can someone explain a few things about the way boundaries work, and their relation to the is_in key?
as far as i can tell, when a location (say the suburb of balham, in london) is added to the map, the is_in tag needs to be set, multiple times. in this case, it would be set as follows: is_in:Westminster (...i think) is_in:greater london is_in:england is_in:united_kingdom is_in:British_Isles is_in:Great_Britain is_in:Europe ...etc. which seems counter-intuitive, not to mention requiring huge amounts of work. do we set this for every item - roads, churches, supermarkets,....thousands of other items? is there anything underway to enable OSM to calculate where an object is, based upon knowledge of administrative boundaries - after all, they are only a polygon-shaped bounding box? if i set is_in of balham to london, and the is_in of london to england, does osm know that balham is therefore in england, by cascading the is_in values? and so on, for as many levels as we define? my second, related, point concerns boundaries that coincide with coastlines: do we need to trace over the coastline of a country/city/suburb to define an unbroken loop for each administrative areas, or can OSM work out for itself that the coastline forms the rest of the boundary? what about if the entire boundary is defined by coastline? are these questions only relevant if and when items are automagically aware of their location? thanks for any help _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
