[OSM-talk-ie] Completeness/usefulness

Dermot McNally dermotm at gmail.com
Tue Jun 17 19:57:59 BST 2008

2008/6/17 Paul Cunnane <paul at cunnane.net>:
> I've posted before on the topic of completeness, and I think we're all
> agreed that an important milestone will be the completion of the N-road
> network, followed by the R network. This will give the basis for fairly
> useful navigation to most of the country.

Agreed. As long as we're on the subject, I'm happy to report that I
have surveyed, but not yet mapped, the last piece of the N71 (Bantry
to Kenmare). It will still need confirmation of route within Tralee.

> The question becomes, what degree of completeness is required to truly
> enhance the usability value of the Map? When I posted before I had
> talked about quartering off geographical areas and mapping them to
> completion. Realistically, though, the sheer density of the road network
> in this country means a line has to be drawn somewhere - not every
> boreen is needed to make the map useful.

It could be interesting here to consider what Navtech (as it was then)
did in the area of mapping Ireland. It was along the following lines:

* Dublin and Belfast (and connecting route? can't remember), each one
gradually growing.
* Gradual addition of additional urban centres, biggest first.
Connecting roads provided in all cases to a level where a reasonable
route was possible from any one mapped urban centre to any other.
* Fairly suddenly, all this was augmented by the full national and
regional network, plus locations for all towns and villages along
those routes.
* Detailed coverage for rural areas was added all in one go, but the
level of detail (parkland overlays and other such polish) crept up

In our case we have a mix of detail levels that has arisen in a more
haphazard way. Your systematic mapping exercise is laudable, but we'll
need a lot more mappers before we'll cover the whole country that way.
IMO, National and Regional roads get you most of the credit. There are
strategic local roads that are well worth adding, and it's easy to
spot them - these would be roads that represent shortcuts on journeys
between two places of significance and whose quality is such that it
would be reasonable for a navigation application to route people down

> I've decided to pick a personal benchmark for completeness, for now: I
> have an AA road atlas that shows all roads down to what we might
> describe as the "tertiary" classification, and I'm aiming to get Mayo
> mapped to that level of detail.

Good call. That sounds along the lines I've outlined above. Some
tertiaries will be more dispensable than others. Is Mayo CC signing
L-roads yet? If so, have you been collecting them? I've taken to doing
this with a voice recorder.

> The price of fuel is starting to bite, though: the weekend's mapping
> exercise took 311km of driving.  :(

I know how you feel. I took the long way home from Belfast on Friday.
In doing so, I mapped the A3 from Moira through Portadown (including
M12), Armagh, Monaghan and various Regional roads in Co. Cavan. The
missing A3 had been annoying me for a while.


Iren sind menschlich

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