Fr0zka
7dbdf51b44
CORRECTNESS on a box verdict, not perf. This file derives |Perlin3D| <= 1.5
rigorously, exposes it as PerlinAbsBound, uses it for the tunnel warp, and says
outright that the header's "~[-1,1]" is an observation and that a box verdict
resting on one is a hole. Three ExtraReach formulas in the same file assumed
sup|FBM| <= 1.0 -- and VoxelNoise::FBM normalises (Total / MaxValue), so
sup|FBM| = sup|Perlin3D| exactly. The bound was wrong by 1.5x.
At shipped defaults, soundness needed B <= 1.27 (VerticalShafts, Rough 3.0) and
B <= 1.40 (Maze, Rough 2.0); both are violated at B = 1.5. Break-even roughness
is 1.6. FloatingIslands survives only because its SDFBlendRadius is 5 -- sound
by parameter luck, not construction.
Nothing in the running game was affected (no strate has bUseOperatorStack
ticked) and the empirical Perlin sup ~1.0-1.1 is why nothing surfaced. But the
tile scans SAMPLE, and for shafts they sampled a source that proved zero tiles
until e002bd4 -- which is what makes this reachable rather than latent.
Fix: PerlinAbsBound hoisted to file scope as VF_PerlinAbsBound (one definition,
not a class-static plus three implicit 1.0s) and multiplied into all three
reaches; the three comments now state the real justification instead of the
refuted one.
Cannot change density: ExtraReach is read only inside EffectOverBox, verified
mechanically -- no Eval/GetCells line appears in the diff. Direction is strictly
conservative, so it can only cost CPU. Expect FEWER proved tiles for Maze and
VerticalShafts; that is the correct outcome, not a regression.
Not built -- Jahni builds.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>