[Geoserver-users] GetFeatureInfo not working at certain zoom level

GeoServer GeoServer User
1

Hi,

I'm using GeoServer 2.0 and somehow the GetFeatureInfo request is not
working at certain zoom level.
We are displaying schools as points in the map, but when we zoom in and
click on one of the points we don't get any information back. But if we
zoom out is working fine.

I was reading that there's a tolerance or radio parameter for this
request but couldn't find any info.
Any ideas ?

thanks

--
Jorge Bächler O.

Arbol Logika S.A
Tel: 465 3889
Fax: 465 3889
http://www.arbol-logika.com

2

Any idea ? please help..

thanks

Jorge Bächler O.

Arbol Logika S.A
Tel: 465 3889
Fax: 465 3889
http://www.arbol-logika.com

Jorge Bachler Olmos wrote:

Hi,

I'm using GeoServer 2.0 and somehow the GetFeatureInfo request is not
working at certain zoom level.
We are displaying schools as points in the map, but when we zoom in and
click on one of the points we don't get any information back. But if we
zoom out is working fine.

I was reading that there's a tolerance or radio parameter for this
request but couldn't find any info.
Any ideas ?

thanks

3

Hi Jorge, I know that the GetFeatureInfo creates a URL like this one:

http://giswebservices.massgis.state.ma.us/geoserver/wms?VERSION=1.1.1&REQUEST=GetFeatureInfo&LAYERS=massgis:GISDATA.ACECS_POLY&SRS=EPSG:26986&BBOX=11830.0,776202.9449152543,348201.0,961492.0550847457&WIDTH=708&HEIGHT=390&INFO_FORMAT=text/html&FEATURE_COUNT=100&QUERY_LAYERS=massgis:GISDATA.ACECS_POLY&X=120&Y=109&FORMAT&STYLES=

where there is a bounding box. Can you see the URL that your GetFeatureInfo is producing?
Can you verify that the school's coordinate falls inside the bounding box?
Perhaps your client (OpenLayers?) is not calculating the bbox correctly or something?

________________________________________
From: geoserver-users-bounces@lists.sourceforge.net [geoserver-users-bounces@lists.sourceforge.net] On Behalf Of Jorge Bachler Olmos [jorge@anonymised.com]
Sent: Friday, January 22, 2010 10:33 AM
To: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] GetFeatureInfo not working at certain zoom level

Any idea ? please help..

thanks

Jorge Bächler O.

Arbol Logika S.A
Tel: 465 3889
Fax: 465 3889
http://www.arbol-logika.com

Jorge Bachler Olmos wrote:

Hi,

I'm using GeoServer 2.0 and somehow the GetFeatureInfo request is not
working at certain zoom level.
We are displaying schools as points in the map, but when we zoom in and
click on one of the points we don't get any information back. But if we
zoom out is working fine.

I was reading that there's a tolerance or radio parameter for this
request but couldn't find any info.
Any ideas ?

thanks

------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

4

Hi,

BBOX is misleading here, it is just copied from GetMap request. GetFeaturInfo query is done by parameters X= and Y= which present pixel coordinates. Thus it is a point, but WMS server can widen the point to area by introducing a tolerance. Then it is easier to hit a point feature with GetFeatureInfo request. Mapserver is having a TOLERANCE keyword for controlling this, I do not know if Geoserver has a similar kind of control somewhere.

-Jukka Rahkonen-

-----Alkuperäinen viesti-----
Lähettäjä: Freeman, Aleda (EEA) [mailto:Aleda.Freeman@anonymised.com]
Lähetetty: pe 22.1.2010 17:39
Vastaanottaja: Jorge Bachler Olmos; geoserver-users@lists.sourceforge.net
Aihe: Re: [Geoserver-users] GetFeatureInfo not working at certain zoom level

Hi Jorge, I know that the GetFeatureInfo creates a URL like this one:

http://giswebservices.massgis.state.ma.us/geoserver/wms?VERSION=1.1.1&REQUEST=GetFeatureInfo&LAYERS=massgis:GISDATA.ACECS_POLY&SRS=EPSG:26986&BBOX=11830.0,776202.9449152543,348201.0,961492.0550847457&WIDTH=708&HEIGHT=390&INFO_FORMAT=text/html&FEATURE_COUNT=100&QUERY_LAYERS=massgis:GISDATA.ACECS_POLY&X=120&Y=109&FORMAT&STYLES=

where there is a bounding box. Can you see the URL that your GetFeatureInfo is producing?
Can you verify that the school's coordinate falls inside the bounding box?
Perhaps your client (OpenLayers?) is not calculating the bbox correctly or something?

________________________________________
From: geoserver-users-bounces@lists.sourceforge.net [geoserver-users-bounces@lists.sourceforge.net] On Behalf Of Jorge Bachler Olmos [jorge@anonymised.com]
Sent: Friday, January 22, 2010 10:33 AM
To: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] GetFeatureInfo not working at certain zoom level

Any idea ? please help..

thanks

Jorge Bächler O.

Arbol Logika S.A
Tel: 465 3889
Fax: 465 3889
http://www.arbol-logika.com

Jorge Bachler Olmos wrote:

Hi,

I'm using GeoServer 2.0 and somehow the GetFeatureInfo request is not
working at certain zoom level.
We are displaying schools as points in the map, but when we zoom in and
click on one of the points we don't get any information back. But if we
zoom out is working fine.

I was reading that there's a tolerance or radio parameter for this
request but couldn't find any info.
Any ideas ?

thanks

------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users
------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

5

Oh, right - I forgot about the x and y.
I think there was tolerance discussed at some point, let me see if I can find a reference.

________________________________________
From: Rahkonen Jukka [Jukka.Rahkonen@anonymised.com]
Sent: Friday, January 22, 2010 11:30 AM
To: Freeman, Aleda (EEA); Jorge Bachler Olmos; geoserver-users@anonymised.comforge.net
Subject: Re: [Geoserver-users] GetFeatureInfo not working at certain zoom level

Hi,

BBOX is misleading here, it is just copied from GetMap request. GetFeaturInfo query is done by parameters X= and Y= which present pixel coordinates. Thus it is a point, but WMS server can widen the point to area by introducing a tolerance. Then it is easier to hit a point feature with GetFeatureInfo request. Mapserver is having a TOLERANCE keyword for controlling this, I do not know if Geoserver has a similar kind of control somewhere.

-Jukka Rahkonen-

-----Alkuperäinen viesti-----
Lähettäjä: Freeman, Aleda (EEA) [mailto:Aleda.Freeman@anonymised.com]
Lähetetty: pe 22.1.2010 17:39
Vastaanottaja: Jorge Bachler Olmos; geoserver-users@lists.sourceforge.net
Aihe: Re: [Geoserver-users] GetFeatureInfo not working at certain zoom level

Hi Jorge, I know that the GetFeatureInfo creates a URL like this one:

http://giswebservices.massgis.state.ma.us/geoserver/wms?VERSION=1.1.1&REQUEST=GetFeatureInfo&LAYERS=massgis:GISDATA.ACECS_POLY&SRS=EPSG:26986&BBOX=11830.0,776202.9449152543,348201.0,961492.0550847457&WIDTH=708&HEIGHT=390&INFO_FORMAT=text/html&FEATURE_COUNT=100&QUERY_LAYERS=massgis:GISDATA.ACECS_POLY&X=120&Y=109&FORMAT&STYLES=

where there is a bounding box. Can you see the URL that your GetFeatureInfo is producing?
Can you verify that the school's coordinate falls inside the bounding box?
Perhaps your client (OpenLayers?) is not calculating the bbox correctly or something?

________________________________________
From: geoserver-users-bounces@lists.sourceforge.net [geoserver-users-bounces@lists.sourceforge.net] On Behalf Of Jorge Bachler Olmos [jorge@anonymised.com]
Sent: Friday, January 22, 2010 10:33 AM
To: geoserver-users@lists.sourceforge.net
Subject: Re: [Geoserver-users] GetFeatureInfo not working at certain zoom level

Any idea ? please help..

thanks

Jorge Bächler O.

Arbol Logika S.A
Tel: 465 3889
Fax: 465 3889
http://www.arbol-logika.com

Jorge Bachler Olmos wrote:

Hi,

I'm using GeoServer 2.0 and somehow the GetFeatureInfo request is not
working at certain zoom level.
We are displaying schools as points in the map, but when we zoom in and
click on one of the points we don't get any information back. But if we
zoom out is working fine.

I was reading that there's a tolerance or radio parameter for this
request but couldn't find any info.
Any ideas ?

thanks

------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users
------------------------------------------------------------------------------
Throughout its 18-year history, RSA Conference consistently attracts the
world's best and brightest in the field, creating opportunities for Conference
attendees to learn about information security's most important issues through
interactions with peers, luminaries and emerging and established companies.
http://p.sf.net/sfu/rsaconf-dev2dev
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

6

It looks like it's possible: http://jira.codehaus.org/browse/GEOS-1434

7

It works! If I add a &buffer=50 at the end:

http://giswebservices.massgis.state.ma.us/geoserver/wms?VERSION=1.1.1&REQUEST=GetFeatureInfo&LAYERS=massgis:GISDATA.ACECS_POLY&SRS=EPSG:26986&BBOX=11830.0,776202.9449152543,348201.0,961492.0550847457&WIDTH=708&HEIGHT=390&INFO_FORMAT=text/html&FEATURE_COUNT=100&QUERY_LAYERS=massgis:GISDATA.ACECS_POLY&X=120&Y=109&FORMAT&STYLES=&buffer=50

I get two features back instead of 1, so I widened the tolerance there...

________________________________________
From: Freeman, Aleda (EEA) [Aleda.Freeman@anonymised.com]
Sent: Friday, January 22, 2010 11:35 AM
To: Freeman, Aleda (EEA); Rahkonen Jukka; Jorge Bachler Olmos; geoserver-users@lists.sourceforge.net
Subject: RE: [Geoserver-users] GetFeatureInfo not working at certain zoom level

It looks like it's possible: http://jira.codehaus.org/browse/GEOS-1434

8

Thanks !

Jorge Bächler O.

Arbol Logika S.A
Tel: 465 3889
Fax: 465 3889
http://www.arbol-logika.com

Freeman, Aleda (EEA) wrote:

It works! If I add a &buffer=50 at the end:

http://giswebservices.massgis.state.ma.us/geoserver/wms?VERSION=1.1.1&REQUEST=GetFeatureInfo&LAYERS=massgis:GISDATA.ACECS_POLY&SRS=EPSG:26986&BBOX=11830.0,776202.9449152543,348201.0,961492.0550847457&WIDTH=708&HEIGHT=390&INFO_FORMAT=text/html&FEATURE_COUNT=100&QUERY_LAYERS=massgis:GISDATA.ACECS_POLY&X=120&Y=109&FORMAT&STYLES=&buffer=50

I get two features back instead of 1, so I widened the tolerance there...

________________________________________
From: Freeman, Aleda (EEA) [Aleda.Freeman@anonymised.com]
Sent: Friday, January 22, 2010 11:35 AM
To: Freeman, Aleda (EEA); Rahkonen Jukka; Jorge Bachler Olmos; geoserver-users@lists.sourceforge.net
Subject: RE: [Geoserver-users] GetFeatureInfo not working at certain zoom level

It looks like it's possible: http://jira.codehaus.org/browse/GEOS-1434