[OSM-talk] Missing structure

[Lester Caine]

Martijn van Oosterhout wrote:
> On Jan 18, 2008 3:42 PM, Karl Newman <siliconfiend at gmail.com> wrote:
>> I don't have any particular objections against your proposal (although it is
>> somewhat complex), but I still think geographic boundaries are the way to
>> go. Which do you think will happen first: Creation of boundaries and a way
>> to quickly query a point against them (or rather the reverse: given a point,
>> return the boundaries), or tagging of nearly every object in the database
>> with an is_in tag?
> 
> FWIW, with the coastline checker being basically done, I'm considering
> applying the same process to boundaries, a boundary checker. As a
> side-effect it will produce a shapefile of all the boundaries, which
> can be efficiently queried for is_in-ness...

The problem will be checking every boundary found near the object being 
inspected, which requires all of those boundaries to be complete and closed.
Working against an is_in key eliminates all of that processing when trying to 
find things and will work for boundaries for which the boundary data is 
incomplete. At some point in the future the is_in keys could be automatically 
build or corrected when a boundary is edited. However the automatic population 
would not be able to easily stablish that a particular boundary is within a 
larger on, at which point the is_in flag for the higher levels become even 
more important?

-- 
Lester Caine - G8HFL
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