[mkgmap-dev] Splitter --overlap=50000 is the Magic Number?

Fri Sep 24 06:41:49 BST 2010

Hello,

I sometimes use the default Mkgmap style, editing some of the resolutions to
display at lower zoom levels.

I use the following splitter switches. I set the --resolution=12 as the
default style has natural=coastline [0x15 resolution 12]

java -ea -Xmx2500m -jar splitter.jar --geonames-file=AU.txt --mapid=40000001
--resolution=12 --no-trim --overlap=50000 myaustralia.osm

And this for Mkgmap.

java -Xms3500m -ea -jar mkgmap.jar --family-name=Mydefault
--series-name=MyDefault
--style-file=o:\garmin\mkgmap\resources\styles\default --nsis --net --route
--remove-short-arcs --drive-on-left --check-roundabouts --make-poi-index
--add-pois-to-areas --max-jobs --location-autofill:1 --tdbfile --index
--preserve-element-order -c template.args

What I have found is that only --overlap=50000 produces perfect maritime
borders fully around Australia anything other than 50000, gaps are produced
in the maritime borders. I have tried overlap 2000, 6000, 10,000, 15,000,
20,000 30,000, 49,000. 

Also for other styles I have used, I find --overlap=50000 works the best
also.

I use the default max nodes as this seems to work fine for me.

I tried decreasing the max nodes but then --overlap=50000 is way to high and
I then use --overlap=6000 but will have some gaps in the maritime borders.

Not too much of a problem as 50000 works perfectly for me, but I was
wondering if this maybe a bug.

This is what I use in osmosis to produce the MyAustrala.osm file.

bin\osmosis.bat -v --rx -b500 enableDateParsing=no file=planet.new.osm.gz
--bb top=-6 left=107.1 bottom=-48 right=163.5 completeWays=yes
completeRelations=yes --wx -bc500 file=o:\garmin\splitter\myAustralia.osm

Regards,

Markus_g