Salvatore Larosa <lrssvtml@...> writes:
> > please, if it is not a sensitive data would be useful if you could > share a sample of the dataset. > my guessing here is that you should run the make valid script (lwgeom > algotithm by processing plugin) before. Hi, Such data are easy to acquire because OpenStreetMap has loads of three-point (A-B-A) polygons. I have been trying to create such artificially sometimes because they make trouble with most other software despite Mapnik but I haven't been successful yet. It is impossible to digitize a three point polygon with QGIS or OpenJUMP, and SQL that should yield A-B-A polygon leads to "NULL" in Spatialite and to an error with PostGIS. select geomfromtext('POLYGON ((0 0,1 1,0 0))'); -Jukka Rahkonen- _______________________________________________ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user