Groundtype tends to be a smattering of random values for the whole grid. The important part is that they have somewhat reasonably sized contiguous clusters (where the groundtype is consistent for some radius of tiles).
Think: generate random circles of random values, and stop when all tiles have a value that is non 0.
Anything that is remotely more efficient will be accepted.
Note, admins can still paint groundtypes manually, this just ensures no location is without a valid groundtype. (there are issues with 71/72)
Groundtype tends to be a smattering of random values for the whole grid. The important part is that they have somewhat reasonably sized contiguous clusters (where the groundtype is consistent for some radius of tiles). Think: generate random circles of random values, and stop when all tiles have a value that is non 0. Anything that is remotely more efficient will be accepted.
Note, admins can still paint groundtypes manually, this just ensures no location is without a valid groundtype. (there are issues with 71/72)