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Re: [udig-devel] WMS CRS not properly read 
Hi,
This is pretty unusual, I'm looking at the WKT used by udig for 3003 and it looks the same at a glance. How are you checking to see the projection that uDig is assigning to the layer? There are two ways:
1. Right-click on the layer and select Properties. Then on the properties dialog select Projection. The selected projection should be the one that uDig is using... Hopefully it is 3003 if not then choose 3003 and see if it helps 2. Right-click on the resource in the catalog and select Operations- >Resource Summary. There should be a line that says the projection.
One thing to keep in mind is that currently the default projection of all maps is 4326. So uDig has to reproject the layer from 3003 to 4326. This would cause some distortion. One thing you can do is go into the Window->Preferences Menu item. Select the Project->Map item. In the right there is a Field "EPSG Code of default CRS). Enter -1 there. When you do this the projection of the map will be set to be the same as the first layer added.
One warning about the last point. This is not default behaviour because right now it can cause performance problems with Geoserver if a Shapefile is added as the first layer and a WMS layer *FROM GEOSERVER* is added second.
You can enter 3003 to be the default if you want that to be your default projection as well. 

Hope this helps,

Jesse


On Apr 5, 2007, at 10:02 AM, Fabio Da Soghe wrote:


Hello.

I'm using uDig 1.1.0 RC9 on Windows (XP).
I open a WMS layer (published by Geoserver 1.5.0 RC2a) and it gets badly displayed in uDig's map (the image is distorted). The same layer gets correctly displayed from Geoserver (I've tested it with the builtin Geoserver's Mapbuilder client).
After some (much!) investigation, I've discovered that uDig thinks the layer is in EPSG:4326 (WGS84), but Geoserver correctly advertises it having a CRS EPSG:3003: infact the WMS Capabilities document has this xml fragment: 

      <Layer queryable="0">
        <Name>sprg:tavola_2</Name>
<Title>tavola_2 is a Tagged Image File Format with Geographic information</Title> 
        <Abstract>Generated from tavola_2</Abstract>
        <KeywordList>
          <Keyword>WCS</Keyword>
          <Keyword>tavola_2</Keyword>
          <Keyword>tavola_2</Keyword>
        </KeywordList>
        <!--WKT definition of this CRS:
PROJCS["Monte Mario / Italy zone 1",
  GEOGCS["Monte Mario",
    DATUM["Monte Mario",
SPHEROID["International 1924", 6378388.0, 297.0, AUTHORITY ["EPSG","7022"]], TOWGS84[-50.2, -50.4, 84.8, -0.69, -2.012, 0.459, -5.791915759418465], 
      AUTHORITY["EPSG","6265"]],
    PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]],
    UNIT["degree", 0.017453292519943295],
    AXIS["Geodetic longitude", EAST],
    AXIS["Geodetic latitude", NORTH],
    AUTHORITY["EPSG","4265"]],
  PROJECTION["Transverse_Mercator"],
  PARAMETER["central_meridian", 9.0],
  PARAMETER["latitude_of_origin", 0.0],
  PARAMETER["scale_factor", 0.9996],
  PARAMETER["false_easting", 1500000.0],
  PARAMETER["false_northing", 0.0],
  UNIT["m", 1.0],
  AXIS["Easting", EAST],
  AXIS["Northing", NORTH],
  AUTHORITY["EPSG","3003"]]-->
        <SRS>EPSG:3003</SRS>
<LatLonBoundingBox minx="7.713890299460821" miny="45.10998810306968" maxx="7.833371499203417" maxy="45.176887702656046"/> <BoundingBox SRS="EPSG:3003" minx="1398951.6468292715" miny="4995997.122649521" maxx="1408236.8944173127" maxy="5003290.095381425"/>
As you can argue, this layer is from a Geoserver coverage (a geotiff raster). The very same happens with a vector layer. 

It seems to me what's is going on is:

1) the layer is in EPSG:3003 on the server;
2) it's correctly described in the WMS Capabilities document;
3) uDig thinks it's in EPSG:4326 (why?), so it generates WMS requests with parameter SRS=EPSG:4326 (I verified this on uDig's log); 4) Geoserver receives a request in 4326, has the layer in 3003 so reprojects the raster (here it gets a bit ruined); 5) if I (as I have to) change the CRS of the map in uDig to 3003, uDig reprojects again the image, so it ends up much ruined.
Am I missing something? And, more important, is there a way to workaround this? 

Thanks for any help.

Best Regards,

Fabio Da Soghe

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