Re: [QGIS-it-user] Proposta
Totò wrote > Ciao a tuttə > anche secondo me la lista va bene così, senza ulteriori suddivisioni. Penso che sia inutile e controproducente creare liste suddivise per livello di conoscenza di QGIS: così facendo non sarebbe possibile il trasferimento o lo scambio di conoscenze tra chi sa più cose e chi meno o tra chi sa una cosa e chi un'altra e insieme possono poi realizzare qualcosa che non sapeva fare nessuno dei due. Totò wrote > domande senza un inizio e senza > una fine, senza descrivere pienamente il problema o che sistema operativo > utilizzano Noto comunque che avviene anche in questa mailing list, purtroppo, e che anche quando si richiedono chiarimenti per meglio inquadrare il problema e trovare una soluzione, poi l'OP non chiarisce o oppure non aggiorna gli altri utenti sui risultati delle soluzioni proposte. A presto. Andrea -- Sent from: http://osgeo-org.1560.x6.nabble.com/QGIS-Italian-User-f5250612.html ___ QGIS-it-user mailing list QGIS-it-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/qgis-it-user
Re: [Qgis-user] (re)colloring overlapping parts of multipolygons
One idea is that you can use a data defined fill color with an aggregate
expression. Unfortunately this would only work over the entire geometry and
not just a specific section, but combined with opacity, blending modes, or
preprocessing it could possibly be of utility, or at least some interest.
Basically my suggestion would be to use an expression like
color_hsv(aggregate(@layer,aggregate:='count',expression:="id",filter:=intersects($geometry,geometry(@parent)))*40,100,100)
This would give you different colors for each feature based on how many
intersections it has, making the overlapping sections more easily
differentiated. The hue needs to be within a range of 360 though, so using
*40 would have a maximum expected number of 9 intersections and will create
a maximum color difference. Using a smaller multiplier will make colour
changes more subtle.
I don't think splitting/ cracking features in the geometry generator will
be possible (I think the union is a typical set union), but it might be a
handy concept for styling a processed output, so I figured I'd leave it
here in case its helpful.
On Sat, 19 Jun 2021, 22:24 Richard Duivenvoorde,
wrote:
> Thanks all for the tips,
>
> I was indeed hoping I could stick to geometry generation only and then in
> one way or another split up the parts of the multipolygons...
>
> But receiving the actual setup now (see attached), my conclusion is now
> indeed to do some processing steps, either vector or raster based... (
> though doing the geometry generation was fun ;-) )
>
> Again, thanks all for the input!
>
> Richard
>
> On 6/19/21 4:45 PM, Richard Duivenvoorde wrote:
> >
> >
> > Hi List,
> >
> > I'm experimenting to create 'flower'-shaped polygons for a point layer,
> denoting the signal coverage of several directional radio transmitters on a
> pole (fyi: to find/locate bats with small transmitters).
> >
> > After some fiddling I came to the attached result for a point with 3
> (but dynamic from attribute) transmitters using the following expression:
> >
> > collect_geometries(
> > array_foreach( string_to_array("azimuths"),
> > make_circle( make_point(
> > $x + "bereik_m"/2 * cos(radians(@element)),
> > $y + "bereik_m"/2* sin(radians(@element))), "bereik_m" )
> > ))
> >
> > The result being a multipolygon with overlapping parts.
> >
> > In this work the overlapping area'a are (apparently) the most
> interesting, as there the 'location' accuracy is highest.
> >
> > So my question: is there a way to give the overlapping area's really
> different colors.
> > I've been playing with the layer rendering options, but ideally the
> area's in which there is no, 2 parts, 3 parts, and 4 parts overlapping
> should be differently colored..
> >
> > I could try to create more advanced expressions (or probably I would go
> for some python) for that, but I was hoping maybe there is another
> trick/idea to use current multi-polygons, without adding 'parts'
> >
> > Any help/tip is appreciated.
> >
> > Regards & TIA,
> >
> > Richard Duivenvoorde
> >
> >
> > ___
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> >
>
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[Qgis-user] Exporting to UE4
So I just recently started using QGIS for turning .tiff files into a .dem file that can be read through Unreal Engine for height map generating and I have no Idea how to, does anyone know?Sent from my Galaxy___ 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
Re: [Qgis-user] (re)colloring overlapping parts of multipolygons
Thanks all for the tips,
I was indeed hoping I could stick to geometry generation only and then in one
way or another split up the parts of the multipolygons...
But receiving the actual setup now (see attached), my conclusion is now indeed
to do some processing steps, either vector or raster based... ( though doing
the geometry generation was fun ;-) )
Again, thanks all for the input!
Richard
On 6/19/21 4:45 PM, Richard Duivenvoorde wrote:
>
>
> Hi List,
>
> I'm experimenting to create 'flower'-shaped polygons for a point layer,
> denoting the signal coverage of several directional radio transmitters on a
> pole (fyi: to find/locate bats with small transmitters).
>
> After some fiddling I came to the attached result for a point with 3 (but
> dynamic from attribute) transmitters using the following expression:
>
> collect_geometries(
> array_foreach( string_to_array("azimuths"),
> make_circle( make_point(
> $x + "bereik_m"/2 * cos(radians(@element)),
> $y + "bereik_m"/2* sin(radians(@element))), "bereik_m" )
> ))
>
> The result being a multipolygon with overlapping parts.
>
> In this work the overlapping area'a are (apparently) the most interesting, as
> there the 'location' accuracy is highest.
>
> So my question: is there a way to give the overlapping area's really
> different colors.
> I've been playing with the layer rendering options, but ideally the area's in
> which there is no, 2 parts, 3 parts, and 4 parts overlapping should be
> differently colored..
>
> I could try to create more advanced expressions (or probably I would go for
> some python) for that, but I was hoping maybe there is another trick/idea to
> use current multi-polygons, without adding 'parts'
>
> Any help/tip is appreciated.
>
> Regards & TIA,
>
> Richard Duivenvoorde
>
>
> ___
> 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
>
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Re: [QGIS-it-user] Proposta
Ciao a tuttə anche secondo me la lista va bene così, senza ulteriori suddivisioni. Siamo in un periodo storico in cui si ha un estremo bisogno di risposte veloci e la lista non è veloce, quindi si cercano altre vie con Facebook. Facebook perché: 1. tutti lo usano; 2. tutti lo hanno nello smartphone; 3. ogni domande è letta da centinaia di persone e c'è sempre qualcuno disposto a rispondere; 4. tutti ci colleghiamo più volte al giorno; 5. a tutti piace farsi notare Telegram è un po' diverso ma non tanto. Per fortuna non perdiamo nulla, perché secondo me il livello delle domande è cosi basso che è meglio farle su Facebook: domande senza un inizio e senza una fine, senza descrivere pienamente il problema o che sistema operativo utilizzano, secondo me è meglio che restino su facebook. saluti saluti - https://pigrecoinfinito.com/ -- Sent from: http://osgeo-org.1560.x6.nabble.com/QGIS-Italian-User-f5250612.html ___ QGIS-it-user mailing list QGIS-it-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/qgis-it-user
Re: [Qgis-user] (re)colloring overlapping parts of multipolygons
I second Nicolas' IDW suggestion though since a point source signal
strength is proportional to the inverse square distance you might want to
take that into account
On Sat, Jun 19, 2021, 10:57 Nicolas Cadieux
wrote:
> Hi,
> There are multiple ways of doing this. The Join attributes by location
> (Summary) could help you could the number of polygons overlapping the
> point. You could then split the overlapping circles into smaller parts
> and then use the join by location again to transfer the sums polygon of the
> points back to the various circle parts. Then use the symbology by
> classification using this field.
>
> A much better way would be to make an interpolation of your point data
> instead. The easy way would be just to make a heat map. The best way would
> probably be to use IDW with a search radius. The gdal version of idw found
> in processing will permit you to do this. Find an interpolation method
> that is compatible with the phenomenon you are studying. For example IDW
> is would be better that a tin or a voronoï polygon.
>
> Nicolas Cadieux
> https://gitlab.com/njacadieux
>
> Le 19 juin 2021 à 10:54, Richard Duivenvoorde a
> écrit :
>
>
>
> Hi List,
>
> I'm experimenting to create 'flower'-shaped polygons for a point layer,
> denoting the signal coverage of several directional radio transmitters on a
> pole (fyi: to find/locate bats with small transmitters).
>
> After some fiddling I came to the attached result for a point with 3 (but
> dynamic from attribute) transmitters using the following expression:
>
> collect_geometries(
> array_foreach( string_to_array("azimuths"),
> make_circle( make_point(
>$x + "bereik_m"/2 * cos(radians(@element)),
>$y + "bereik_m"/2* sin(radians(@element))), "bereik_m" )
>))
>
> The result being a multipolygon with overlapping parts.
>
> In this work the overlapping area'a are (apparently) the most interesting,
> as there the 'location' accuracy is highest.
>
> So my question: is there a way to give the overlapping area's really
> different colors.
> I've been playing with the layer rendering options, but ideally the area's
> in which there is no, 2 parts, 3 parts, and 4 parts overlapping should be
> differently colored..
>
> I could try to create more advanced expressions (or probably I would go
> for some python) for that, but I was hoping maybe there is another
> trick/idea to use current multi-polygons, without adding 'parts'
>
> Any help/tip is appreciated.
>
> Regards & TIA,
>
> Richard Duivenvoorde
>
> ___
> 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
>
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> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
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Re: [Qgis-user] (re)colloring overlapping parts of multipolygons
Hi,
There are multiple ways of doing this. The Join attributes by location
(Summary) could help you could the number of polygons overlapping the point.
You could then split the overlapping circles into smaller parts and then use
the join by location again to transfer the sums polygon of the points back to
the various circle parts. Then use the symbology by classification using this
field.
A much better way would be to make an interpolation of your point data instead.
The easy way would be just to make a heat map. The best way would probably be
to use IDW with a search radius. The gdal version of idw found in processing
will permit you to do this. Find an interpolation method that is compatible
with the phenomenon you are studying. For example IDW is would be better that
a tin or a voronoï polygon.
Nicolas Cadieux
https://gitlab.com/njacadieux
> Le 19 juin 2021 à 10:54, Richard Duivenvoorde a écrit :
>
>
>
> Hi List,
>
> I'm experimenting to create 'flower'-shaped polygons for a point layer,
> denoting the signal coverage of several directional radio transmitters on a
> pole (fyi: to find/locate bats with small transmitters).
>
> After some fiddling I came to the attached result for a point with 3 (but
> dynamic from attribute) transmitters using the following expression:
>
> collect_geometries(
> array_foreach( string_to_array("azimuths"),
> make_circle( make_point(
>$x + "bereik_m"/2 * cos(radians(@element)),
>$y + "bereik_m"/2* sin(radians(@element))), "bereik_m" )
>))
>
> The result being a multipolygon with overlapping parts.
>
> In this work the overlapping area'a are (apparently) the most interesting, as
> there the 'location' accuracy is highest.
>
> So my question: is there a way to give the overlapping area's really
> different colors.
> I've been playing with the layer rendering options, but ideally the area's in
> which there is no, 2 parts, 3 parts, and 4 parts overlapping should be
> differently colored..
>
> I could try to create more advanced expressions (or probably I would go for
> some python) for that, but I was hoping maybe there is another trick/idea to
> use current multi-polygons, without adding 'parts'
>
> Any help/tip is appreciated.
>
> Regards & TIA,
>
> Richard Duivenvoorde
>
> ___
> 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
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Re: [Qgis-user] (re)colloring overlapping parts of multipolygons
Hi Richard,
Are you looking for something on the fly? Or you can run some analysis?
Alex
A sábado, 19/06/2021, 15:54, Richard Duivenvoorde
escreveu:
>
>
> Hi List,
>
> I'm experimenting to create 'flower'-shaped polygons for a point layer,
> denoting the signal coverage of several directional radio transmitters on a
> pole (fyi: to find/locate bats with small transmitters).
>
> After some fiddling I came to the attached result for a point with 3 (but
> dynamic from attribute) transmitters using the following expression:
>
> collect_geometries(
> array_foreach( string_to_array("azimuths"),
> make_circle( make_point(
> $x + "bereik_m"/2 * cos(radians(@element)),
> $y + "bereik_m"/2* sin(radians(@element))), "bereik_m" )
> ))
>
> The result being a multipolygon with overlapping parts.
>
> In this work the overlapping area'a are (apparently) the most interesting,
> as there the 'location' accuracy is highest.
>
> So my question: is there a way to give the overlapping area's really
> different colors.
> I've been playing with the layer rendering options, but ideally the area's
> in which there is no, 2 parts, 3 parts, and 4 parts overlapping should be
> differently colored..
>
> I could try to create more advanced expressions (or probably I would go
> for some python) for that, but I was hoping maybe there is another
> trick/idea to use current multi-polygons, without adding 'parts'
>
> Any help/tip is appreciated.
>
> Regards & TIA,
>
> Richard Duivenvoorde
> ___
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> List info: https://lists.osgeo.org/mailman/listinfo/qgis-user
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
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Re: [Qgis-user] Shifting polygon boundaries
On 6/18/2021 4:44 PM, Charles Dixon-Paver wrote: If you have already digitized the new boundary as a line feature you can use processing tools to split the boundary areas with the line features, but you will still have to merge in an edit session with the digitizing tools. I think you could just dissolve the two polygons without resorting to an edit session. ___ 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
[Qgis-user] (re)colloring overlapping parts of multipolygons
Hi List,
I'm experimenting to create 'flower'-shaped polygons for a point layer,
denoting the signal coverage of several directional radio transmitters on a
pole (fyi: to find/locate bats with small transmitters).
After some fiddling I came to the attached result for a point with 3 (but
dynamic from attribute) transmitters using the following expression:
collect_geometries(
array_foreach( string_to_array("azimuths"),
make_circle( make_point(
$x + "bereik_m"/2 * cos(radians(@element)),
$y + "bereik_m"/2* sin(radians(@element))), "bereik_m" )
))
The result being a multipolygon with overlapping parts.
In this work the overlapping area'a are (apparently) the most interesting, as
there the 'location' accuracy is highest.
So my question: is there a way to give the overlapping area's really different
colors.
I've been playing with the layer rendering options, but ideally the area's in
which there is no, 2 parts, 3 parts, and 4 parts overlapping should be
differently colored..
I could try to create more advanced expressions (or probably I would go for
some python) for that, but I was hoping maybe there is another trick/idea to
use current multi-polygons, without adding 'parts'
Any help/tip is appreciated.
Regards & TIA,
Richard Duivenvoorde
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