import Graphics.Gloss

type Model = [Picture -> Picture]

fractal :: Int -> Model -> Picture -> Picture
fractal n model pict = pictures $ take n $ iterate (mconcat model) pict

tree1 _ = fractal 10 branches $ Line [(0,0),(0,100)]
  where branches = [ Translate 0 100 . Scale 0.75 0.75 . Rotate 30
                   , Translate 0 100 . Scale 0.5 0.5 . Rotate (-30) ]

main = animate (InWindow "Tree" (800, 800) (0, 0)) white $ tree1 . (* 60)