[mkgmap-dev] Routing

Fri Jul 16 09:27:13 BST 2010

2010/7/16 Marko Mäkelä <marko.makela at iki.fi>:

> Have you tried splitting the tiles further? In my experience, mkgmap
> does not always flag errors when exceeding some Garmin limits, and you
> can end up with all sorts of breakage (including routing errors in some
> areas) when you generate too large tiles. The OSM data set has a
> tendency to grow. A year ago, 2 or 3 tiles of Finland was enough. Now I
> am splitting it to 6 tiles.

...just found the Problem:

My build Process (for a multi-layer map) includes setting the main
layer (roads, POI) to transparent using gmt.exe because mkgmap somehow
doesn't  manage to make this singe layer transparent.
gmt.exe seems to kill the road-searching information in this layer's
gmapsupp.img.
When I then compile all gmapsupp.img files into one with mkgmap, its
not included...

Did someone else also experience this transparency problem?

Maybe we'll have some more elegant way of creating multi-layered maps
with mkgmap at some point in the future.

-Martin