Old Style Minimaps

[Hippogriff]

This is more of a theory based question then anything directly related to C++ but this is the best place I have to ask so I will try! (Maybe should be in lounge...)

While messing around on Ocarina of Time I stared at the minimap and wondered how they managed to do it without taking up too much time/memory (The minimap being done by hand seems crazy). I know most modern 3D games just position a 2nd camera above the player pointing straight down with a large FOV but I can't tell if that is what is being done here. http://puu.sh/7SkXM.jpg http://puu.sh/7SlLi.png

Another thing I don't see how they managed to do is compute the borders (black lines) so well. I can think of a few ways they could of done this by looking at the height/normal vectors of the planes but I can't see a fully reliable method.
There are certain parts of the world you can walk on with cheat codes that aren't shown on minimap so it isn't a pure geometry copy.

Maybe I just ask too many questions but I am always interesting to see how old games do things :D.

[Peter87]

I don't think it's likely that the minimap is automatically generated from the terrain. After making a whole room, marking out the minimap borders is probably not much work in comparison.

[Hippogriff]

So you think they actually did create all of the minimaps by hand?
Seems like a lot of work for every map in the game + every dungeon etc.