Clean invalid vector geometries with QGIS and the LWGEOM library

In QGIS 2.x you can now clean your vector geometries using a tool (for the Proxessing toolbox) that make use of the LWGEOM library, the one used by the PostGIS ST_MakeValid tool, see http://postgis.org/docs/ST_MakeValid.html In QGIS follow this steps: *) install the lwgeom library with the osgeo4w installer *) install the "Processing LWGEOM Provider" plugin *) configure the Processing toolbox with the path to the LWGEOM library