Indeed, we eventually figured out that WMS getInfo is considered a check
in the center of a single pixel.
Thinking,
Richard for a while we forced the renderers to leave us a hook so we
could make our info request, is there any way we can ask the WMS
renderers to leave some hints on the layer blackboard about the image
rendered? The same plugin making the rendering contribution can provide
the hint ...
Jody
Hi Jody,
the projections I am trying are both supported by the WMS.
Unfortunately I have no Java hosting, but it's a simple shapefile
which can be set up with Geoserver. I am using 1.4.
The shapefile can be found here (200 Kb, native projection EPSG:28992,
uDIG set to RD / New projection):
http://www.osgis.nl/lausanne/nl-prov.zip
An example request which uDIG is fyring off is (this request is really
strange since the BBOX is not the BBOX of the map image shown anymore!
and X and Y are always 1):
/geoserver/wms?Y=1&X=1&SERVICE=WMS&INFO_FORMAT=text/html&LAYERS=ogctestbed:nl-prov&FORMAT=image/png&HEIGHT=3&REQUEST=GetFeatureInfo&WIDTH=3&BBOX=188907.50415179788,391802.21024004533,192453.4125990071,395348.1186872545&SRS=EPSG:28992&QUERY_LAYERS=ogctestbed%3Anl-prov&VERSION=1.1.1
HTTP/1.1" 200 447
Thanks in advance.
Best regards,
Bart
Jody Garnett schreef:
Good question, it makes a direct call when able to make a direct
rendering of the WMS image (ie udig is using a coordinate system
supported by the WMS). In rare cases it may have to resample the
image onto the screen (making up for lack of WMS projections), we
could check that we back project the query into the coordinate space
of the original image... but as I recall I wrote this one and went to
some trouble to get it right.
Can you point us at a service illustrating the problem, perhaps in a
jira report.
Jody
Hi list,
how accurate is uDIG with respect to GetFeatureInfo?
I have tried it against 2 WMS's, Geoserver and Deegree, and at the
borders of provinces, a lot of times the wrong element is returned.
Ofcourse this could also be due to the WMS's.
So I checked Gaia, and using Gaia it is very accurate for Geoserver,
so I am assuming it is a uDIG problem.
Any input appreciated.
Best regards,
Bart
_______________________________________________
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
