On 01/02/2012 07:36 PM, maning sambale wrote: > We have a nifty convex hull in ftools/vector plugin. I'm looking for > ways to create concave hulls. I have a set of csv points as a source > to generate the polygon. This is updated regularly by non-geo field > workers. Any workaround to generate concave hull in QGIS? > > Mappy new year to all! > > PS. I've seen old discussions in the qgis-dev list.
They can be done in R, and therefore done using ManageR QGIS plugin. The R package is alphahull Though you might want to look at other methods depending on what your actual goal. I messed around with them in regards to territories from GPS telemetry and I believe Anne Ghisla has a whole thesis on the topic. In the end a professor of mine came up with using a density function as the fastest method to get good results. I can find the R code if it will help you. Thanks, Alex _______________________________________________ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user
