The problem occurs, when using the commands "Smooth geometry" or "v.generalize.smooth" in QGIS.
The water level contains some hard edges, which wouldn't look like this in reality, so I want to smooth those edges a little bit, using the commands I mentioned above. It gives a nice looking result, but unfortunately includes invalid elements.
I uploaded the files at wetransfer: https://we.tl/45WV0KpTLx
- water_level_HQ30_diff.shp: original file without validity problems
- water_level_HQ30_smooth.shp: smoothed with v.generalize.smooth (Grass Gis 7 command)
- water_level_HQ30_smooth_native.shp: smoothed with "Smooth geometry" (QGIS geoalgorithm)
How can I get this vector layer smoothed without getting invalid elements?