Intermaphics.
Thanks,
marian
-Original Message-
From: Nyall Dawson
Sent: Tuesday, June 16, 2020 6:21 PM
To: Richard Duivenvoorde
Cc: Tudorache, Marian ; qgis-user@lists.osgeo.org
Subject: [EXT] Re: [Qgis-user] How to determine the inner surface on a sphere
or ellipsoid
On Wed, 17 Jun 2020 at
On Wed, 17 Jun 2020 at 20:27, Nicolas Cadieux
wrote:
>
> Hi Nyall,
>
> Just out of curiosity, would a very large polygon slow down a spatial query
> or would just a complex one?
That's an open question. It depends on lots of different factors,
including crucially what you're comparing the large
Hi Nyall,
Just out of curiosity, would a very large polygon slow down a spatial query or
would just a complex one? My testing with using shapefiles to reclassify LiDAR
data did show that things could be sped up by splitting large polygons with a
smaller grid but I had attributed this to the com
On Wed, 17 Jun 2020 at 02:10, Richard Duivenvoorde wrote:
>
> On 6/16/20 4:17 PM, Tudorache, Marian wrote:
> > Hi everyone,
> >
> > I have a list of polygons given by a list of points.
> > The polygons are properly drawn on QGIS canvas by creating the geometries,
> > the each geometry is used to
On 6/16/20 6:29 PM, Tudorache, Marian wrote:
> This might help, however I forgot to mention that I am using QGIS 2.18.
> The QgsGeometry Class that you sent me is for QGIS 3.
>
> Do you know something similar on QGIS 2.18?
Hi Marian,
Not that I could quickly find.
But please, please upgrade to
, Marian ; qgis-user@lists.osgeo.org
Subject: [EXT] Re: [Qgis-user] How to determine the inner surface on a sphere
or ellipsoid
On 6/16/20 4:17 PM, Tudorache, Marian wrote:
> Hi everyone,
>
> I have a list of polygons given by a list of points.
> The polygons are properly drawn on QG
On 6/16/20 4:17 PM, Tudorache, Marian wrote:
> Hi everyone,
>
> I have a list of polygons given by a list of points.
> The polygons are properly drawn on QGIS canvas by creating the geometries,
> the each geometry is used to create a Qgsfeature which are saved on a
> shapefile.
> The problem app
Hi,
To my knowledge no. The second option would be a polygone that covers the
earth but that has a hole in it. That is the Generally accepted topology in
GIS.
Nicolas Cadieux
Ça va bien aller!
> Le 16 juin 2020 à 10:28, Tudorache, Marian a
> écrit :
>
> Hi everyone,
>
> I have a list
Hi everyone,
I have a list of polygons given by a list of points.
The polygons are properly drawn on QGIS canvas by creating the geometries, the
each geometry is used to create a Qgsfeature which are saved on a shapefile.
The problem appears in detecting if a point on the Earth is inside or outsi
