A tile whose terrain lookup cast some lines kept castRequested set, so a
later refresh skipped it and the lines that failed stayed draped over
trees and roofs until the tile was rebuilt. A refresh now retries any tile
with lines still draped, and redraws it only when more of its lines can be
cast, so a tile that cannot be cast fully costs a cache check, not a
rebuild, per refresh. castRequested still stops the redraw from casting
again at once.
Co-Authored-By: Claude Opus 5.5 <[email protected]>