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module Graphics.HDemo.Utils( quads, fractionToWord16, word16ToFraction ) where
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import Data.Word( Word16 )
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fractionToWord16 :: Double -> Word16
fractionToWord16 = round . ((fromIntegral (maxBound::Word16))*)
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word16ToFraction :: Word16 -> Double
word16ToFraction p = (fromIntegral p) / (fromIntegral (maxBound::Word16))
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quads :: [a] -> [(a,a,a,a)]
quads [] = error "no elements"
quads (x:[]) = [(x,x,x,x)]
quads (x:y:[]) = [(x,y,y,y)]
quads (x:y:z:[]) = [(x,y,z,z)]
quads (x:y:z:w:xs) = (x,y,z,w) : quads (y:z:w:xs)
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