[QGIS-Developer] Split parts tool creates invalid polygons

[Andreas Wicht]

Hi,

> The split parts tool creates invalid polygons according to GEOS check
> validity. This issue seems to have been discussed two years ago
> https://issues.qgis.org/issues/12799 but it still persists today in master.

Also see last years' discussion:
https://lists.osgeo.org/pipermail/qgis-user/2017-May/040007.html

> To reproduce:
> 1. Create a memory layer with multipolygon type
> 2. Add a polygon
> 3. Split the polygon using split parts
> 4. Use the vertex tool to move the parts apart, in order to avoid issues
> with polygon parts sharing an edge or vertex
> 5. Run check validity
> [...]
> Should I reopen the ticket? I don't see how this tool can be used without
> ruining the features.

I think that is a very good idea. Currently the more robust way is to go with
Bernhards' DigitizingTools version of "Split Features".

Andreas