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Re: R: [udig-devel] WMS CRS not properly read

I will publish an SDK right now that has all the Geotools source code so that you can debug this problem. I can't do it without access to your WMS. Put a break point on the Constructor of the WebMapServer class and see what CRS it parses out.

You can also send the entire WMS getCapabalities, maybe that will give me some clues beyond what the fragment says (although the fragment looks ok).

I'll send an email when I get the SDK out.

Jesse


On Apr 6, 2007, at 1:09 AM, Fabio Da Soghe wrote:

Hello Jessie.

Thanks for your replay.

Yes, I agree there's something weird going on.

If I right-click on the resource in the catalog and select Operations -> Resource Summary, it says WGS84 (this was the test I did when I wrote my previous mail).

I checked the layer properties (Right-click on the layer and select Properties). It's WGS84 as well.

I followed your hints. First I set -1 as default map projection (Window->Preferences Menu item -> Project->Map item). That changed nothing: uDig keep using EPSG:4326.

Then I changed the projection used for the layer (Layer- >properties), forcing to be 3003. uDig ignores that! I read from its log (and from Geoserver's log) that WMS requests have always SRS=EPSG:4326.

I'm using the SDK version of 1.1.0 RC9 on windows. Maybe there's something I can check around geotools or something like that?

Thank you again!

Cheers,

Fabio

-----Messaggio originale-----
Da: udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx
[mailto:udig-devel-bounces@xxxxxxxxxxxxxxxxxxxxx] Per conto
di Jesse Eichar
Inviato: giovedì 5 aprile 2007 22.03
A: User-friendly Desktop Internet GIS
Oggetto: 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

_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel

_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel


_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel



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