[Talk-ca] GeoBase to OSM attribute mapping.

[James Ewen]

On Sat, Dec 27, 2008 at 9:45 PM, Steve Singer <ssinger_pg at sympatico.ca> wrote:
> On Fri, 26 Dec 2008, James Ewen wrote:
>
>> Just looking at some attributes...
>>
>> The alleyway/lane is currently mapped as highway:service. I would
>> suggest that highway:service is more appropriate. Here's the
>> description for a sevice road:

Fat fingers... alleyway/lane is currently mapped as highway:living_street.


>> Rapid Transit is currently mapped to highway:bus_guideway. I'm
>> thinking railway:light_rail, at least in Edmonton, our rapid transit
>> system is a light rail transit system. Perhaps other areas of Canada
>> have a rubber tire based guided transit system.
>>
>
> Are Edmonton light rail routes tagged in the NRN as "Rapid Transit" or not
> counted as roads? I don't see anything in the BC dataset tagged with this
> class (I don't see anything in the BC dataset tagged with rapid transit)

Edmonton's LRT is not in the NRN... should have looked first! 8)

Is there a way to find specific examples of road classifications? We
really need to look at real world examples of what Geobase tags map to
so that we can confirm specific map attributes.

> I don't think we can assume rapid transit is rail. Ottawa has a tire/bus
> based transit system with some dedicated bus only highways. I suspect this
> shows up elsewhere. The definition in the NRN feature spec says "A
> thoroughfare restricted to public transit buses".

Hmm, the OSM definition of bus_guideway goes beyond being just a
highway that is restricted to bus traffic only. It appears to be
almost like a railway line, where the driver could set the cruise
control, and wander away from the wheel. (Of course this would
probably be grounds for dismissal!). A restricted use highway for
rapid transit use could probably still be classified as
highway:whatever_level, access=no, psv=yes.

>> In Alberta, we haven't tagged anything as highway:motorway. Our top
>> level tag is highway:trunk. This GeoBase/OSM project could work to
>> unify the tagging across the country!
>
> Yes unified tagging across the country is something we should be working
> towards.
>
>>
>> What about Freeway -> highway:motorway, Expressway -> highway:trunk,
>> Highway -> highway:primary?
>
> Your differentiating between "Expressway" and "Highway" as I read the NRN
> feature map "2 Expressway/Highway" is a single feature code.
> You could do
> Freeway=>highway:motorway
> Expressway/Highway => highway:primary or highway:trunk

I think we're going to run into a problem, where OSM has a set of
attributes that don't match up with GeoBase. It was a number of years
ago that I was playing with the shapefiles from GeoBase... I had to
manipulate the attribute mapping table to try and get a decent map.
There were some weird tagging concepts that I saw.

When we move GeoBase data to OSM, and people decide that the GeoBase
tags don't match their concept of what the road attribute tag should
be, there will be conflicts... Another interesting thing to deal with.

I'm going to have to dig out some kind of tool for digging into the
shapefiles again to refresh my memory on what different tags are on
which roadways.

James
VE6SRV