InstagraML chess board

gistfile1.ML

fun chess idim = 
  let val dim = Real.fromInt idim
      fun rep3 v = (v,v,v)
      fun chess' (ii, ij) =
          let val (i,j) = (Real.fromInt ii,
                           Real.fromInt (idim-ij))
              val s = 3.0/(j+99.0)
          in (Real.round((i+dim)*s+j*s) mod 2 + 
              Real.round((dim*2.0-i)*s+j*s) mod 2)*127
          end
  in InstagraML.fromFunction (idim, idim, rep3 o chess')
  end

InstagraML.writeBMP ("chess.bmp", chess 1024);