On Tue, 28 Jul 2009 08:11:21 +1000, Roy Wallace <waldo000...@gmail.com> wrote: > On Mon, Jul 27, 2009 at 9:47 PM, John Smith<delta_foxt...@yahoo.com> wrote: >> --- On Mon, 27/7/09, Roy Wallace <waldo000...@gmail.com> wrote: >> >>> I think the bridge should be tagged. >> >> There was an overwhelming response on the main talk list that this be >> tagged as maxheight on the way that has the restriction, ie you can't go >> under the bridge unless you are under x metres. > > There are two issues here: 1) what should be tagged and 2) what should > it be tagged with. > > For 1), what should be tagged? Definitely the bridge. For two reasons: > firstly, clearance under a bridge is an attribute of the bridge.
Wrong. It is an attribute of the ways below the bridge. because: 1) Multiple ways below a round bridge have different maxheight-values (happens in my place all the time) 2) Not only bridges have maxheight but also parking-lots, tunnels, ... 3) The way below the bridge does not intersect the bridge at all. There is no reference from the street below to indicate that there is a bridge at all. You would have to analyse the location and vector of all other ways in the map as one of them could be a bridge and you would have to do that for each and any way-segment you want to evaluate for routing. Bad idea. > For 2), what should it be tagged with? I concede that a bridge tagged > with "height" could be misinterpreted (as the actual height of the > bridge or bridge construction), as could "maxheight" (as referring to > a restriction involved with traveling on top of the bridge). We have tags "maxheight", "maxwidth", "maxspeed", ... "ele" and "height" that are in wide use and have a well established meaning, well documented in the wiki. Period. _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
