[OSM-Talk-ZA] Tagging

[Mark Williams]

Hi Guys,

Perhaps in certain cases the physical functionality of the road may need to have higher priority than its network classification (as in Nics' example). I think we all know of roads that are unclassified or secondary etc. that seem to be "major" routes! This is possibly driven by the changing demography in S.A.

But, again, this is interpretation... And this is why we are always going to get people changing tags.

I, for one, am quite happy to tag the M39 as a primary road - it is a main feeder from Kempton/Tembisa to the N1 after all - and tag the M16 as a secondary road or even tertiary collector (using Pauls' interpretation).

Unless something can be clearly defined, there will be issues.

Paul has put forward a suggestion for classification which does make sense. I think we need more input from the regular "mappers" and users of maps.

Are we stirring up a hornet's nest?


  ----- Original Message ----- 
  From: Nic Roets 
  To: talk-za at openstreetmap.org 
  Sent: Tuesday, November 04, 2008 3:55 PM
  Subject: Re: [OSM-Talk-ZA] Tagging


  Hi Mark and Paul,

  I guess our standards are a bit open to interpretation, which is not necessarily a bad thing. It's relatively easy to get it right. It does not work for Rossouw Street M13 which carries a lot less traffic than Louis Botha M33. (And some idiot changed Hans Strydom in Pretoria to residential a few weeks back !)

  Paul, your system also looks easy except distinguishing between secondary and tertiary.

  I may be responsible for tagging the R104 as tertiary so that it stands out a bit better between the the M2, M4 etc. But if someone wants to change it (or and other road), I'll stick to the new values.

  The only thing that is important to me is that most routing software currently assumes that 'trunk' roads are faster than primary etc. And it's unclear if pedestrians and bicycles are allowed on trunk roads, so explicit tagging is best.




  On Tue, Nov 4, 2008 at 2:29 PM, Paul van Helden <paul at planetgis.co.za> wrote:

    Hi All,

    I'm have a similar question to Mark's. The words "trunk", "primary",
    "secondary" and "tertiary" implies a functional classification. A
    functionally classified road network should have each class
    (more-or-less) forming a closed network. The "motorway" class is not a
    functional classification, but a physical classification. For me, using
    the "motorway" class is acceptable because that is the way street maps
    are typically made: showing dual carriageways as the top class
    regardless of route designation or function. Anyway, only rarely in the
    case of underutilized dual carriageway roads is that an incorrect
    assumption.

    Defining "trunk" as N roads is making it a network classification. Since
    trunk roads are rendered in green and we want to see the national
    network on the map, regardless of function, it works.

    We have (at least) 3 different ways of classifying roads and these need
    to be blended into one classification. Our problem is also that we have
    to use the existing classes and get the OSM map to look like the street
    maps we are used to in SA. (In terms of colouring & the scales at which
    they display).

    The "tertiary" class is not mentioned on the tagging standards page. Yet
    there are a lot of them, many which (like trunk) "looks" right.

    My suggestion is to define the tag names as follows:

    Any freeway = "motorway" (physical classification)
    N roads (undivided) = "trunk" (network classification)
    Major routes linking into freeways and N routes, typically low numbered
    M & R = "primary" (main roads: combination between functional and
    network classification)
    Important routes linking into "primary" (main) roads (this sometimes
    will be a road without a R designation) or routes linking up populated
    places = "secondary" (network classification)
    Local collector roads, ie. residential roads that carry through traffic
    (often residential roads with sidewalks) = "tertiary" (functional
    classification)
    The rest = either "residential" or "unclassified".

    In terms of the correct naming of the above (for legends on customized
    maps) I would go for:

    Freeways
    National roads
    Main roads
    Secondary roads
    Collector roads
    Residential / other

    My suggestion for "tertiary" will invalidate many of the current
    "tertiary" roads - those that are not residential and are connecting
    populated places. A good example is the R104: Pretoria street connecting
    Bronkhorstspruit parallel with the N4.
    http://www.openstreetmap.org/?lat=-25.7542&lon=28.4227&zoom=13&layers=B000FTF

    Comments?

    Regards,

    Paul.


    _______________________________________________
    Talk-ZA mailing list
    Talk-ZA at openstreetmap.org
    http://lists.openstreetmap.org/listinfo/talk-za


  !DSPAM:40899,49105492100021795029775! 


------------------------------------------------------------------------------


  _______________________________________________
  Talk-ZA mailing list
  Talk-ZA at openstreetmap.org
  http://lists.openstreetmap.org/listinfo/talk-za


  !DSPAM:40899,49105492100021795029775!
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-za/attachments/20081104/15dc6f2a/attachment.html>