[OSM-talk] Should Bridges be independent of their ways?

[Lester Caine]

Roy Wallace wrote:
> On Tue, Sep 22, 2009 at 12:20 AM, Anthony <osm at inbox.org> wrote:
>> A bridge should probably have its
>> own geometry.  And if a bridge has its own geometry (polygon or line and
>> width) and a layer tag you don't even need the relation, do you?  Anything
>> in the area of the bridge with the same layer is located on the bridge.
> 
> I like the idea.
> 
> BUT I shouldn't have to measure the bridge to be able to indicate that
> a section of way(s) goes over a bridge.
> 
> Using an area to mark a bridge in this way should be *optional*, in
> the same was as a POI can be marked as a node or an area. Therefore, a
> "bridge" relation would still be useful to indicate that multiple ways
> share a bridge, for when the bridge geometry is unknown.

Which is exactly the same rule as applies elsewhere. A car park can 
exist simply as a POI tag, or as fine detail, perhaps even with parking 
bays. The point is to make things transparently scalable. At the 
'county' level you don't need the shape of the car park, just a tag to 
it's presence so you can indicate where they are. Same with any object?

-- 
Lester Caine - G8HFL
-----------------------------
Contact - http://lsces.co.uk/wiki/?page=contact
L.S.Caine Electronic Services - http://lsces.co.uk
EnquirySolve - http://enquirysolve.com/
Model Engineers Digital Workshop - http://medw.co.uk//
Firebird - http://www.firebirdsql.org/index.php