[2021] Map Generator Question

Something like this might be possible, but I don't think it will be a Vanilla feature. Probably something that KingGen would be capable of if it was developed to support it.
More likely it would just calculate based on visible data in the image rather than pulling from the Google API though.

Originally posted by DocRabbit: Take a look into NitroGen custom maps, it should be quite easy to do, you will just need a 256 grayscale heightmap of the location, scaled to 8k or whatever size you are hoping for.

No don't.

Nitrogen died before a19 went stable. It will not function with a20.
If you want a custom map now, you will use KingGen, but only after it updates for a20.