[OSM-talk] Subway station vs. subway entrance

[Frederik Ramm]

Hi,

 > I think, for navigation it's enough, to bring people close to the
 > destination; so that they just have to open their eyes to see the
 > entrance.

 > It's not possible, and doesn't make sense, to get people to the exact
 > spot via gps, if they want to find something.

You should not limit your thinking to GPS usage. People may want to 
generate written instructions: "How to reach 123 Bramble Road by 
subway". Provided we had a routing algorithm and provided we had the 
information about were 123 Bramble Road is - both will some day be in 
OSM for sure - then it is absolutely necessary to be able to guide 
someone *at least* by saying: "Take the so-and-so exit from the subway, 
then turn right onto Bramble Road".

This is a completely GPS-less scenario, and one that simply doesn't work 
if you do not know where the exits are. And even if it is the other way 
round ("how to reach the subway from 123 Bramble Road"), then if you 
just guide someone to some imaginary centre point and tell them "now 
look around you and find a subway entrance", they may already have 
passed a number of better suitable entrances.

 > when you try do do it this way, you have to be consequent, and have to
 > do gps navigation in the subterranian areas of subway stations,
 > shopping malls, ... which is not possible.

No. And even for mapping purposes, it wouldn't be necessary to have 
underground GPS tracks as people who are familiar with the station 
layout can probably draw everything that is required from the top of 
their heads, given proper mapping of the entries.

 > that's one problem I have with osm. it's a great project, but it
 > seems, that people here like to tag every little dust particle.

I don't have a problem with that, as long as stuff is tagged in a way 
that lets me filter it automatically.

 > you can't guide someone to his destination only by looking at the
 > map/navigation-device. if you like to do that, you have to tag also
 > every pole standing around...

People have started tagging traffic lights, post boxes and public 
telephones. I have no objection to that. In fact I would also be very 
interested in maps of underground drains and canals ;-)

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'