[MapServer-users] WMS with a GPKG-based layer : different responses, dependending on version (1.1.1 vs 1.3.0)

Wed Feb 18 23:47:51 PST 2026

Hi Jukka,

The  https://pasteboard.co
<https://pasteboard.co/XzpHSJjSTiQV.png.Labels> server
was down yesterday. It's up again this morning :-)
You can see the "WMS V1.3.0" is not readable.

I also noticed there was no problem with  demo.mapserver.org WMS examples.
I believe these links are "vector based", just like this one :
https://demo.mapserver.org/cgi-bin/umn?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&BBOX=44.97440639080338087,-93.19614722958594655,44.9933979530691488,-93.16564743649665559&CRS=EPSG:4326&WIDTH=1023&HEIGHT=637&LAYERS=osm-mn&STYLES=&FORMAT=image/png&DPI=96&MAP_RESOLUTION=96&FORMAT_OPTIONS=dpi:96&TRANSPARENT=TRUE

I really wonder what parameters (or lack of) may change responses between
WMS responses.

Sincerely
Philippe

On Wed, Feb 18, 2026 at 2:30 PM Rahkonen Jukka <
jukka.rahkonen at maanmittauslaitos.fi> wrote:

> Hi,
>
> I could not access your sample images.
> I do not know if demo.mapserver.org is GPKG based, but I do not see any
> difference between these two outputs:
>
>
> https://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&VERSION=1.1.0&REQUEST=GetMap&BBOX=4.735,33.118,8.641,38.769&SRS=EPSG%3A4326&WIDTH=490&HEIGHT=709&LAYERS=cities&STYLES=&FORMAT=image%2Fpng&DPI=144&MAP_RESOLUTION=144&FORMAT_OPTIONS=dpi%3A144&TRANSPARENT=TRUE
>
>
> https://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&BBOX=33.118,4.735,38.769,8.641&CRS=EPSG%3A4326&WIDTH=490&HEIGHT=709&LAYERS=cities&STYLES=&FORMAT=image%2Fpng&DPI=144&MAP_RESOLUTION=144&FORMAT_OPTIONS=dpi%3A144&TRANSPARENT=TRUE
>
> -Jukka Rahkonen-
>
> ________________________________________
> Lähettäjä: MapServer-users <mapserver-users-bounces at lists.osgeo.org>
> käyttäjän Philippe Ghesquiere via MapServer-users <
> mapserver-users at lists.osgeo.org> puolesta
> Lähetetty: Keskiviikko 18. helmikuuta 2026 11.37
> Vastaanottaja: MapServer Users <mapserver-users at lists.osgeo.org>
> Aihe: [MapServer-users] WMS with a GPKG-based layer : different responses,
> dependending on version (1.1.1 vs 1.3.0)
>
> Hi all,1) Problem description:Our system is offering an OSM layer, based
> on a WGS84 GPKG (Z=0 to Z=13).I sent two WMS requests, where the only
> difference is the standard version :WMS V1.1.1 request:
> https://xxx/layers/baselayers/wms?service=WMS&version=1.1.1&request=GetMap&Layers=osm_4326&Styles=&SRS=EPSG:4326&Format=image/png&BBOX=45,22.5,67.5,45&Width=1024&Height=1024WMS
> V1.3.0 request:
> https://xxx/layers/baselayers/wms?service=WMS&version=1.3.0&request=GetMap&Layers=osm_4326&Styles=&CRS=EPSG:4326&Format=image/png&BBOX=22.5,45,45,67.5&Width=1024&Height=1024
> I observe some differences :V1.1.1:
> https://pasteboard.co/JjKbU4yvSxrM.png,Labels are easy to read:
> mapcache/mapserver is selecting the right zoom level in the GPKG
> file.V1.3.0: https://pasteboard.co/XzpHSJjSTiQV.png.Labels are much too
> small and not readable. It seems that mapcache/mapserver is selecting a
> higher zoom level than expected and down-sample the image.I do not
> understand why the rendering is not the same.As far as I know, WMS
> requests do not have standard parameters which give a *direct* access to
> zoom layer, resolution or DPI.I tried to add some parameters to my request,
> with no impact on the
> response: DPI=240MAP_RESOLUTION=240FORMAT_OPTIONS=dpi:240.I also tried to
> add parameters in the "MAP block":RESOLUTIONDEFRESOLUTION2) Software
> environment:Mapserver 8.2.0Mapcache 1.14.0Gdal V3.8.4Alma Linux V83) Map
> file excerptMAP    NAME "baselayers_wms"    STATUS ON    SIZE 256 256
> EXTENT -180.0 -90.0 180.0 90.0    UNITS dd#    DEFRESOLUTION 200#
>  RESOLUTION  144    PROJECTION        "init=epsg:4326"    END4) My
> questions:Why do I get different responses between V1.1.1 and V1.3.0 WMS
> requests ?Are there any configuration parameters which have default values
> in one version and not in the other ?I would be glad to have some hints to
> get better WMS 1.3.0 responsesSincerelyPhilippeThe information in this
> e-mail is confidential. The contents may not be disclosed or used by anyone
> other than the addressee. Access to this e-mail by anyone else is
> unauthorised.If you are not the intended recipient, please notify Airbus
> immediately and delete this e-mail.Airbus cannot accept any responsibility
> for the accuracy or completeness of this e-mail as it has been sent over
> public networks. If you have any concerns over the content of this message
> or its Accuracy or Integrity, please contact Airbus immediately.All
> outgoing e-mails from Airbus are checked using regularly updated virus
> scanning software but you should take whatever measures you deem to be
> appropriate to ensure that this message and any attachments are virus free.
The information in this e-mail is confidential. The contents may not be disclosed or used by anyone other than the addressee. Access to this e-mail by anyone else is unauthorised.
If you are not the intended recipient, please notify Airbus immediately and delete this e-mail.
Airbus cannot accept any responsibility for the accuracy or completeness of this e-mail as it has been sent over public networks. If you have any concerns over the content of this message or its Accuracy or Integrity, please contact Airbus immediately.
All outgoing e-mails from Airbus are checked using regularly updated virus scanning software but you should take whatever measures you deem to be appropriate to ensure that this message and any attachments are virus free.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/mapserver-users/attachments/20260219/0d7fb237/attachment-0001.htm>