[mapguide-users] metadata in a layer for wms-service

Tue Sep 19 14:16:11 EDT 2006

Hi Axel,

Thank you for sending me your data. I believe the problem stems from the definition you are using for EPSG:31467 in your config file:

<translate from="EPSG:31467">GEOGCS["DHDN", DATUM["Deutsches Hauptdreiecksnetz", SPHEROID["Bessel 1841", 6377397.155, 299.1528128, AUTHORITY["EPSG","7004"]], TOWGS84[598.1, 73.7, 418.2, 0.202, 0.045, -2.455, 6.7], AUTHORITY["EPSG","6314"]], PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]], UNIT["degree of angle",0.017453292519943295], AXIS["Geodetic latitude",NORTH], AXIS["Geodetic longitude",EAST], AUTHORITY["EPSG","4314"]], PROJECTION["Transverse_Mercator"], PARAMETER["semi_major", 6377397.155], PARAMETER["semi_minor", 6356078.962818189], PARAMETER["central_meridian", 9.0], PARAMETER["latitude_of_origin", 0.0], PARAMETER["scale_factor", 1.0], PARAMETER["false_easting", 3500000.0], PARAMETER["false_northing", 0.0], UNIT["metre",1.0], AXIS["Northing",NORTH], AXIS["Easting",EAST], AUTHORITY["EPSG","31467"]] </translate>

When I debugged into the code, the meters-per-unit value calculated for this coordinate system came out to be a very large value, and this in turn caused the map to be requested at a minute scale (close to 1:300000000). That is why nothing showed up.

I used the html test pages (http://localhost/mapguide/mapagent/index.html) to call GetSpatialContexts (under the Feature Service API grouping) for the feature source I created from your data using the DHDN.Gauss3d-3 coordinate system. This gave me the actual WKT string used for this feature source. If I substitute that into the EPSG:31467 definition, as below, I can successfully retrieve a map image :-)

<translate from="EPSG:31467">PROJCS["DHDN.Gauss3d-3",GEOGCS["DHDN.LL",DATUM["DHDN",SPHEROID["BESSEL",6377397.155,299.15281535],TOWGS84[582.0000,105.0000,414.0000,-1.040000,-0.350000,3.080000,8.30000000]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]],PROJECTION["Transverse_Mercator"],PARAMETER["false_easting",3500000.000],PARAMETER["false_northing",0.000],PARAMETER["scale_factor",1.000000000000],PARAMETER["central_meridian",9.00000000000000],PARAMETER["latitude_of_origin",0.00000000000000],UNIT["Meter",1.00000000000000]] </translate>

This is the URL I used for the WMS GetMap request:

http://localhost/mapguide/mapagent/mapagent.fcgi?REQUEST=GetMap&SERVICE=WMS&VERSION=1.1.1&LAYERS=Axel/Layers/Genehmigungsgrenze%202001&BBOX=3556793.54,5374822.7,3557330.2495,5375186.37&CRS=EPSG:31467&WIDTH=600&HEIGHT=400&BGCOLOR=0x0000FF&TRANSPARENT=FALSE&FORMAT=image/PNG

I hope this helps.

Chris.

  _____  

From: Chris Claydon 
Sent: September 18, 2006 12:28 PM
To: 'users at mapguide.osgeo.org'
Subject: RE: [mapguide-users] metadata in a layer for wms-service

Hi Axel,

Would you be able to send me the data you are using for this layer?

I'd like to try to reproduce what you're doing.

Chris.

p.s. One thing you could try, though it is probably not ideal, is to add a mapping for EPSG:4326 to your OgcWmsService.config.awd file as well. That way, if the client does attempt to use EPSG:4326 instead of EPSG:31467, at least you may still get a map image returned.

  _____  

From: Axel Dörr [mailto:a.doerr at doerrib.de] 
Sent: September 17, 2006 4:10 AM
To: users at mapguide.osgeo.org
Subject: [mapguide-users] metadata in a layer for wms-service

Hello list,

once again i need some help to deliver maps via wms .

With the friendly and very useful help of Andy and Bruce i got the right WKT Translation for EPSG:31467.

I added a <translate> command in the OgcWmsService.config.awd  - and i hope found the correct place for it. Have a look at the attachment.

The properties of the layer to publish are populated in "bounds-field" with: <Bounds SRS="EPSG:31467" west="3556600" south="5374600" east="3557700" north="5375600"/>

The field for "extended metadata" in studio for the requested layer is empty. 

The getmap-request looks like this: 

http://localhost/mapguide/mapagent/mapagent.fcgi?REQUEST=GETMAP&SERVICE=WMS&VERSION=1.1.1&STYLE=DEFAULT&FORMAT=image/png&SRS=EPSG:31467&BBOX=3556600,5374600,3557700,5375600&WIDTH=200&HEIGHT=200&LAYERS=Test/Layer/Genehmigungsgrenze%202001

With this i don´t get an error-message anymore, but a map is also not displayed.

Gaia tells me within the Selected Layer Info:

Name:  Test/Layer/Genehmigungsgrenze 2001
Title: TEST WMS
Namespace: 
Keywords: 

LL BBox: (-180,-90;180,90)

BBox: (-180,-90;180,90)
BBox: (3556600,5374600;3557700,5375600)

Supported SRS: 
EPSG:31467
EPSG:4326

The Log of Gaia is the following:

<ServiceExceptionReport version="1.1.1">

 <ServiceException code="InvalidSRS">

  The spatial reference system specified is not supported. (Found SRS=EPSG:4326)

 </ServiceException>

</ServiceExceptionReport>

---------------------------------------
Error during HandlerWMS:AsyncReader
Source URL = http://entwicklung/mapguide/mapagent/mapagent.fcgi?
Layer name = Test/Layer/Genehmigungsgrenze 2001
---------------------------------------
CarbonTools.Core.Base.CarbonToolsException: Server responded with an error

   at CarbonTools.Core.WMS.HandlerWMS.AsyncReader(IAsyncResult result)

Apparently EPSG:4326 wins against EPSG:31467. At least this is my impression.

Regards,

Axel

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