I don't really know, because by the time I turn around to check I've already looked at it. :p

It's an interesting idea though, I saw a YouTube video a few months back where the camera for the unreal engine was moved away from where it normally sits to some ways away, and as the player character moved around you could see the slice of the world coming into existence. It totally works in the unreal engine because you can only look at what you are looking at.