[Openstreetmap-dev] Streets in GPX

immanuel.scholz at gmx.de immanuel.scholz at gmx.de
Thu Sep 22 11:07:52 BST 2005


Hi again,

> However, is this the most efficient way in terms of file size? e.g.

In terms of uncompressed or compressed file size?
Do the compressed files really differ in size (by say, more than 5 perc.)?


[first version]
> <trk>
> <id>505021</id>
> <name>Lodge Road</name>
> <extensions>
> ... key value stuff
> </extensions>
> <trkseg>
> <trkpt lat="lat1" lon="lon1"/>
> <trkpt lat="lat2" lon="lon2"/>
> </trkseg>
>
> <trkseg>
> <trkpt lat="lat2" lon="lon2"/>
> <trkpt lat="lat3" lon="lon3"/>
> </trkseg>
>
> <trkseg>
> <trkpt lat="lat3" lon="lon3"/>


[second version]
> <trk>
> ...
> <trkseg>
> <trkpt lat="lat1" lon="lon1"/>
> <trkpt lat="lat2" lon="lon2"/>
> <trkpt lat="lat3" lon="lon3"/>
> ... etc ...

This is definetly what GPX is think of how street data should look like.


If it is easy to convert the first version to the second, it could be done
in the code that is querying the database and make the GPX-document.

But if the line segment data is not in exactly the first version (e.g. the
line segments are unsorted), it is not trival to convert the versions into
each other.


Ciao, Imi.






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