[OSM-talk] [tagging] Feature Proposal - RFC - Clearance

[Aun Johnsen (via Webmail)]

On Thu, 30 Jul 2009 14:17:22 +1000, Roy Wallace <waldo000000 at gmail.com>
wrote:
> On Thu, Jul 30, 2009 at 12:00 PM, John Smith<delta_foxtrot at yahoo.com>
> wrote:
>> --- On Wed, 29/7/09, Aun Johnsen (via Webmail)
<skippern at gimnechiske.org>
>> wrote:
>>
>>> I have made a proposal for a tag
> ...
>> I think this will only serve to confuse, no where on the maxheight wiki
>> link you provided does it say it's a legal restriction, if anything it's
>> exactly the same thing you're just giving people the option of picking
>> tags so half the system will have maxheight used, and half will have
>> clearance and the routing software will end up with twice the work for
no
>> benefit.
> 
> True, maxheight currently does not specify the reason.
> 
> So the question is, is there a need to differentiate between different
> "kinds" of maxheight? Surely this issue has come up before in relation
> to other keys?
> 
> If there is in fact a need to differentiate, what's the most common
> practice? For example, "maxheight:physical=*" and "maxheight:legal=*"?
> Just throwing ideas around, but you would first need to demonstrate
> that "maxheight" is not sufficient.
There area also other possible usages of a clearance tag, such as the free
sailing height under a bridge, the height of a footway tunnel and probably
much more. Since many countries have two different signs for max legal
height and max physical height, and its usages can be very different, why
not allow this in tags?

By saying that there is no difference between maxheight and clearance is
for me the same as saying there is no difference between highway and
cycleway, tourism and historic. 
-- 
Brgds
Aun Johnsen
via Webmail