[OSM-talk] Topology

[Martin Spott]

Schuyler Erle wrote:
> * On 23-Apr-2007 at  5:12AM PDT, Frederik Ramm said:

> > And then uploading it to the server as two points which just happen  
> > to be at the same location? To me there's a world of difference  
> > between two nodes that just happen to be at the same position and two  
> > features connecting at the same node because it is (topo)logically  
> > the same node.
> >
> > For example, there's a railway line going over a bridge, and below it  
> > is a river.

> This reads to me more as an argument for z-index, or even altitude,
> than one for topology.

I'd say you still need to take the risk of errors due to varying
accuracy into account. If you don't, then one day you might loose all
your topology information when relying on z-axis/altitude information
(the same counts for the location itself),

	Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
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