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module Main (main) where
import Data.Bifunctor (Bifunctor, bimap)
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy as BL
import Data.List (foldl', transpose)
import qualified Data.Text as T
import Debug.Trace
import PFM
data Direction = Horizontal | Vertical
deriving (Show, Eq)
data Cut = Cut Direction Int
deriving (Show, Eq)
bbimap :: Bifunctor p => (a -> d) -> p a a -> p d d
bbimap a = bimap a a
clamp :: Float -> PFMColour -> PPMColour
clamp stop (PFMColour ri gi bi) = PPMColour (f ri) (f gi) (f bi)
where
v s = (s * (2 ** stop)) * 255
f s = if v s > 255 then 255 else fromInteger (floor (v s))
clamp _ _ = undefined
clampImage :: Float -> PFMImage -> PPMImage
clampImage stop (PFMImage w h c) = PPMImage w h $ fmap (clamp stop) <$> c
fixIntensity :: Int -> Int -> PFMColour -> Double
fixIntensity sizeY y (PFMColour r g b) =
sin ((fromIntegral y / fromIntegral sizeY) * pi) * (f r + f g + f b) / 3
where f = realToFrac
fixIntensity _ _ _ = error "Mono not supported"
findSplit :: [Double] -> Int
findSplit d = findSplit'_ d [] 0
where
findSplit'_ (x : ds) e i | sum ds < sum e = i
| otherwise = findSplit'_ ds (x : e) $ i + 1
findSplit'_ _ _ i = i
findEnergy :: [Double] -> (Double, Double)
findEnergy d = bbimap sum $ splitAt (findSplit d) d
cfmap :: Functor f => (t -> a -> b) -> t -> f a -> f b
cfmap f a b = f a <$> b
findSplitLine' :: [[Double]] -> Int
findSplitLine' = findSplit . fmap sum
findSplitLine :: [[Double]] -> Cut
findSplitLine d | length d > length (head d) = Cut Horizontal $ findSplitLine' d
| otherwise = Cut Vertical . findSplitLine' $ transpose d
energies :: [[Double]] -> ((Double, Double), [Double])
energies d | length d > length (head d) = (bs . splitAt (findSplitLine' d) $ fmap sum d, fmap sum d)
| otherwise = (bs . splitAt (findSplitLine' d') $ fmap sum d', fmap sum d')
where
bs = bbimap sum
d' = transpose d
drawCut' :: PFMColour -> Cut -> (Int, Int) -> PFMColour -> PFMColour
drawCut' c (Cut Vertical n) (_, x) c' | x == n = c
| otherwise = c'
drawCut' c (Cut Horizontal n) (y, _) c' | y == n = c
| otherwise = c'
drawCut :: PFMColour -> Cut -> [[PFMColour]] -> [[PFMColour]]
drawCut c cut colour = (zipWith . zipWith)
(drawCut' c cut)
[ [ (y, x) | x <- [0 .. length $ head colour] ] | y <- [0 .. length colour] ]
colour
applyGamma :: Float -> PFMImage -> PFMImage
applyGamma g (PFMImage w h c) = PFMImage w h $ fmap gc <$> c
where gc (PFMColour r gr b) = PFMColour (gamma g r) (gamma g gr) (gamma g b)
split :: Cut -> [[a]] -> ([[a]], [[a]])
split (Cut Horizontal n) l = splitAt n l
split (Cut Vertical n) l = bbimap transpose . splitAt n $ transpose l
combine :: Cut -> ([[a]], [[a]]) -> [[a]]
combine (Cut Horizontal _) (a, b) = a ++ b
combine (Cut Vertical _) (a, b) = zipWith (++) a b
fIntens :: [[PFMColour]] -> [[Double]]
fIntens d = zipWith (cfmap . fixIntensity $ length d - 1) [0 ..] d
findCentroid :: [[Double]] -> (Int, Int)
findCentroid d = (y, x)
where
y = findSplitLine' d
x = findSplitLine' $ transpose d
drawCentroid' :: PFMColour -> Int -> (Int, Int) -> (Int, Int) -> PFMColour -> PFMColour
drawCentroid' ci s (xi, yi) (x, y) c | (x - xi)^2 + (y - yi)^2 < round ((fromIntegral s/2)**2) = ci
| otherwise = c
drawCentroid :: PFMColour -> [[Double]] -> [[PFMColour]] -> [[PFMColour]]
drawCentroid ic d c = (zipWith . zipWith)
(drawCentroid' ic 9 pt)
[ [ (y, x) | x <- [0 .. length $ head c] ] | y <- [0 .. length c] ]
c
where pt = findCentroid d
drawCentroidBlack' :: PFMColour -> Int -> (Int, Int) -> (Int, Int) -> PFMColour -> PFMColour
drawCentroidBlack' ci s (xi, yi) (x, y) _ | (x - xi)^2 + (y - yi)^2 < round ((fromIntegral s/2)**2) = ci
| otherwise = PFMColour 0 0 0
drawCentroidBlack :: PFMColour -> [[Double]] -> [[PFMColour]] -> [[PFMColour]]
drawCentroidBlack ic d c = (zipWith . zipWith)
(drawCentroidBlack' (totalRadiance c) 9 pt)
[ [ (y, x) | x <- [0 .. length $ head c] ] | y <- [0 .. length c] ]
c
where pt = findCentroid d
add :: PFMColour -> PFMColour -> PFMColour
add (PFMColour r1 g1 b1) (PFMColour r2 g2 b2) = PFMColour (r1 + r2) (g1 + g2) (b1 + b2)
add _ _ = error "Mono not supported"
totalRadiance :: [[PFMColour]] -> PFMColour
totalRadiance c = f $ f <$> c where f = foldl' add (PFMColour 0 0 0)
recSplitGeneral
:: (Eq a1, Num a1)
=> (PFMColour -> [[Double]] -> [[a2]] -> [[a3]])
-> (PFMColour -> Cut -> [[a3]] -> [[a3]])
-> a1
-> [[Double]]
-> [[a2]]
-> [[a3]]
recSplitGeneral dFun _ 0 d c = dFun (PFMColour 0 0 1) d c
recSplitGeneral dFun dCut n d c = dCut (PFMColour 1 1 1) cut a
where
cut = findSplitLine d
a = combine cut . apply nrec $ split cut c
(d1, d2) = split cut d
nrec = bbimap (recSplitGeneral dFun dCut (n - 1)) (d1, d2)
apply (f, g) (a', c') = (f a', g c')
recSplitRadiance, recSplit :: Int -> [[Double]] -> [[PFMColour]] -> [[PFMColour]]
recSplit = recSplitGeneral drawCentroid drawCut
recSplitRadiance = recSplitGeneral drawCentroidBlack (\_ _ -> id)
generateCuts
:: Show a
=> Float
-> (a -> [[Double]] -> [[PFMColour]] -> [[PFMColour]])
-> PFMImage
-> String
-> a
-> IO ()
generateCuts stop splitFun image prefix i = do
putStrLn $ "data/" ++ prefix ++ show i ++ ".ppm"
BL.writeFile ("data/" ++ prefix ++ show i ++ ".ppm")
. encodePPM
. clampImage stop
. applyGamma 2.2
$ img
putStrLn $ "data/" ++ prefix ++ show i ++ ".pfm"
BL.writeFile ("data/" ++ prefix ++ show i ++ ".pfm") . encode . revColour $ img
where
newColour = splitFun i (fIntens $ pfmColour image) $ pfmColour image
img = PFMImage (pfmWidth image) (pfmHeight image) newColour
main :: IO ()
main = do
im <- B.readFile "data/grace_latlong.pfm"
let grace = revColour $ parse im
mapM_ (generateCuts 0 recSplit grace "median_cut") [1 .. 10]
mapM_ (generateCuts (-6) recSplitRadiance grace "median_cut_radiance") [6]
|
