[mkgmap-dev] Routing (and other) woes

Sun Feb 22 11:25:16 GMT 2009

Michel Marti wrote:
> * Two of the motorway-links there look like residential roads on the
>   device
> * way 4987473 is labeled '67' although there is no such ref or
>   name for this way in the OSM data
> * The way 10864230 (highway=secondary) is labeled "Ramp" on the garmin
Investigating a little more, i noticed that those problems actually show 
up on the built-in map (City Navigator Europe NT 2008) and not the 
mkgmap-generated ones... I somehow accidentally switched maps before 
examining the area ("blush"). Sorry for the noise.

> I also noticed that when taking a different route as the one suggested 
> by the device, it takes much longer for the garmin to recalculate the 
> route than with the built-in map.
This claim still stands. I just saw that at least one other person 
noticed this too:

http://wiki.openstreetmap.org/wiki/Talk:Mkgmap/routing#The_.27tolerance.27_setting_for_following_the_expected_route

> As a side effect, in those two areas, the garmin omits some
> turn-instructions.
I can still see this behaviour for motorway-entrances and exits. Maybe 
there are some OSM-Tags missing for the areay I tried?!? For exits, 
there is a tag called 'highway=motorway_junction' (whose ref tag should 
hold the exit-number), but it seems that mkgmap ignores such nodes 
completely.

Cheers,

- Michel