Remove targeting bugs

src/Dodge/Update.hs

@@ -1,4 +1,4 @@
-{-# LANGUAGE BangPatterns #-}
+--{-# LANGUAGE BangPatterns #-}
 
 {- |
 Module      : Dodge.Update
@@ -653,7 +653,7 @@ updateSeenWalls :: World -> World
 updateSeenWalls w = foldl' markWallSeen w (map (_wlID . snd) $ allVisibleWalls w)
 
 markWallSeen :: World -> Int -> World
-markWallSeen w i = w & cWorld . seenWalls . at i .~ Just ()
+markWallSeen w i = w & cWorld . seenWalls . at i ?~ ()
 --markWallSeen !w !i = w & cWorld . lWorld . walls %~ IM.adjust markSeen i
 -- in the past there might have been a space leak, which the following was meant
 -- to fix