Add file, move buffer swapping into doDrawing

src/Loop.hs

@@ -200,7 +200,8 @@ setupConLoop' ::
     ---- | Concurrent effects. Evaluating 'Nothing' exits the loop
     (world -> ConcurrentEffect world) ->
     -- | update, called once per frame. Allows for side effects such as rendering.
-    (world -> IO world) ->
+    -- passes the window to allow buffer swapping
+    (Window -> world -> IO world) ->
     -- | SDL Event handling, once per frame. Note no side effects.
     (world -> Event ->  world) ->
     IO ()
@@ -232,7 +233,7 @@ doConLoop' ::
     (world -> ConcurrentEffect world) ->
     -- | simulation update. Allows for side effects such as rendering.
     -- passes the window to allow buffer swapping at different times
-    (world -> IO world) ->
+    (Window -> world -> IO world) ->
     -- | SDL Event handling. Note no side effects.
     (world -> Event -> world) ->
     -- | Current simulation state.
@@ -240,6 +241,7 @@ doConLoop' ::
     IO ()
 doConLoop' themvar spf window coneffs worldSideEffects eventFn !startWorld = go startWorld
   where
+    worldSideEffectsWindow = worldSideEffects window
     go sw = do
         startTicks <- ticks
         es <- pollEvents
@@ -258,8 +260,8 @@ doConLoop' themvar spf window coneffs worldSideEffects eventFn !startWorld = go
         case mstartWorld' of
             Nothing -> return ()
             Just startWorld' -> do
-                worldAfterSimStep <- worldSideEffects startWorld'
-                glSwapWindow window
+                worldAfterSimStep <- worldSideEffectsWindow startWorld'
+--                glSwapWindow window
                 let updatedWorld = foldl' eventFn worldAfterSimStep es
                 performGC
                 endTicks <- ticks -- it might be better to use System.Clock (monotonic)