Concept Help: Screen Transition Scripting

I'm having trouble reconciling with the way in which people script around screen scrolling. I get that the general idea is to record the current screen against a stored screen variable to check for a change, but I'm having trouble setting this up effectively.

I'm trying to record the last combo Link was standing on before a screen change, and--if he was standing on a particular combo--shift his coordinates as the screen scrolls (or if that isn't possible, immediately after the screen scrolls.


So I'd like to ask what's the best way to check for a screen change, as well as record a combo before a screen transition [Waitdraw() doesn't work for this, it updates to the arrival combo too soon]. The screen change does not have to be sophisticated; it only needs to detect a scrolling event.


Anybody know how to do this?