[mkgmap-dev] Missing ways part 1

Mon Oct 18 18:15:29 BST 2010

I have noticed some missing ways in my Garmin maps. I investigated, as
follows. I downloaded the France extract from Geofabrik in .pbf format;
used osmosis-0.37 to extract a bounding box, bottom=49.4 left=1.3
top=51.3 right=4.4; and ran splitter-r123 on the extract with
max-nodes=1500000. This is the resulting areas.list:

63240001: 2301952,141312 to 2347008,206848
#       : 49.394531,3.032227 to 50.361328,4.438477

63240002: 2301952,59392 to 2347008,141312
#       : 49.394531,1.274414 to 50.361328,3.032227

63240003: 2347008,141312 to 2371584,190464
#       : 50.361328,3.032227 to 50.888672,4.086914

63240004: 2347008,59392 to 2392064,141312
#       : 50.361328,1.274414 to 51.328125,3.032227

I loaded each .osm.gz tile into JOSM in turn. This takes a few minutes,
and JOSM is very slow until you zoom well in. It needs about 1GB memory.
[This generated many thousands of messages on stderr, along the lines of
"WARNING: Normalizing value of attribute 'version' of element
552,829,105 to 1, API version is '0.5'. Got 0." Why does splitter
downgrade the API to v0.5?] I found that way 31799814 (79 nodes) was
missing. This is a 57km section of the high-speed railway line between
Lille and Paris. The way should have been split between tiles 63240002
and 63240004. The way is present in the file which was input to
splitter. Why does the way go missing?