23 lines
543 B
Haskell
23 lines
543 B
Haskell
module Bound (
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boundPoints,
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) where
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import qualified Control.Foldl as L
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import Control.Lens
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import Geometry
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---- NSEW
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boundPoints :: [Point2] -> Maybe (Float, Float, Float, Float)
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{-# INLINE boundPoints #-}
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boundPoints =
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f
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. L.fold
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( (,,,)
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<$> L.premap (^?! _2) L.maximum
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<*> L.premap (^?! _2) L.minimum
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<*> L.premap (^?! _1) L.maximum
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<*> L.premap (^?! _1) L.minimum
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)
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where
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f (mn, ms, me, mw) = (,,,) <$> mn <*> ms <*> me <*> mw
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