"worst-case from SplitFormulaDivergenceTest" inline comment for
landblock 0x4D96 per code review suggestion #3.
Test still passes: 10/10 landblocks, 1000 samples, max |delta|
= 0.0153 mm (previously 0.0305 mm — confirms the prior worst-case
was indeed at the boundary).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Z-conformance sentinel for issue #51's bug class. Sweeps 10
representative landblocks x 100 sample points (uniform random in
local 0..192 with fixed seed 42). For each point: compute meshTriZ
via barycentric interpolation in the matching triangle of the
LandblockMesh.Build output; compute physicsZ via
TerrainSurface.SampleZFromHeightmap; assert |delta| < 0.001m.
Catches any silent formula or vertex-layout drift between the
visual and physics paths. Skips gracefully if ACDREAM_DAT_DIR
isn't set (CI without dat data).
Local run with dat data: 10/10 landblocks loaded, 1000 samples,
max |delta| = 0.0305 mm (worst case: Direlands 0xC040).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
