Gerd Petermann schrieb: Hello Gerd,
47.15 5.75 55.15 15.15
This is a lot smaller than the areas covered by the almost empty tiles. Even more, I am splitting the contour lines into parts, none of them consisting of more than 2000 nodes, and then I am using osmosis to cut them to the shape of Germany. I have to use osmosis' parameter completeWays=yes when I am doing this, but even if 1999 out of the max 2000 nodes of a contour line are outside the bounding polygon this should be no more than a few kilometers.
It's difficult to find the few data inside the huge and almost empty tiles without coastlines and cities, but at N 54° 42,0' E 13° 51,0' for example there are 3 ferry lines crossing: "Swinoujscie - Trelleborg", "Finnlines" and "Klaipeda - Kiel". All these lines leave the area my map should cover and seem to be included completely.
The question is only the bounding box, because that is used to calculate the tiles. So, maybe osmosis calculates a new bbox on the data in the files.
Yes, the problem was the bounding box, and it has to do with a change in Osmosis. Versions 0.40 and newer do not write a bounding box to the target file of a merge task if at least one source file has no bounding box. Version 0.39 wrote a bounding box to the target file in this case. My contour data does not include a bounding box, so merging the original germany.osm.pbf with my contour data resulted in a file without a bounding box.
In that case you should pass a bbox or polygon to osmosis.
This will of course eliminate the data outside the desired area, but even when using --bounding-box while merging the files with Osmosis 0.40 or newer there is no bounding box written to the target file! I think I will add a bounding box manually to my contour data. Passing a bounding box to the splitter does also work. Thank you, Michael