[OSM-talk] New contributor query

Etienne Cherdlu openstreetmap-L at gj0.net
Tue Apr 25 13:33:50 BST 2006


On 4/25/06, Steve Chilton <S.L.Chilton at mdx.ac.uk> wrote:
> I am a new contributor of data to OSM, having found a redundant Garmin
> eTrex Venture GPS unit in our department, and having massive interest in
> mapping, and community mapping in particular. After considerable
> experimentation I have uploaded a couple of GPX tracks to test system
> and done simple editing to learn the online editing tool. Question I
> have is what to concentrate on. I live/work in N London (Enfield) and
> there is masses of the area to survey, which am happy to do by bike.
> However, should I bang out as much GPS data as possible and upload and
> convert to segments to get raw data complete as soon as possible, or
> should I systematically make ways as I go, code with appropriate tags,
> etc (and edit the existing local data where necessary) to produce
> totally logical data from start?

I use a bike mounted GPS unit and I try to work over an area fairly
systematically.  At least ,I pick an area between a couple of major
roads and try to cover it as thoroughly as possible.  Always turning
left is a very good strategy for urban residential areas (unless you
end up back where you started).  I also work on the basis that I will
never re-visit a place, so I never leave an unvisited route for later
(especially if it is at the far end of a 3 mile country lane).

I keep my expeditions to about 2 hours because this is both the limit
to the memory in my GPS (at 1 point per second) and the limit to what
I can remember about where I have been.  I use a camera to record the
name of each road and I also snap major road signs and anything else
interesting or significant along the way (churches, museum signs,
etc).

Back at my desk I try to upload and tag everything as soon as possible
as I find that my recent memory helps with detailed interpretation of
the track logs.

I create segments and ways and tag everything as I go rather than
revisiting the data later when my memory is not so fresh.

>My natural instinct for order is the
> latter. It is also evident from the SVG output that I have seen and from
> Nick's dev website output
> (http://nick.dev.openstreetmap.org/index.php?lat=51.6666667&lon=-0.06666
> 67) that logical coding is vital to produce meaningful output, which I
> think is really getting close now. Second question is that I have
> scanned the help pages and can't find a guide to codeifying the data for
> optimum usefulness - is there one?

Yes, see http://wiki.openstreetmap.org/index.php/Map_Features for a
pretty comprehensive scheme.  The applet is unhelpful in suggesting
the use of class tags which I consider to be pretty much obsolete now.
 I use JOSM for editing.  I never use the applet - its too slow.

> I would like a definition of what
> should constitute a "way". Is the mimimum classication of ways that you
> create to use the "default" dropdown menu's worth of 4 road types
> (motorway to minor road) and 4 non-road types?

The definition of a "way" is a little unclear at the moment.  Strictly
it is an *ordered* collection of segments.  There has been some
discussion about how a way should be used to represent roads that
split or contain roundabouts, but I haven't seen any conclusions or
recommendations yet.

There is also the question of whether one road (say, the M25) should
be one 100 mile long way or made up of several shorter ways.  The
former isn't practical at the moment...

>Perhaps one outcome of
> IoW and Manchester efforts could be further documentation? Third less
> important question. Can you find out and contact people that are mapping
> near you to share experiences, ensure dovetailing, etc?
>I notice that
> Barnet area is deeply detailed. Can I contact the mapper(s) to
> collaborate on joining Barnet to Enfield as we progress?

The Community portal on the Wiki is the place for this at them moment
(http://wiki.openstreetmap.org/index.php/OpenStreetMap:Community_Portal).
 If there isn't a page for Enfield then you are welcome to create one.
 Also I see that user Welshie has done some work on the A110 and is
probably responsible for the work that you can see
(http://wiki.openstreetmap.org/index.php/User:Welshie).

--
Etienne




More information about the talk mailing list