Priority offset added to a preload-ring (off-screen) load so it always sorts
AFTER every in-view load in the cache's priority dispatch — warming the ring must
never delay a visible tile. Larger than any real camera-to-tile distance (≫ a
planet diameter), so ring loads only start once the on-screen frontier is busy.
Priority offset added to a preload-ring (off-screen) load so it always sorts AFTER every in-view load in the cache's priority dispatch — warming the ring must never delay a visible tile. Larger than any real camera-to-tile distance (≫ a planet diameter), so ring loads only start once the on-screen frontier is busy.