Hello! I need to union a set of the polygons. But I need to save an all holes in the union. CascadePolygonUnion remove all holes in the result. How to do that ? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.osgeo.org/pipermail/geos-devel/attachments/20170228/f29564b3/attachment.html>