[mkgmap-dev] Runways on highways

Wed Jun 9 07:26:30 BST 2010

On Tue, Jun 08, 2010 at 10:57:58PM +0100, Dave F. wrote:
>> I don't know. Ice roads
>If you mean roads with ice on them then, well... all roads get icy.

I mean lakes with 20+ cm ice cover on them so that you can drive even 
heavy trucks over them for a few months in the winter. They would be 
ploughed too. Some are several km long, some are much shorter. There is 
one across this water:

http://www.openstreetmap.org/browse/way/18738651

but the ways (even to the coast) have not been surveyed yet. Outside 
winter, you would have to take the boat or a detour.

>If you mean bridges that raise up to allow traffic to go underneath 
>then no, it's not - it's always a lift bridge.

Some lift bridges are almost stationary. This one is raised every 10 or 
20 years for maintenance:

http://www.openstreetmap.org/browse/way/4727228

The lift bridge section, the barriers or the control/machine room 
building have not even been marked in OSM.

>Have you heard of Garbage In, Garbage Out? If the tags put into in OSM 
>are inaccurate then the info going into any program, including mkgmap, 
>is going to be garbage.

Sure, I have heard of it, and I have no trouble editing obviously wrong 
map data, using common sense of how things usually are built in my 
country.

>The best I can think of at the moment is to tag is as a highway, which
>is what most people will regard it as, but with barriers at the relevant
>points that have access=* tags & any timings that are available.

I would not map 'mobile' objects (other than gates and such, which are 
attached to some rail fixture or a pivot point). For example about here

http://www.openstreetmap.org/browse/node/285878811

there is a connection between the highway=trunk and highway=secondary 
that is blocked by a wall of conrete blocks. This would be near the NE 
of the temporary runway. There is another similar connection at the SW 
end, between the highway=motorway and the highway=secondary. For the 
duration of an exercise, the concrete blocks would be moved across the 
ref=5 motorway or trunk road, diverting cars to the highway=secondary 
ref=140. BTW, the motorway lanes that are tagged oneway are not 
separated by a greenfield, but the whole area has been paved.

I don't think that the aeroway is completely wrong, but I agree that 
ways can't be highway and aeroway at the same time. One idea could be to 
define a relation on the ways (in the original problem, a 
highway=service loop and the straight section of highway) to mark the 
temporary air force base.  I will seek for feedback on the Finland 
forum.

	Marko