On Wed, 2 Oct 2019 at 01:30, C Hamilton <adenacult...@gmail.com> wrote: > > I am guessing this is working on Cartesian coordinates and not geodesic which > is fine if you have a local projection. I think I will go ahead and implement > some similar geodesic algorithms. Thank you for the GRASS link. It will help.
Hi Calvin, I think there's a strong use case for adding this to the c++ API. Would you be willing to put together a proof of concept in Python code and I'll port it to c++ for you? Nyall > > Thanks, > > Calvin > > On Tue, Oct 1, 2019 at 7:45 AM Áron Gergely <aron.gerg...@rasterra.nl> wrote: >> >> Hi Calvin and list, >> >> Have you looked at the GRASS GIS v.generalize tool? >> https://grass.osgeo.org/grass64/manuals/v.generalize.html >> >> The Douglas-Peucker algorithm is implemented there and I have used that with >> (topologic)success recently on many touching polygons. Should work for >> polylines too! >> >> Best regards, >> Aron >> >> On 01/10/2019 08:19, Tim Sutton wrote: >> >> Hi >> >> On 26 Sep 2019, at 17:13, C Hamilton <adenacult...@gmail.com> wrote: >> >> Are there any geodesic QGIS algorithms that simplify lines? "Simplify" just >> uses the projection units of measure. If there isn't I thought I would add >> this to the Shape Tools plugin. I could easily implement the Douglas-Peucker >> algorithm using geodesic math. >> >> For GPS tracks I also see a need to throw out all points that are less than >> a certain distance or less than a certain time interval. I don't see any >> simplification algorithms that make use of time. Am I just missing them? >> >> >> No I don’t think we have any time based simplifiers - would be a great >> addition! >> >> Regards >> >> Tim >> >> >> >> >> Thanks, >> >> Calvin >> _______________________________________________ >> QGIS-Developer mailing list >> qgis-develo...@lists.osgeo.org >> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer >> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer >> >> >> — >> >> >> >> >> >> >> >> >> Tim Sutton >> >> Co-founder: Kartoza >> Ex Project chair: QGIS.org >> >> Visit http://kartoza.com to find out about open source: >> >> Desktop GIS programming services >> Geospatial web development >> GIS Training >> Consulting Services >> >> Skype: timlinux >> IRC: timlinux on #qgis at freenode.net >> >> I'd love to connect. Here's my calendar link to make finding time easy. >> >> >> _______________________________________________ >> QGIS-Developer mailing list >> qgis-develo...@lists.osgeo.org >> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer >> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer > > _______________________________________________ > QGIS-Developer mailing list > qgis-develo...@lists.osgeo.org > List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer > Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer _______________________________________________ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
