[GRASS-user] Wrangling CityGML with GRASS ?

GRASS GRASS user
1

Hi list,

I'm looking for information/howtos/etc. about how to deal with large CityGML data sets using GRASS.

Has anybody already explored this ?

Best,
Peter

<peter.loewe@gmx.de>

2

Hi Peter,

Not personally...
I would guess you would import CityGML through GDAL:
https://3d.bk.tudelft.nl/svitalis/citygml/gdal/2017/07/24/messing-around-with-citygml-on-gdal-2.2.html
There you can create subsets and the like...

What are you planning to do with it, roughly?

Cheers
Stefan

-----Original Message-----
From: grass-user <grass-user-bounces@lists.osgeo.org> On Behalf Of "Peter Löwe"
Sent: torsdag 1. august 2019 11:10
To: grass-user@lists.osgeo.org
Subject: [GRASS-user] Wrangling CityGML with GRASS ?

Hi list,

I'm looking for information/howtos/etc. about how to deal with large CityGML data sets using GRASS.

Has anybody already explored this ?

Best,
Peter

<peter.loewe@gmx.de>

_______________________________________________
grass-user mailing list
grass-user@lists.osgeo.org
https://lists.osgeo.org/mailman/listinfo/grass-user

3

Hi Stefan,

thanks for the link: That's also the latest information we found so far, except for several OSGeo conference recordings (e.g. https://doi.org/10.5446/40913 https://doi.org/10.5446/40694).
My colleagues have ingested CityGML datasets into R, which caused issues with the vector-topology for individual buildings. Also, we have to cope with significant amounts of CityGML datasets, which would require very large amounts of RAM, if the processing is done in R. Since GRASS locations are storage-effective AND GRASS handles vector topologies well, I had hoped that someone already explored this approach further :slight_smile:

If this should be not the case (yet) we'll gladly report at one of next years FOSS4G events.

Best,
peter

<peter.loewe@gmx.de>

Gesendet: Dienstag, 06. August 2019 um 11:13 Uhr
Von: "Stefan Blumentrath" <Stefan.Blumentrath@nina.no>
An: "Peter Löwe" <peter.loewe@gmx.de>, "grass-user@lists.osgeo.org" <grass-user@lists.osgeo.org>
Betreff: RE: [GRASS-user] Wrangling CityGML with GRASS ?

Hi Peter,

Not personally...
I would guess you would import CityGML through GDAL:
https://3d.bk.tudelft.nl/svitalis/citygml/gdal/2017/07/24/messing-around-with-citygml-on-gdal-2.2.html
There you can create subsets and the like...

What are you planning to do with it, roughly?

Cheers
Stefan

-----Original Message-----
From: grass-user <grass-user-bounces@lists.osgeo.org> On Behalf Of "Peter Löwe"
Sent: torsdag 1. august 2019 11:10
To: grass-user@lists.osgeo.org
Subject: [GRASS-user] Wrangling CityGML with GRASS ?

Hi list,

I'm looking for information/howtos/etc. about how to deal with large CityGML data sets using GRASS.

Has anybody already explored this ?

Best,
Peter

<peter.loewe@gmx.de>

_______________________________________________
grass-user mailing list
grass-user@lists.osgeo.org
https://lists.osgeo.org/mailman/listinfo/grass-user

4

Hi Peter,

On Tue, Aug 6, 2019 at 12:23 PM “Peter Löwe” <peter.loewe@gmx.de> wrote:

Hi Stefan,

thanks for the link: That’s also the latest information we found so far, except for several OSGeo conference recordings (e.g. https://doi.org/10.5446/40913 https://doi.org/10.5446/40694).

GML and GMLAS are supported by GDAL 2.2+. However, in order to import GMLAS properly, some tricks are needed (interleaved reading for non-sequential layers, see https://gdal.org/drivers/vector/gmlas.html#performance-issues-with-large-multi-layer-gml-files) which are built into GRASS 7.6+.

My colleagues have ingested CityGML datasets into R, which caused issues with the vector-topology for individual buildings.

That’s not related to the data format, but to the content: 3D polygons. These are not supported in GRASS, when importing you need to convert the data to 2D with v.in.ogr -2, otherwise you get corrupt topology. Maybe this is also needed for R.

Markus M

Also, we have to cope with significant amounts of CityGML datasets, which would require very large amounts of RAM, if the processing is done in R. Since GRASS locations are storage-effective AND GRASS handles vector topologies well, I had hoped that someone already explored this approach further :slight_smile:

If this should be not the case (yet) we’ll gladly report at one of next years FOSS4G events.

Best,
peter

<peter.loewe@gmx.de>

Gesendet: Dienstag, 06. August 2019 um 11:13 Uhr
Von: “Stefan Blumentrath” <Stefan.Blumentrath@nina.no>
An: “Peter Löwe” <peter.loewe@gmx.de>, “grass-user@lists.osgeo.org” <grass-user@lists.osgeo.org>
Betreff: RE: [GRASS-user] Wrangling CityGML with GRASS ?

Hi Peter,

Not personally…
I would guess you would import CityGML through GDAL:
https://3d.bk.tudelft.nl/svitalis/citygml/gdal/2017/07/24/messing-around-with-citygml-on-gdal-2.2.html
There you can create subsets and the like…

What are you planning to do with it, roughly?

Cheers
Stefan

-----Original Message-----
From: grass-user <grass-user-bounces@lists.osgeo.org> On Behalf Of “Peter Löwe”
Sent: torsdag 1. august 2019 11:10
To: grass-user@lists.osgeo.org
Subject: [GRASS-user] Wrangling CityGML with GRASS ?

Hi list,

I’m looking for information/howtos/etc. about how to deal with large CityGML data sets using GRASS.

Has anybody already explored this ?

Best,
Peter

<peter.loewe@gmx.de>

grass-user mailing list
grass-user@lists.osgeo.org
https://lists.osgeo.org/mailman/listinfo/grass-user

grass-user mailing list
grass-user@lists.osgeo.org
https://lists.osgeo.org/mailman/listinfo/grass-user