[OSM-dev] josm bugs and enhancement requests

Gabriel Ebner ge at gabrielebner.at
Fri Oct 19 16:10:02 BST 2007


On Fri, Oct 19, 2007 at 03:52:13PM +0200, Marcus Wolschon wrote:
> > If a subway entrance and a post box  
> > happen to be in the same spot, we still use two nodes (correct me if  
> > I'm wrong here, I assume this is so but I might be mistaken). If a  
> > country border ends exactly where the river is, we will usually have  
> > two ways using the same nodes, one for the river, one for the border  
> > - both using the same nodes.
> 
> So you also create 24 ways in the same place at a central tram-station
> because 24 tram-lines and bus-lines use that way?
> There is only 1 river and there is only 1 way in the real world.

But there are 24 _tram_lines_ on that way...

> > I think the main reason for this is easy separatability. If I want to  
> > draw the Karlsruhe tram network on its own, then I can just extract  
> > all railway=tram ways in the area and throw them into Osmarender. If  
> > people would tag their ways as railway=tram *and* highway=something  
> > at the same time, then It would be much more difficult to get a  
> > "clean" tram dataset.
> 
> You will have to edit it anyway because tram-lines are not
> rendered at the moment. Only the rails they drive on
> (would be a fairly useless map).

railway=tram _is_ rendered (at least on osmarender).

> Reasons against it so far:
> * It leads to errors. (In no editor will you see that there actually IS
>   a second way in that place. Thus you will not notice
>   missing parts of the second way)
> * It is difficult to edit and will stay unintiutive to edit at best.
> * it wastes space (why bloat the db if we don't have to?)
> 
> Reasons for it so far:
> * you want to be lazy in downloading parts of the map without
>   filtering you output

  * is unambigous (so what does the ref in highway=primary, railway=tram,
    ref=1 mean?)

In any case, I think it would be better to use relations[1] in this case.
That way you could just say that a tram runs on a part of this road and on a
part of that road, and you'd be done.  No need to fit tons of unrelated
informations into the way itself (why just the trams?  there are also cycle
routes, sightseeing routes, ...).

  Gabriel.

[1] Looks like someone already made a proposal for that:
http://wiki.openstreetmap.org/index.php/Relations/Proposed/Routes





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