On Tue, 12 Oct 2010 22:19:15 +0200, Frederik Ramm <[email protected]> wrote: > Hi, > > 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 > implement. 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. Matthias _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
