Simple screenshot folding via repa library.

Main.hs

{-# LANGUAGE UnicodeSyntax #-}
module Main where

import Control.Applicative ((<$>))
import System.Directory (getDirectoryContents)
import System.FilePath ((</>))
import Data.Array.Repa.IO.DevIL
import qualified Data.Array.Repa as R

main ∷ IO ()
main = do
  image_files ← map ("img" </>) . filter (`notElem` [".",".."]) <$> getDirectoryContents "img"
  runIL $ do
    images ← mapM readImage image_files
    let xs = [R.transpose x | RGB x ← images]
    z ← R.computeP $ R.transpose $ foldr1 (R.++) xs
    writeImage "POLOTNISHE.png" $ RGB z