[mkgmap-dev] Turn restriction for highway=motorway[_link]

Wed Aug 4 15:55:33 BST 2010

El 04/08/10 14:04, Marko Mäkelä escribió:
> On Wed, Aug 04, 2010 at 09:07:27PM +1100, Hendrik Oesterlin wrote:
>    
>> "Carlos Dávila" cdavilam at orangecorreo.es wrote on 04/08/2010 at 20:14:50 +1100
>> subject "[mkgmap-dev] Turn restriction for highway=motorway[_link]" :
>>
>>      
>>> El 04/08/10 10:14, Hendrik Oesterlin escribió:
>>>        
>>>> Hello,
>>>>
>>>> I have some trouble to make turn restrictions work properly. I think
>>>> it is because mkgmap is failing to make them work if the highway types
>>>> are "motorway" or "motorway_link". The roads are behaving a bit like
>>>> "oneway=yes" in some directions. A very unpredictable thing.
>>>>
>>>> Is this a known behaviour? I am not jet 100% sure that the issue is
>>>> really triggered by the "highway=motorway". But maybe someone before
>>>> has already spend enough time to do all the trial-and-error testing
>>>> for this...?
>>>>          
>>> If you are using the dafault style, these lines in the lines file may be
>>> the key:
>>> highway=motorway {add oneway = yes; add bicycle = no; add foot = no }
>>> [0x01 road_class=4 road_speed=7 resolution 14]
>>> highway=motorway_link {add oneway = yes; add bicycle = no; add foot = no
>>> } [0x09 road_class=3 road_speed=2 resolution 16]
>>>        
>>      
>>> In my customized style I have removed add oneway = yes from the
>>> motorway_link line.
>>>        
>> Thank you for your hint! This is probably the problem.
>>      
> Wouldn't it be a problem of the source data? In my part of the world,
> motorway links tend to be entering or exiting the motorway at a very
> small angle, and are inherently oneway. Can you post a link to a twoway
> motorway link? Do you suggest that I should remove the oneway=yes from
> the default style?
>    
In most cases motorway links are separate oneway roads, but, at least in 
Spain, sometimes both directions share the same road. See way 70904729 
in the area below
http://www.informationfreeway.org/?lat=38.107106989860675&lon=-6.2724820671928425&zoom=15&layers=BF00F0
> Best regards,
>
> 	Marko
>
> PS: not all turn restriction traffic signs need turn restriction
> relations. For example, if you exit this parking ramp to the north
> http://www.openstreetmap.org/browse/way/46098413 you will see a sign
> that forbids a left turn. I did not add a turn restriction for it,
> because the way to the left is already oneway (forbidding the turn).
> Could it be that mkgmap or Garmin is misbehaving when you try to add
> such a "redundant" turn restriction?
>
> PPS: I have been using Google Street View (when available) when in doubt
> (or when I do not remember why I pressed the Lap button to create a
> waypoint when recording a GPS trace). It is a welcome addition to aerial
> imagery and other sources.