[ut2003io] Map editing

[Ryan C. Gordon]

> Or UnrealEd I take it. So it's like a compiled format but without a compiler 
> (you could store the map in a different format but convert it to the actual 
> map format when you want to test it).
> 
> Or is that how you are doing it? I'm a little unclear on this.

UnrealEd links against the engine's libraries, so the same code manages 
maps in the game and the editor. The format is complicated, and it's 
subject to change rapidly (sometimes between patches), so it's a moving 
target.

--ryan.