Rotation (user-directed): the procedural starfield rotates once per
Dereth day (~2 real hours - constellations visibly wheel through a
night) about a celestial pole ~41 deg above the northern horizon, plus
dayOfYear/360 of seasonal drift so the 360-day year changes the night
sky. One SkyParams float (272-byte block, layout test re-pinned)
carries dayFraction + dayOfYear/360 from the world clock; sky.frag
applies a Rodrigues rotation to the sample direction so stars and
mottle turn together. Impossible with retail's static stretched layer.
Fade rework (the 2026-08-23 two-screenshot gate finding): the
per-vertex vTint signal carried the sun-facing product and blanked
stars across the entire twilight half of the sky. The fade now reads
the UNIFORM ambient term - identical star visibility in every compass
direction, same dusk-to-dawn schedule - with one deliberate exception:
a thin suppression band hugging the low sky toward the sun's azimuth
while the sun term is strong, so stars still wash out inside the
actual twilight glow.
Guards updated (rotation anchor, uniform-fade anchor, 272-byte layout);
both sky SPIR-V hashes re-pinned.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>