Projections and WMS servers

[Ed McNierney]

Nico -

Yes, that should be expected; the GetCapabilities request returns the server's capabilities, and if you ask it to do something it has told you it cannot do, you should expect it to be unable to do it <g>.  You need to select a projection that that server CAN provide; then, by describing that layer's projection to MapServer with a PROJECTION block (one that describes the projection used, not what you want it to be) you can notify MapServer that the returned data needs to be reprojected (if your map's output projection is different).

        - Ed

Ed McNierney
President and Chief Mapmaker
TopoZone.com / Maps a la carte, Inc.
73 Princeton Street, Suite 305
North Chelmsford, MA  01863
ed at topozone.com
(978) 251-4242

-----Original Message-----
From: UMN MapServer Users List [mailto:MAPSERVER-USERS at LISTS.UMN.EDU] On Behalf Of Nico Alberti
Sent: Tuesday, September 28, 2004 11:31 AM
To: MAPSERVER-USERS at LISTS.UMN.EDU
Subject: Re: [UMN_MAPSERVER-USERS] Projections and WMS servers

On Tue, 28 Sep 2004 11:01:46 -0400, Ed McNierney <ed at topozone.com> wrote:
> Nico -
>
> Can you send the URL of the WMS server you're using?  The only service I can find on that site is a WFS feature service.
>

I used this one. Somehow it displays something, so I hope it is the right service :-) http://mapserv2.esrin.esa.it/cubestor/cubeserv/cubeserv.cgi?

> You need to be able describe the projection of the data coming from the WMS service, and MapServer will request the data in that projection (which must, of course, be a supported projection on that server).
>

And I guess I can know that querying for its capabilities and looking for epsg:26951 in the xml file I receive, can't I? I did not see it, and if I do:

  LAYER
    NAME "Esrin"
    STATUS ON
    TYPE RASTER
    CONNECTIONTYPE WMS
    CONNECTION "http://mapserv2.esrin.esa.it/cubestor/cubeserv/cubeserv.cgi?"
    UNITS METERS
    SIZEUNITS PIXELS
    TOLERANCE 0
    TOLERANCEUNITS PIXELS
    METADATA
      "wms_srs"    "epsg:26951"
      "wms_name"    "WATRCRSL_1M:Foundation:CubeWerx"
      "wms_server_version"    "1.1.1"
      "wms_formatlist"    "image/gif,image/png,image/jpeg,image/wbmp"
      "wms_format"    "image/gif"
    END
    PROJECTION
      "init=epsg:26951"
    END
  END

I get a blank layer (while other ones are correctly displayed)

> You will have two types of PROJECTION blocks in your map file.  You should have one for each LAYER, describing the native projection in which that layer's data is stored.  And you should have one at the top level of your map file, indicating what *output* projection should be used in producing the requested map.
>
> The PROJECTION block below is superficially OK, but it's certainly not
> the Monte Mario

Uh. Yes, you are right. For some reason, I thought using epsg:26951 would not have worked.

Thank you for your help!
--
Ciao
Nico