[QGIS-Developer] Tool to create Mesh from raster layer?

[Saber Razmjooei]

Hi Andreas,

Indeed, there is no native tool at the moment to convert raster directly to
mesh. I filed a ticket with a link to this discussion so we can add it to
QGIS later:
https://github.com/qgis/QGIS/issues/52313

But, in general, I would first try to find the source of the DEM raster
(e.g. point cloud or spot survey) and use the raw data to create the mesh.
This will avoid double interpolation :)

Kind regards
Saber


On Mon, 20 Mar 2023 at 14:31, Andreas Neumann via QGIS-Developer <
qgis-developer at lists.osgeo.org> wrote:

> and there seems to be https://github.com/heremaps/tin-terrain
>
> However, I am looking for a solution integrated in QGIS ...
>
> On 2023-03-20 14:28, Andreas Neumann via QGIS-Developer wrote:
>
> Hi,
>
> Yes - exporting the raster to xyz points or to contour lines are both
> workarounds.
>
> It would be nice, if QGIS would gain a direct algorithm of creating a mesh
> from a DEM - as many DTMs are provided as raster. It seems like SAGA has a
> raster DTM to TIN algorithm (
> https://saga-gis.sourceforge.io/saga_tool_doc/8.5.1/tin_tools_0.html ) -
> but SAGA is a bit complicated to use within QGIS and SAGA support within
> QGIS processing may disappear in the future. Perhaps we could port the SAGA
> algorithm to QGIS - or maybe an alternative algorithm?
>
> My goal is to replace the raster DTM with a MESH for 3D display - with the
> ability to edit the MESH at important points. The builtin triangulation of
> the QGIS 3D viewer (where you can have a raster DTM as a terrain source) is
> sometimes doing weird things - I'd like to control that better - e.g. by
> introducing additional break lines or manually editing the Mesh.
>
> Andreas
>
> On 2023-03-20 14:20, Stefan Giese (WhereGroup) via QGIS-Developer wrote:
>
> Hi all,
>
> I think it is not nessasary to go through Blender, just use theese two
> algorithm:
>
>    - pixeltopoints
>    - tinmeshcreation
>
> Best regards
>
> Stefan
> Am 20.03.2023 um 14:11 schrieb Sebastian Gutwein via QGIS-Developer:
>
> The ridiculous work around I use is to go through Blender using the
> BlenderGIS plugin. Import the raster into Blender as a new mesh > Decimate
> the mesh > Export as a shapefile > Run TIN Mesh Creation in QGIS.
>
>
> On Mon, Mar 20, 2023 at 9:03 AM Saber Razmjooei via QGIS-Developer <
> qgis-developer at lists.osgeo.org> wrote:
>
> Hi Andreas,
>
> There should be a tool to convert vector to mesh (under Processing > Mesh
> > TIN Mesh Creation). There will also be some new Processing tools for
> handling point clouds. But I am not aware of any Raster > Mesh tools.
>
> Kind regards
> Saber
>
> On Mon, 20 Mar 2023 at 13:56, Andreas Neumann via QGIS-Developer <
> qgis-developer at lists.osgeo.org> wrote:
>
> Hi QGIS devs,
>
> Is there a tool available to create a Mesh (or TIN as a special mesh
> variation) from a source raster layer containing terrain values?
>
> I did not find one - but maybe I didn't look everywhere.
>
> If not in QGIS - do you know an external Open Source tool that could do
> that, while keeping real world coordinates?
>
> Thanks,
>
> Andreas
> _______________________________________________
> QGIS-Developer mailing list
> QGIS-Developer at lists.osgeo.org
> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>
>
>
> --
> Saber Razmjooei
> www.lutraconsulting.co.uk
> +44 (0)7568 129733
> _______________________________________________
> QGIS-Developer mailing list
> QGIS-Developer at lists.osgeo.org
> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>
>
>
> --
> ___________________________
> Sebastian "Bas* " Gutwein
> *rhymes with Josh
>
> Regenerative Design Group
> 1 Chevalier Ave
> Greenfield, Ma 01301
> Web: regenerativedesigngroup.com
> (631) 241-1018
>
> *Look close, think big, make change. *
>
>
> _______________________________________________
> QGIS-Developer mailing listQGIS-Developer at lists.osgeo.org
> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>
> --
> Mit freundlichen Grüßen
> Stefan Giese
> Projektleiter/Consultant
> **********************************************
> FOSSGIS Konferenz
> 15.-18. März 2023 in Berlinhttps://fossgis-konferenz.de/2023/
>
> WhereGroup-Beiträge auf der FOSSGIShttps://wheregroup.com/unternehmen/aktuelles/
> **********************************************
> WhereGroup GmbH
> Schwimmbadstr. 2
> 79100 Freiburg
> Germany
>
> Tel.: +49 (0)761 / 519 102 - 61
> Fax: +49 (0)761 / 519 102 - 11
> stefan.giese at wheregroup.comwww.wheregroup.com
> Geschäftsführer:
> Olaf Knopp, Peter Stamm
> Amtsgericht Bonn, HRB 9885
>
>
> _______________________________________________
> QGIS-Developer mailing list
> QGIS-Developer at 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-Developer at 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-Developer at lists.osgeo.org
> List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
>


-- 
Saber Razmjooei
www.lutraconsulting.co.uk
+44 (0)7568 129733
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-developer/attachments/20230321/6cb5010e/attachment-0001.htm>