type t
val blit : (t, t) Base.Blit_intf.blit
val blito : (t, t) Base.Blit_intf.blito
val unsafe_blit : (t, t) Base.Blit_intf.blit
val sub : (t, t) Base.Blit_intf.sub
val subo : (t, t) Base.Blit_intf.subo