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<p><font face="Helvetica, Arial, sans-serif">Hello.</font></p>
<p><font face="Helvetica, Arial, sans-serif">We are working with
SNCF, the french railway company, to provide pedestrian
navigation inside and around railway stations in the Greater
Paris area. A dedicated routing engine, which provides
indoor/outdoor navigation and supports area routing, has been
developed – this will be presented during SOTM in Heidelberg.<br>
<br>
In order to improve the user experience, we want to provide
walking instructions such as "take the exit 'Rue de Londres'" or
"Walk through the gate labelled 'Northern lines'" rather than
"Walk 75 metres then turn left". Our problem is that such
waypoints may have a different name depending on the direction
you cross them. The solution we used is to create, when there is
such an ambiguity, two destination_sign relations pointing to
the same 'intersection' member, one for each direction with the
'from' and 'to' members swapped. Here is an example at Juvisy
station : the entrance named 'Accès Danton' when walking in
(<a class="moz-txt-link-freetext" href="https://www.osm.org/relation/9471596">https://www.osm.org/relation/9471596</a>) is named 'Quartier Seine'
when walking out (<a class="moz-txt-link-freetext" href="https://www.osm.org/relation/9471597">https://www.osm.org/relation/9471597</a>).<br>
<br>
I wish to amend the Wiki to explain that destination_sign
relations can also be used for pedestrian and indoor routing,
not just at "crossroads". Does that require opening a discussion
in the discussion page, or may I just go ahead ?<br>
<br>
Now since the routing engine supports area routing, we need to
loosen some constraints on the members, that are documented on
the wiki and enforced by the JOSM validator :<br>
1/ allow areas for the 'from' and 'to' members, as in this
example : <a class="moz-txt-link-freetext" href="https://www.osm.org/relation/9722912">https://www.osm.org/relation/9722912</a><br>
2/ allow multiple 'intersection' members, so that multiple doors
can be referenced by a single relation – example in Gare
Montparnasse : <a class="moz-txt-link-freetext" href="https://www.osm.org/relation/9823029">https://www.osm.org/relation/9823029</a><br>
3/ allow multiple 'to' members, so that the same relation can
point to both a line and an area, and cover linear and area
routing (no example but I could create one).<br>
<br>
Are there objections to this proposal ? Do you recommend to open
this subject on the Discussion page or is it best discussing it
on this list ? <br>
<br>
Regards,<br>
Antoine.</font><br>
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