[OpenLayers-Users] Getting values from a WMS with GeoTiff file

[Riccardo Di Stefano]

I made some more tests: debugging GeoExplorer (which uses OpenLayers) with
Firefox debugger, I see that the following GetFeatureInfo request is sent:

http://localhost:8080/geoserver/ows?LAYERS=ENDORSE:ENDORSE_BNI&QUERY_LAYERS=
ENDORSE:ENDORSE_BNI&STYLES=&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo
&BBOX=-7612907.636721%2C1665802.66581%2C11133120.673553%2C5931600.339756&FEA
TURE_COUNT=10&HEIGHT=436&WIDTH=1916&FORMAT=image/png&INFO_FORMAT=application
/vnd.ogc.gml&SRS=EPSG:900913&X=866&Y=285

The WMS answers correctly; here is the XML I get:

<?xml version="1.0" encoding="UTF-8"?>
                <wfs:FeatureCollection xmlns="http://www.opengis.net/wfs"
xmlns:wfs="http://www.opengis.net/wfs"
xmlns:ENDORSE="http://opengeo.org/#ENDORSE"
xmlns:gml="http://www.opengis.net/gml"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.opengis.net/wfs
http://localhost:8080/geoserver/schemas/wfs/1.0.0/WFS-basic.xsd">
                                <gml:boundedBy>
                                                <gml:null>unknown</gml:null>
                                </gml:boundedBy>
                                <gml:featureMember>
                                                <ENDORSE:ENDORSE_BNI fid="">
 
<ENDORSE:GRAY_INDEX>2295.0</ENDORSE:GRAY_INDEX>
                                                </ENDORSE:ENDORSE_BNI>
                                </gml:featureMember>
                </wfs:FeatureCollection>


2295.0 is the correct value for the my lat/lon.
I should be able to do the same with my code, but I just don't know how...
Any advices?

Thank you again!

-----Original Message-----
From: Diego Guidi [mailto:diegoguidi at gmail.com] 
Sent: giovedì 5 dicembre 2013 12:24
To: Riccardo Di Stefano
Cc: openlayers-users at lists.osgeo.org
Subject: Re: [OpenLayers-Users] Getting values from a WMS with GeoTiff file

On Thu, Dec 5, 2013 at 12:09 PM, Riccardo Di Stefano
<riccardo.distefano at i-em.eu> wrote:
> I have to query values of a WMS hosted by Geoserver from a GeoTiff file.
You're working with a raster  (i.e an image) so AFAIK there are no ways to
extract information from a data source like this via a GetFeatureInfo,
because ecutally there isn't information to read.
You can extract information from vector data like shapefiles.



Diego Guidi