Refactor event handling. Allow mouse movement in menus

src/Sound.hs

@@ -14,6 +14,9 @@ module Sound (
     , playPositionalSoundQueue
     -- * Complex Playback
     , playAndUpdate
+    -- * Volume Control
+    , setSoundVolume
+    , setMusicVolume
     ) where
 import Sound.Data
 
@@ -149,3 +152,18 @@ setChannelPos :: Int16 -> Mix.Channel -> MaybeT IO Mix.Channel
 setChannelPos a i = do
     liftIO $ Mix.effectPosition i a 0 
     return i
+
+
+-----------------------------------------------------------------
+{- | Set the volume for all sound channels.
+Behind the scenes, scales a float [0,1] to an Int [0..128].
+ -}
+setSoundVolume :: Float -> IO ()
+setSoundVolume x = Mix.setVolume (round (x * 128)) Mix.AllChannels
+
+{- | Set the music volume.
+Behind the scenes, scales a float [0,1] to an Int [0..128].
+ -}
+setMusicVolume :: Float -> IO ()
+setMusicVolume x = Mix.setMusicVolume (round (x * 128))
+