[OSM-talk] zones for motorway/in town/outof town?

[Lennard]

Radomir Cernoch wrote:

> The idea is not to create a node "here starts city" and a node "here
> ends the city". The idea is to create a polygon which defines the border
> of 50 km/h speed limit. The problem of forgotten "end node", which
> causes cities to leak all over the planet, does not apply.

Now we have an urban area, with a circular road with maxspeed=50, and 
streets and cul-de-sacs left and right of that road with maxspeed=30 
zones. And that is just a simple example. The polygons are going to be 
complex in some cases.

>> The problem now is that you cant actually work with polygons as for
>> example a motorway could pass over a zone-30.
> 
> Sorry, I maybe didn't make myself clear. "Polygon" rules do not apply
> for motorways. Is there any country, where a highway inside a city has
> different speed limit from the highway outside of the city? Even if yes,

Yes.

> this can be specified in the set of country-specific rules...

Don't focus on the highway-in-city bit. Focus on the "$random_road_type 
with a different maxspeed bridges over (or tunnels under) a zone with 
another maxspeed" bit. You'll have two zone polygons overlaying each other.

> I can imagine a situation, where a normal 50 km/h road goes through the
> middle of a zone-30. Then there are two options:
> 1) You split the zone-30 polygon into 2 polygons.
> 2) You tag the 50 km/h road with "maxspeed=50".

Right, exactly the scenario I mentioned at the top of this msg.

-- 
Lennard