[OSM-talk] [RFC] Deprecating the use of Tag:highway=stop in favour of Key:stop

[David Paleino]

On Mon, 24 Aug 2009 23:32:46 +0200, Renaud MICHEL wrote:

> Le lundi 24 août 2009 à 15:25, Lester Caine a écrit :
> > Adding an extra node does make sense, but probably needs a 'relation' to
> > the intersection as well? In any case the direction through this new
> > node is the critical piece of information? Tagging ways would require
> > that every section of a way is broken up. I'm thinking of some route
> > around here that have several intersections along them, many but not all
> > of which are compulsory stop along that single way. Simply adding nodes
> > on the correct side of each intersection would be somewhat easier to
> > implement, while currently these restrictions are not recorded.
> 
> How about simply creating a relation with those two nodes?
> 
> You have an intersection of two (or more) roads and when you come to that 
> intersection from one particular road (in one particular direction) you have 
> a stop. Then you add a node on that way before the intersection, then create 
> a relation (let's say of type=stop, or any more self-explanatory value) 
> where you have the stop node with role "stop_from" and the intersection with 
> role "stop_at".

Sorry, this is useless. We could just use highway=stop and teach routing
software that they're valid only if coming from a certain direction, decided on
a distance-from-nearest-junction basis. This is what we're (I am, at least)
trying to avoid: arbitrary placement of real-world nodes -- if we all had
1cm-resolution GPS units, then we would just use highway=stop. IMHO, YMMV.

> Such a scheme can be easily interpreted as: when you pass over a node 
> highway=stop that is a member of a relation type=stop with role stop_from, 
> then you must stop at the node of that relation that has the role stop_to.

No, you must NOT. In this case, you would stop in the middle of the
intersection. A stop signal instructs you to stop *before* the intersection. :)

Kindly,
David

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