[mkgmap-dev] routing

Tue Nov 25 13:20:04 GMT 2008

Hello Steve, all,

slowly coming back from an OSM break (sorry), I had a look today at  
how far mkgmap and routing has come. Great work!

So those mysterious TRE header bytes are just computed from the map  
id? An obscurity feature?

I compiled branches/nod and tried creating an img with:

$ java -jar mkgmap.jar --route --gmapsupp schoeneberg.osm

Correct? After modifying imgfmt.app.net.RoadDef.writeNod2 to return if  
node==null (that's the routing node), the map compiles. It loads fine  
on my Etrex Vista HCx, but routing doesn't seem to work. If I try to  
route, it routes me along the base map (unfortunately, there's a road  
in the base map near here).

I've traced the issue with the null routing node back to  
mkgmap.general.RoadNetwork.addRoad: in the cases where RoadDef.setNode  
isn't called, the coordList had length 0. This doesn't happen all the  
time, though. There's quite a few roads where coordList is non-empty  
and setNode does get called.

Any suggestions on where to investigate further? Are these empty roads  
to be expected?

(I've got the corresponding osm sources, but they're too big to post  
to the list; let me know if I should send them somewhere.)

Cheers
Robert