How do Maps behave in the Game?

[gaveitatry]

In the Intersect Client (the game), how does the map transitioning work?  What happens when I walk close to a map border?  What happens when I cross the map border into a new map?

[gaveitatry]

In Mystica, a game that I play that uses a different engine, the maps are like rooms where you walk to the end of the room, the screen changes, and suddenly you appear in a new room but can no longer see the old one.  I just found out that Intersect is way better.  In Intersect, you can see both rooms at the same time, and your character is always in the center of the screen with the camera always following it.