There's no function for doing that in GEOS. So yes, you will have to implement that yourself, via the approach you suggest.
On Thu, Apr 11, 2019 at 11:57 AM Paul Meems <bontepaar...@gmail.com> wrote: > Hello, > > Currently, I'm working on improving the Shapefile editor of > MapWinGIS/MapWindow5. > Under the hood, it is using a lot of GEOS functions. > > When opening a shapefile we can draw a temporary polygon and use it to > erase a part of the shapefile. We use GEOS::Difference to 'eat' the drawn > polygon from the shapefile. > This works fine. > > We now want a similar option. But this time not 'stamp' the drawn polygon > on the shapefile but remove all vertices of the shapefile that are inside > (under) the drawn polygon. > > Does GEOS have a method for that or should I just loop through all > vertices of the shape and check if it is inside the drawn polygon and > remove it when it does? > > Thanks for any advice, > > Paul > > *Paul Meems * > Release manager, configuration manager > and forum moderator of MapWindow GIS. > www.mapwindow.org > > Owner of MapWindow.nl - Support for > Dutch speaking users. > www.mapwindow.nl > > > *The MapWindow GIS project has a new forum > <https://mapwindow.discourse.group>!* > > > Download the latest MapWinGIS mapping engine. > <https://github.com/MapWindow/MapWinGIS/releases> > > Download the latest MapWindow 5 open source desktop application. > <https://github.com/MapWindow/MapWindow5/releases> > > _______________________________________________ > geos-devel mailing list > geos-devel@lists.osgeo.org > https://lists.osgeo.org/mailman/listinfo/geos-devel
_______________________________________________ geos-devel mailing list geos-devel@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/geos-devel
