[OSM-talk] TAG-Suggestion: highway:trailer_shipment

[Ulf Lamping]

Am 16.01.2010 10:16, schrieb Carsten Moeller:
> Yes, I do agree. We should have tags describing short and long
> distances. The latter is possibly best expressed by using relations.
> Yes, there are already tags for our problem:
>
> highway=service
> amenity=ferry_terminal (if it allows cargo=vehicle)
> ferry route (as tagged and displayed already on the maps)
> amenity=ferry_terminal (again with cargo=vehicle)
> highway=service
>
> But this kind of tagging is hardly parsable. In case of routing, I don't
> want to collect all highway=service in the topo.

Sorry to say, if you don't take highway=service ways into account, your 
whole routing program gets very certainly a lot less useful to a lot of 
end users anyway.

> For route=ferry or
> rail=railway I can distinguish if they are subtagged by motorcar=true or
> not. As a consequence the highway=service then should be subtagged with
> sth. like "ferry-link". But this guides me to my first approach again.
> In my opinion, it should be as simple as possible.

That's true. But it should be as simple as possible for the mappers (as 
long as it's somehow usable for routers) :-)

If you say "the mappers have to improve tagging, otherwise I won't be 
able to write a router" I'd say "write a better router". It's not 
because I don't like you, it's because I know that half of the mappers 
won't do it anyway and you'll just end up with a router not working in a 
lot of situations.

> I'm afraid, only few
> people will follow this tagging pattern and we'll end up in a forest.

That's no news, regardless of what we'll discuss here ;-)

> Once again, the main problem is the parsing itself. In case of the upper
> example you will have to analyze relations in a second step. If you
> tagged them directly It's just a one shot parsing.

If you don't want to analyze relations, you will also miss other 
required stuff (e.g. turn restrictions). A router not analyzing 
relations has no future IMHO.

> Another problem, as I've already mentioned before, are the connections
> (even same nodes) between railroads and streets. This is a annoying and
> kills the ability for OSM to route satisfyingly.

No, it doesn't ;-)

Regards, ULFL