Add support for directional sound

src/Sound.hs

@@ -63,7 +63,9 @@ updateSounds sd ss = do
 
 updateSound :: IM.IntMap Mix.Chunk -> Sound -> MaybeT IO Sound
 updateSound sd s =
-    initialisePlaying sd s >>= liftIO . decrementTimer >>= cleanupHalted
+    initialisePlaying sd s 
+    >>= liftIO . (decrementTimer >=> applyPosition) 
+    >>= cleanupHalted
 
 initialisePlaying :: IM.IntMap Mix.Chunk -> Sound -> MaybeT IO Sound
 initialisePlaying sd s = case _soundStatus s of
@@ -98,6 +100,12 @@ decrementTimer s = case _soundTime s of
                                          & soundStatus .~ FadingOut)
     Nothing -> return s
 
+applyPosition :: Sound -> IO Sound
+applyPosition s = case _soundPos s of
+    Nothing     -> return s
+    Just (a,d)  -> Mix.effectPosition (fromJust $ _soundChannel s) a d
+                    >> return (s & soundPos .~ Nothing)
+
 fadeOutMaybe :: Maybe Mix.Channel -> Int -> IO ()
 fadeOutMaybe (Just x) fadeT = Mix.fadeOut (fromIntegral fadeT + 1) x
 fadeOutMaybe _ _ = return ()