[OpenLayers-Dev] GetFeature control question

[Bart van den Eijnden]

I think I am missing this up with WMS GetFeatureInfo, where the server does have to do a best match.

Sorry for the noise.

Best regards,
Bart

On Feb 6, 2010, at 8:55 PM, Andreas Hocevar wrote:

> bartvde at osgis.nl wrote:
>> Andreas,
>> 
>> but why do you not leave the best match up to the WFS by specifying
>> maxFeatures 1? What is the purpose/advantage of doing this client-side?
>>  
> 
> Where does the WFS spec say that setting maxFeatures to 1 will return the best matching feature? Usually that returns the first one matching the filter condition.
> 
> Regards,
> Andreas.
> 
>> Best regards,
>> Bart
>> 
>>  
>>> Eric Lemoine wrote:
>>>    
>>>> On Mon, Jan 11, 2010 at 3:22 PM, Bart van den Eijnden <bartvde at osgis.nl>
>>>> wrote:
>>>> 
>>>>      
>>>>> Hi list,
>>>>> 
>>>>> I am failing to understand the following line in
>>>>> OpenLayers.Control.GetFeature:
>>>>> 
>>>>> maxFeatures: options.single == true ? this.maxFeatures : undefined,
>>>>> 
>>>>> I would expect it to be:
>>>>> 
>>>>> maxFeatures: options.single == true ? 1: this.maxFeatures,
>>>>> 
>>>>> so if we only want a single feature, have it set to 1, otherwise use
>>>>> the maxFeatures given by the application designer.
>>>>> 
>>>>>        
>>>> I'd make more sense to me too.
>>>> 
>>>>      
>>> You are looking at this line without the context. There is also:
>>> 
>>> if(options.single == true) {
>>>    this.selectBestFeature(result.features,
>>>    bounds.getCenterLonLat(), options);
>>> } else {
>>>    this.select(result.features);
>>> }
>>> 
>>> One of the key advantages of the GetFeature control over WMSGetFeature
>>> is that it will *always* just return *one single feature* on a click,
>>> and this feature will be the *best matching one*. The maxFeatures config
>>> option is just about how many features to use to determine the best
>>> matching one. Maybe this should be documented better.
>>> 
>>> Regards,
>>> Andreas.
>>> 
>>> --
>>> Andreas Hocevar
>>> OpenGeo - http://opengeo.org/
>>> Expert service straight from the developers.
>>> 
>>> 
>>>    
>> 
>> 
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>>  
> 
> 
> -- 
> Andreas Hocevar
> OpenGeo - http://opengeo.org/
> Expert service straight from the developers.
> 
>