[MapServer-users] UVRASTER reprojection

[Alistair Everett]

Hi all,

I'm trying to use the UVRASTER connection to plot wind barbs. I noticed if
I request the layer in a different projection the location of the arrows
are reprojected but the angle, and presumably vector components, are not -
rather they remain in the same direction relative to my screen. It's a
little unclear from the documentation if this is the expected behaviour for
UVRASTER or not? I included a pasteboard link to a screenshot to show what
I mean, compare for example vectors in the corners of the data and you will
see they point in the same direction relative to my screen, rather than
being rotated to match the projection.

If this is expected, does anyone have any suggested ways of working around
this?

If this is not expected, does anyone have any ideas what I've done wrong? I
can provide some sample data if someone wants to try to reproduce.

I'm using: MapServer version 8.4.0 PROJ version 9.4 GDAL version 3.11
OUTPUT=PNG OUTPUT=JPEG SUPPORTS=PROJ SUPPORTS=AGG SUPPORTS=FREETYPE
SUPPORTS=CAIRO SUPPORTS=ICONV SUPPORTS=FRIBIDI SUPPORTS=WMS_SERVER
SUPPORTS=WMS_CLIENT SUPPORTS=WFS_SERVER SUPPORTS=WFS_CLIENT
SUPPORTS=WCS_SERVER SUPPORTS=SOS_SERVER SUPPORTS=OGCAPI_SERVER
SUPPORTS=FASTCGI SUPPORTS=THREADS SUPPORTS=GEOS SUPPORTS=PBF INPUT=JPEG
INPUT=OGR INPUT=GDAL INPUT=SHAPEFILE INPUT=FLATGEOBUF

Screenshot: https://pasteboard.co/WTgbexDmQaAe.png

Example mapfile: https://pastebin.com/ibPc6gVK

Thanks,
Alistair

-----------------------------
Dr Alistair Everett
Senioringeniør / Senior Software Engineer
Avdeling for Geoutvikling

Phone: +47 939 68 985
Email: alistair.everett at met.no

Meteorologisk Institutt,
Henrik Mohns plass 1,
0313 Oslo
-----------------------------
*Dr Alistair Everett*
Senioringeniør / Senior Software Engineer
Avdeling for Geoutvikling

*Phone:* +47 939 68 985
*Email:* alistair.everett at met.no <alistaire at met.no>

*Meteorologisk Institutt*,
Henrik Mohns plass 1,
0313 Oslo
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