Fullscreen and Scrolling world implementation

I took a quick glance at what you tried here. You are implementing two different behaviors for the world (scrolling and full-screen). However, the scrolling implementation was not intended for a full-screen world (and, of course, the full-screen implementation was not intended for a scrolling world). I am not saying that you cannot have both -- just that modification are required to allow them both to work together. It might be a bit difficult to come up with the proper modifications required; especially since you are not the author of either of those support classes.