Map Germany: Important river Elbe missing

[Beejai]

After a Map update in 3/21 i realized that the River "Elbe" is missing between Hamburg and the north sea.

[lordfolken]

Yes the quality of the topology data is lousy. I have a process for extacting al the toplogy data from osm. However the challenge is to generate a reduced variant, so xcsoar stays performant.

[Beejai]

I Understand. But I still think it is more likely to be an Error or misconfiuration/process implementation issue. Because

1. In last years' Map there was more of the river there.
2. In the East of Hamburg the River is there. And the missing part in the west is much wider than the one that is visible in the east.

Please consider a few more details as todays devices are getting more performant, storage is sufficient and there is still the option to choose a HiRes or LoRes variant in the DL/Mapgen.

[Beejai]

In OSM the River is clear and wide. It seems unlikely for it to be erased by a detail reduction algorithm.

[lordfolken]

The osm dataset currently in use is more than 10 years old.

[lordfolken]

In addition some stuff comes from the cia db vmap0

[Beejai]

Ok. One thing remains. I'm pretty sure in 2019 the river was there. But I can't reproduce it any more. The old xcm is overwritten. And maybe it even changed with an XCSoar update and is no Topology issue at all.

Is there anything that can be done to get the most important VFR orientation Line in the DE HH Area back?

[Beejai]

Please consider looking into this. I can now reproduce the error. I generated a new map today... and now the west part of the river is there and the east is missing. So the other way around. If I load the map from 2021, It's again west missing and east is there. The (wide) River ends abruptly. So it can't be because of source data missing or detail reduction.