[OSM-dev] Area support

[Frederik Ramm]

Hi,

> How are you handling nodes shared by multiple ways? Embedding them N
> times, or outputting them first and referencing them?
> Same for ways referenced by areas (if that was the intention)?

I understand Stefan's idea to be a "read only" representation at the  
individual object level, so I assume that he wants the coordinates  
duplicated whenever a node is shared by multiple objects.

I say "read only" because obviously it has no topology, so it is  
unsuitable for loading it into an editor and changing the outline of  
the area there - the editor would have to upload *all* coordinates  
for the whole area even for a small change, and without node IDs the  
upload could not be matched to the database contents. We'd be editing  
shapefiles, basically, which is not something we want.

I agree that having coordinates "inline" would greatly simplify many  
application but this has nothing to do with areas (applies to ways  
and relations as well), but I also believe that our database should  
concentrate on the simple tasks like it does now, and a full geometry  
output could be delivered by another system further down the line.  
With osm2pgsql going in the direction of processing diffs, it is  
viable to have a PostGIS with current data loaded and allow all kinds  
of spatial queries returning standard PostGIS geometries.

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00'09" E008°23'33"