    {-# LANGUAGE ExplicitForAll #-}

    -- We export this stuff separately so we don't clutter up the
    -- API of the Graphics.Gloss module.

    -- | This game mode lets you manage your own input. Pressing ESC will still abort the program,
    --   but you don't get automatic pan and zoom controls like with `displayInWindow`.
    module Graphics.Gloss.Interface.Pure.Game
            ( module Graphics.Gloss.Data.Display
            , module Graphics.Gloss.Data.Picture
            , module Graphics.Gloss.Data.Color
            , play
            , Event(..), Key(..), SpecialKey(..), MouseButton(..), KeyState(..), Modifiers(..))
    where
    import Graphics.Gloss.Data.Display
    import Graphics.Gloss.Data.Picture
    import Graphics.Gloss.Data.Color
    import Graphics.Gloss.Internals.Interface.Game
    import Graphics.Gloss.Internals.Interface.Backend

    -- | Play a game in a window. Like `simulate`, but you manage your own input events.
    play    :: Display              -- ^ Display mode.
            -> Color                -- ^ Background color.
            -> Int                  -- ^ Number of simulation steps to take for each second of real time.
            -> world                -- ^ The initial world.
            -> (world -> Picture)   -- ^ A function to convert the world a picture.
            -> (Event -> world -> world)
                    -- ^ A function to handle input events.
            -> (Float -> world -> world)
                    -- ^ A function to step the world one iteration.
                    --   It is passed the period of time (in seconds) needing to be advanced.
            -> IO ()

    play    display backColor simResolution
            worldStart worldToPicture worldHandleEvent worldAdvance

     = playWithBackendIO defaultBackendState
            display backColor simResolution
            worldStart
            (return . worldToPicture)
            (\event world -> return $ worldHandleEvent event world)
            (\time  world -> return $ worldAdvance     time  world)
            True