this is not a supported feature, so I'd rather not document.
this "cucumber" test spells out how it currently works: https://github.com/wagn/wagn/blob/master/features/google_maps.feature.
But there is no guarantee that the functionality won't disappear altogether. I'm sure we'll eventually do it right, but I don't like our current implementation, and I'm definitely not assuming responsibility for making automated migrations to any new functionality. So this is "use at your own risk".
It was implemented before we had packs and is neither properly wagn core nor a pack, but an "old_module". I hope (but don't promise) to port the code to a pack before long.
Sadly, I don't think it will be straightforward with Google maps docs. It's just complicated stuff.
Thanks! I'll let Peter know and we'll decide whether to give it a go. Is there a Wagn that's using it I can look at?
this was used by the sustain hawaii sites at some point but is not currently in use afaik.