Layers makes more sense than regions to me. X and Y are Lat and Long on a map which makes Z altitude.
I'm looking at cChunkMap.cpp right now. I'm determined to figure this out.
What's the difference between ChunkMap and ChunkData and ChunkLayer?
Is a ChunkLayer the full contents of the Pak file?
I can see in cChunkLoader::LoadFormat1 in cChunkLoader.cpp that the pak location is obtained by simply dividing the chunk's coordinates by 16 (and using int and floorf).
I think I have a basic idea of how that works, I just don't know how MCServer works with the data from the file yet.
I'm looking at cChunkMap.cpp right now. I'm determined to figure this out.

What's the difference between ChunkMap and ChunkData and ChunkLayer?
Is a ChunkLayer the full contents of the Pak file?
I can see in cChunkLoader::LoadFormat1 in cChunkLoader.cpp that the pak location is obtained by simply dividing the chunk's coordinates by 16 (and using int and floorf).
I think I have a basic idea of how that works, I just don't know how MCServer works with the data from the file yet.