QGIS » QGIS Application

Hello everyone,

This is a serious bug and it's causing a lot of trouble for us.

We are using Quantum GIS 2.0 in cartography production, specifically land-use digitizing.

We are using the "avoid intersection" option on Quantum GIS, but in some special weird cases, the tool generates a sliver polygon between two other features that were built using the same process (digitizing with "avoid intersection").

In the attachment there is a shapefile which you can see the error. All features were digitized using "avoid intersection" options. When you run a topology checker validation, it correctly shows an error on a sliver created between two other polygons.

We already investigated the order or digitalization (cw or ccw), but that did not give definitive results. We also tried making sure all polygons the intersection happened to have vertices (to be ignored, for sure) and without vertices.

This is hurting us bad. We have 10 GIS Analysts working full-time with Quantum mapping around 1000km2 and we cannot have topological errors like this. It looks like to me that the problem is with the digitizing tool or some underlying library code, as I've looked up on some other posts.

The links are:

#4880

http://osgeo-org.1560.x6.nabble.com/Polygon-digitalization-td5040680.html