[OSM-talk] zones for motorway/in town/outof town?

Lester Caine lester at lsces.co.uk
Thu May 21 08:47:36 BST 2009

Guenther Meyer wrote:
>> So while discussing HOW the default speed for roads are calculated is
>> important, can we not simply apply that speed without adding another
>> layer of complexity?
> I wouldn't do that, because it's a derived value depending on a lot of things 
> like road type, time of day, weekday, construction sites, ...
> ok, you might add this value additionally with a special tag, to give a hint 
> to routing applications.
Why? maxspeed IS that tag
The fact that some roads may not be suitable for DOING the maxspeed is 
another matter, and would benefit from an additional tag, but maxspeed 
is legally defined in most countries - and you do not need to have signs 
up to tell you what it is - that is if you have passed a driving test ;)

> but there are more applications than just routing, to  which that data may be 
> useless.
Does that matter?
maxspeed is already defined and exists
Additionally there is a page for speed limits against highway tag and I 
remember a discussion about low speed limits in traffic calming areas 
which proposed an alternative to highway=residential for those areas, so 
the type of road is already included in defining the default maxspeed.

> on the other hand the speed limits are defined values (at least in every 
> country I have been so far...).
What I'm failing to see here is the REASON we need to add another set of 
area definitions simply to do with speed when that information is 
already well covered in existing tags - if they are used properly?

Lester Caine - G8HFL
Contact - http://lsces.co.uk/wiki/?page=contact
L.S.Caine Electronic Services - http://lsces.co.uk
EnquirySolve - http://enquirysolve.com/
Model Engineers Digital Workshop - http://medw.co.uk//
Firebird - http://www.firebirdsql.org/index.php

More information about the talk mailing list