The visibility texture has binary per-tile values (0/180/255) — bilinear
filtering alone only smooths ~1 tile, producing hard stair-stepped edges
at the LOS boundary instead of the 6-8 sim tile gradient D-059 specifies.
Add sample_visibility() with 7x7 Gaussian kernel (sigma 2.0) that
spreads the LOS boundary into a 3-4 tile radius gradient. Lower
PERIPHERAL_LOW from 0.55 to 0.08 so gradient tiles enter the peripheral
fog branch. Fix Layer 1/2 alpha discontinuity at CLEAR_THRESHOLD.
Guard against gradient bleed into unexplored tiles.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
jpmschweitzerandClaude Opus 4.6
df1d9c8990
