[OSM-talk] Routing on OSM maps on a Garmin device

[Maarten Deen]

On Tue, 15 Jun 2010 15:20:07 +0200, Lambertus <osm at na1400.info> wrote:
> On 2010-06-15 01:53, Liz wrote:
>> On Mon, 14 Jun 2010, Maarten Deen wrote:
>>> Does anyone have similar experiences, and maybe an explanation why
this
>>> happenes? Are the OSM maps too detailed for a simple device like this
to
>>> calculate?
>> Using a separate *set* of maps for Australia, I have had trouble with
>> calculating a route that crossed a border from one map in the set to
>> another.
>> The distance involved is not the problem in this case, but the
existence
>> of the border.
> 
> That could be a result of the method used to split the data. If you use 
> the Mkgmap Splitter tool then crossing borders should be possible, but 
> using Osmosis et al won't.

And it would explain it only partly. I know the Garmin map does extend
some distance into Germany in detail, but it also covers Europe in low
detail. So you would expect to get some form of route, albeit not very
accurate, and the device would not show you on the road.

But it does not explain why I got a route to my first waypoint from the
start (likely to be outside of the Garmin map, but I'll have to check that)
and not when, after I was well and truly in Germany and on the OSM map, I
chose not to follow the route and it could not recalculate the route. Nor
does it explain why I got a route in "economic route" mode and not in
"fastest route" mode.

And the maps from All in one Garmin Map are also made with Mkgmap, so the
problem shouldn't occur anyway.

Regards,
Maarten