Rule based images infrastructure.

Generate PPM format text file, then convert it to an actual jpg w/ ImageMagick.

% cat Foo.hs
#!/usr/bin/env runhaskell

import Data.List


pri :: Show a => [a] -> String
pri as = concat $ intersperse " " $ map show as

prip :: (Int,Int,Int) -> String
prip (r,g,b) = pri [r,g,b]

size :: Int
size = 50

wrap :: (Int,Int,Int) -> (Int,Int,Int)
wrap (r, g, b) = (r `mod` 256, g `mod` 256, b `mod` 256)

black :: (Int,Int,Int)
black = (0,0,0)

comb :: (Int,Int,Int) -> (Int,Int,Int) -> (Int,Int,Int)
comb (r1,g1,b1) (r2,g2,b2) = wrap (r1+r2,g1+g2,b1+b2)

comb2 :: (Int,Int,Int) -> (Int,Int,Int) -> (Int,Int,Int)
comb2 (r1,g1,b1) (r2,g2,b2) = wrap (r1 `mod` 64 +b2 `mod` 196,g1 `mod` 32+r2 `mod` 128,(1+b1 `mod` 16)*(1+g2 `mod` 16))

i :: Int -> [(Int,Int,Int)]
i wi = map wrap $ map (\i -> (11*i,truncate(sqrt(fromIntegral(7*i))),truncate((sin(fromIntegral(i))+fromIntegral(1))*fromIntegral(101)))) [1..wi]


wi :: [(Int,Int,Int)] -> [[(Int,Int,Int)]]
wi [] = []
wi ps =
  transpose [ take (length ps) (drop (length ps - 1) (cycle ps))
            , ps
            , take (length ps) (drop 1 (cycle ps))
            ]

step :: [(Int,Int,Int)] -> [(Int,Int,Int)]
step ps =
  map (\ps -> foldl comb black (drop 1 ps)) $ wi ps

alg :: [[(Int,Int,Int)]] -> [[(Int,Int,Int)]]
alg [] = [i size]
alg (h:t) = (step h):h:t

main = do
  putStrLn "P3"
  putStrLn $ pri [size, size]
  putStrLn $ "255"
  mapM_ putStrLn $ map prip $ concat $ iterate alg [] !! size
% ./Foo.hs > 0119.ppm && convert 0119.ppm -filter box -resize 1600% 0119.jpg
%