SBMAP Mapfile Format

File is a linear integer array.

Header: 8ints
-------------------------------------
offset | size | description
-------------------------------------
0      | 1    | magic constant "MAP:"
1      | 1    | SBMAP version
2      | 1    | Always 0. Unknown.
3      | 1    | layer count (4)
4      | 1    | ?? DW
5      | 1    | ?? DH
6      | 1    | ?? MX
7      | 1    | ?? MY