[mkgmap-dev] Map display squeezed horizontally

Tue Apr 23 00:12:30 BST 2013

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