How Map Location Works.

I've been trying to mod maps to be a single screen so no scrolling is needed, however the overlay icons still show "you are here", the home points etc where they would be if the image was the original size.



Does anyone have any idea how this overlay gets its data? is there a file with the locations of every map somewhere or is it sent from the server and so can't be changed? I know the icon image data is in the UI file but I don't think it holds locations of all maps.