# cloister_stone Wet monastery stone for the Verdigris Cloister — coursed slabs in a running bond, mineral grain, standing water in the hollows and moss coming out of every joint. It is triplanar off world space, so the floor, the piers, the plinths and the walls all wear it without an authored UV between them, and two pieces of stone that meet share a course line. `slab_size` sets the coursing, `moss_amount` and `moss_up` how far the moss has got and whether it only takes the up-facing stone, `wetness` how much of the floor is under water. Exposes `surface()`, so the engine lights it and the PBR debug passes read the real channels.