[OSM-dev] API 0.7+: Split node concept?
lists at julius-net.net
Tue Oct 12 21:41:31 BST 2010
On Tue, 12 Oct 2010 22:19:15 +0200, Frederik Ramm <frederik at remote.org>
> Chris Browet wrote:
>> I am wondering (I wonder a lot lately ;-)) if some have already given a
>> thought to the fact that nodes actually represent 2 different concepts
> Yes, this is something that has been discussed on and off for at least
> two years. I know because we mentioned in the first edition of our OSM
> book ;)
> Of course the "node" element would have to be kept not only for POI
> nodes but also for topology nodes (where two ways meet).
> Having geometries in ways would be much more traditional-GIS-like and
> would simplify many things. However your suggestion mixes in-way
> geometry with geometry by reference to nodes; and it has to because
> otherwise you lose topology. But this means you don't get the full
> advantages of either.
> A big potential problem I see is promoting and demoting nodes - you
> select and tag a "point" in a way, thereby creating a node; you later
> remove the tag from the node, thereby deleting a node. You let a road
> and a forest boundary share geometries, thereby creating proper nodes
> for each shared coordinate; you split them apart, deleting the nodes and
> creating two sets of points-in-ways.
> I see the basic idea but it all seems a but uneven to me, even ugly to
Maybe less ugly would be to have nodes just contain lat and lon and
introduce new point elements that need to reference a node.
That would also make it easier to put two different objects at the same
spot (like a mail box on a lamp post) as added benefit.
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