Minor cleanups

src/Sound.hs

@@ -56,9 +56,10 @@ playSoundAndUpdate sData oldSounds newSounds
 mergeSound :: Sound -> Sound -> Sound
 mergeSound oldS newS
     | _soundChunkID newS == _soundChunkID oldS && _soundStatus newS == ToContinueStart
-                = newS & soundChannel .~ _soundChannel oldS
-                       & soundStatus  .~ _soundStatus oldS
-    | otherwise = newS & soundChannel .~ _soundChannel oldS
+                = newOldChannel & soundStatus  .~ _soundStatus oldS
+    | otherwise = newOldChannel
+  where
+    newOldChannel = newS & soundChannel .~ _soundChannel oldS
 
 updateSounds :: IM.IntMap Mix.Chunk -> M.Map a Sound -> IO (M.Map a Sound)
 updateSounds sd ss = do
@@ -95,7 +96,7 @@ tryGetChannel s = case _soundChannel s of
 decrementTimer :: Sound -> IO Sound
 decrementTimer s = case _soundTime s of
     Just t 
-        | t > 0     -> return $ s & soundTime ?~ t - 1
+        | t > 0     -> return $ s & soundTime . _Just -~ 1
         | otherwise -> do 
             forM_ (_soundChannel s) Mix.halt
             return $ s & soundTime .~ Nothing
@@ -120,7 +121,6 @@ cleanupHalted s = do
 For each index, the corresponding sound starts playing if there is a free channel.
 Use this if you don't care about timing, overlapping, fading, or sound positions.  -}
 playSoundQueue :: IM.IntMap Mix.Chunk -> [Int] -> IO ()
---playSoundQueue chunkMap ns = forM_ ns $ \n -> runMaybeT $ playIfFree (chunkMap IM.! n) Mix.Once
 playSoundQueue chunkMap = mapM_ $ \n -> runMaybeT $ playIfFree (chunkMap IM.! n) Mix.Once
 
 {- | Given a chunk, attempt to play this on a free channel a given number of
@@ -134,8 +134,9 @@ playIfFree c times = do
 {- | Play sounds from a list of index/position pairs.
 As for 'playSoundQueue', but with positional information in the form of an Int16.  -}
 playPositionalSoundQueue :: IM.IntMap Mix.Chunk -> [(Int,Int16)] -> IO ()
-playPositionalSoundQueue chunkMap = VS.mapM_ ( \(n,a) -> 
-    runMaybeT $ playIfFree (chunkMap IM.! n) Mix.Once >>= setChannelPos a )
+playPositionalSoundQueue chunkMap 
+    = VS.mapM_ ( \(n,a) -> 
+                runMaybeT $ playIfFree (chunkMap IM.! n) Mix.Once >>= setChannelPos a )
     . VS.fromList
 
 setChannelPos :: Int16 -> Mix.Channel -> MaybeT IO Mix.Channel