Add file

src/Dodge/Data/ScreenPos.hs

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+{-# LANGUAGE StrictData #-}
+{-# LANGUAGE TemplateHaskell #-}
+module Dodge.Data.ScreenPos
+    where
+
+import Geometry.Data
+import Control.Lens
+
+data ScreenPos = ScreenPos
+    { _spScreenOff :: Point2
+    , _spPixelOff :: Point2
+    }
+makeLenses ''ScreenPos

src/Dodge/ScreenPos.hs

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+module Dodge.ScreenPos where
+
+import Dodge.Base.Window
+import Dodge.Data.Config
+import Dodge.Data.ScreenPos
+import Geometry.Data
+import Picture.Base
+import Control.Lens
+
+fromTopLeft :: Point2 -> ScreenPos
+fromTopLeft (V2 x y) = ScreenPos (V2 (-0.5) 0.5) (V2 x (- y))
+
+translateScreenPos :: Configuration -> ScreenPos -> Picture -> Picture
+translateScreenPos cfig sp = translate x y
+  where
+    V2 x y = sp ^. spScreenOff * V2 hw hh + sp ^. spPixelOff
+    hw = halfWidth cfig
+    hh = halfHeight cfig