[OSM-talk] [tagging] Road crossings proposal - status?

[Dave Stubbs]

On Tue, May 6, 2008 at 10:28 AM, Steve Hill <steve at nexusuk.org> wrote:
> On Tue, 6 May 2008, Andy Allan wrote:
>
>  > [2] Another brilliant example of how people make themselves feel
>  > useful by doing the trivially easy bit, c.f. tracing from Yahoo with
>  > no intention of naming the roads.
>
>  I'm just going to voice an opinion (feel free to ignore it :) - putting
>  roads on the map by any means (e.g. wandering with a GPS, tracing Yahoo,
>  etc) is always very useful, even if one doesn't name the roads:
>
>  1. If you're doing something like route planning, you don't need to know
>  all the names of the roads - just knowing that you can get from A to B via
>  this road is useful (although some information about the quality of the
>  road is required so you don't direct HGVs up a tiny 1-track lane :)
>
>  2. If the road is on the map it becomes much easier for people who are
>  familiar with the area to fill in the details such as the name - no
>  equipment is needed (such as GPS), they don't need to get off their
>  backside and go out to walk/drive the road and there is next to no effort
>  in putting a name on a road if you know the area.  I can see that in many
>  cases, _users_ (i.e. people who just want a map and would otherwise
>  just be using Google) might be happy to add names when using the map
>  themselves, but aren't going to spend the time and effort tracing roads
>  from Yahoo themselves (for one thing this involves somewhat more
>  experience with how OSM works than just adding a name).

In my experience this isn't true -- the traced roads are rarely
entirely correct, rarely complete, and frequently don't split/join in
the correct way. So to name these roads you have to move roads, add
roads, split roads and combine roads. In general I find the tracing
rarely helps in editing an area after a survey, and you end up needing
a fair few skills to properly repair things. It's not unusual for me
to just delete all the tracing in an area I've surveyed and start
again from scratch.

Frankly any one can trace a road.... it's really simple -- editing is
a more involved process (at least with our present tools).


>
>  Chris Jones (who runs the Welsh language OSM) has been working on an AJAX
>  thing to make fixing road names easy without having to understand the
>  editors - I see this as a really good thing since it gets more people
>  contributing to the project, but it does require that the roads themselves
>  are in the database.


It requires they're in the database correctly. While in theory this
seems like a great idea, I don't think it's that simple in practice.
I'd be interested to see what he comes up with though.

Tracing has other problems... there's a possibility it actually
reduces new mapping as people mistakenly think an area is complete and
we're having to invest time and effort now in coming up with ways of
figuring out what's not really been mapped ie:
http://dev.openstreetmap.org/~random/no-names/

Notice how that really hasn't changed much from the map of what was
mapped before people started tracing. It doesn't really seem to be
acting as a stimulus as you might imagine.

Dave

PS. Please note I'm talking about tracing with no intention of
surveying yourself to collect on-the-ground data. The aerial imagery
is an incredibly useful tool in editing the map.