Helmut Kudrnovsky

IIRC, there was recently a GDAL update in OSGeo4W. Maybe the build environment is not updated yet. @landam

seems to be related: https://lists.osgeo.org/pipermail/grass-user/2023-January/083131.html

anyone a hint how to rebase this PR to main? ;-)

some follow up test with real data of mountain area with high geomorphology variability: https://lists.osgeo.org/pipermail/grass-user/2023-March/083153.html

see also: https://lists.osgeo.org/pipermail/grass-user/2023-March/083154.html

real data example ``` g.region -p projection: 99 (MGI / Austria GK West) zone: 0 datum: hermannskogel ellipsoid: bessel north: 218281.5 south: 204874.5 west: 49389.5 east: 62610.5 nsres: 1 ewres:...

any thoughts?

left `r.sun patched GRASS 8.3.dev`, right `r.sun GRASS 8.2.1 unpatched`  with the patch/PR: not much differences on southern oriented mountain slopes, though steeper northern oriented slopes

tested here with ``` System Info GRASS version: 8.3.2 Code revision: exported Build date: 2024-05-20 Build platform: x86_64-w64-mingw32 GDAL: 3.9.0 PROJ: 9.4.0 GEOS: 3.12.1 SQLite: 3.45.1 Python: 3.12.4 wxPython: 4.2.1...

testing here with ``` System Info GRASS version: 8.3.2 Code revision: exported Build date: 2024-05-20 Build platform: x86_64-w64-mingw32 GDAL: 3.9.0 PROJ: 9.4.0 GEOS: 3.12.1 SQLite: 3.45.1 Python: 3.12.4 wxPython: 4.2.1...