Hi, the problem I see with your approach is that OpenLayers.Control.GetFeatureInfo creates a GetFeatureInfo request for the map extent, not for a tile. I would recommend sending GetFeatureInfo requests to the underlying WMS, as explained in http://getsatisfaction.com/opengeo/topics/error_in_wmsgetfeatureinfo#reply_2612983
Regards, Andreas. On Jul 27, 2010, at 08:55 , Miles Jordan wrote: > Hi, > > I've been debugging a problem that I've been having with using the > WMSGetFeatureInfo control and GeoWebCache. > > Basically I am setting OpenLayers.DOTS_PER_INCH to 90.71428571428572 which is > what GeoWebCache expects by default, however when the WMSGetFeatureInfo > request goes through to GeoWebCache it is like it's using the default 72 for > DOTS_PER_INCH, because all of the resolutions are about 21% out. > > GeoWebCache responds with messages such as :"400: Requested horizontal > resolution: 0.54931640625 , best match: 0.703125 exceeds 10% threshold. > Perhaps the client is configured with an incorrect set of scales > (resolutions), or the DPI setting is off compared to the one in GWC ?" > > I've actually just dropped the WMSGetFeatureInfo control into a GeoWebCache > OpenLayers demo, so the resolutions are definitely set up to match. The full > source (pretty short and simple) is at http://pastebin.com/JENnAPC9. > > I've brought it up on the GeoWebCache mailing list but now thinking that it's > more likely something to do with OpenLayers. Here's a link to my messages: > http://tinyurl.com/38jvcva > > It seems like the resolution would be calculated incorrectly by about that > amount if the DOTS_PER_INCH were still at 72, so I'm wondering if there's > another setting that I need to change or if there's a bug somewhere. > > Your comments are appreciated. > > Regards, > > Miles Jordan > Acting Manager / Systems Analyst > Australian Antarctic Data Centre > Australian Antarctic Division > Dept. of the Environment, Water, Heritage & the Arts > > > > ___________________________________________________________________________ > > Australian Antarctic Division - Commonwealth of Australia > IMPORTANT: This transmission is intended for the addressee only. If you are > not the > intended recipient, you are notified that use or dissemination of this > communication is > strictly prohibited by Commonwealth law. If you have received this > transmission in error, > please notify the sender immediately by e-mail or by telephoning +61 3 6232 > 3209 and > DELETE the message. > Visit our web site at http://www.antarctica.gov.au/ > ___________________________________________________________________________ > _______________________________________________ > Users mailing list > Users@openlayers.org > http://openlayers.org/mailman/listinfo/users -- Andreas Hocevar OpenGeo - http://opengeo.org/ Expert service straight from the developers. _______________________________________________ Users mailing list Users@openlayers.org http://openlayers.org/mailman/listinfo/users
