Constant ROOM_SURF_OPTIONS_CYCLES 

pub const ROOM_SURF_OPTIONS_CYCLES: u16 = 250;

E2 (docs/engine-30fps-architecture-2026-07-26.md): cycles rebuilding the per-surface WorldSurfaceOptions variants. This sits between the timed lighting and submit sections, i.e. inside the ~48% of room_surface_draw that no existing counter attributed.