Bug report #13368
Difference tool generates invalid geometries
|Affected QGIS version:||2.8.3||Regression?:||No|
|Operating System:||Easy fix?:||No|
|Pull Request or Patch supplied:||No||Resolution:||end of life|
|Crashes QGIS or corrupts data:||No||Copied to github as #:||21420|
When using the Difference... tool on two layers with valid geometries, QGIS produces a layer with invalid geometries.
To reproduce, use the attached file:
i) open layers minizona13 and retalho
ii) use Check Geometry Validity to verify that there is no error before
iii) use Difference... with layer retalho as Input and minizona13 as Difference
iv) use Check Geometry Validity to verify that there an error on the created layer
The difference that I get goes attached as well under tghe name difff_errada13
#2 Updated by Jos Ferraro about 6 years ago
there may sure be a gap, but is it a valid reason to produce an invalid geometry?
I understand that if I operate on valid geometries the result should be valid no matter what. I don't care if the result has small polygons(I may actually want that) but I would like valid ones.
#4 Updated by Jukka Rahkonen about 6 years ago
This is the faulty geometry as WKT and it is a polygon which has a hole outside the shell. It should be either two distinct polygons or a multipolygon with two parts. JTS, GEOS, and QGIS itself is reporting it as invalid. It is also hard to correct by digitizing because the hole should be converted into another polygon feature.
#8 Updated by Giovanni Manghi over 2 years ago
- Resolution set to end of life
- Status changed from Reopened to Closed
End of life notice: QGIS 2.18 LTR