[OpenLayers-Users] WMS layer with different SRS than basemap

[Guillaume Sueur]

Good to hear !

Now, don't try to display really different projections on your map,
cause it would me a mess Openlayers could not handle anymore ;-)

Guillaume

Dejung Gewissler a écrit :
> Thanks! That worked great.
> 
> Guillaume Sueur wrote:
>> Hi,
>>
>> This is the answer I got from Chris few months ago when I asked for the
>> same question :
>> OpenLayers does not support the display of differently projected WMS
>>   
>>>> layers. I'm assuming that in this case, your two different projection
>>>> strings have the same projection, and that this isn't actually two
>>>> different projections like OpenLayers tries to helpfully assume it is.
>>>> If that's the case, then the code to modify is the getFullRequestString
>>>> function: specifically, doing something like this:
>>>>
>>>> OpenLayers.Layer.WMS.prototype.getFullRequestString =
>>>>            function(newParams, altUrl) {
>>>>      var projectionCode = this.projection.toString();
>>>>      this.params.SRS = (projectionCode == "none") ? null :
>>>>       
>> projectionCode;
>>   
>>>>      return OpenLayers.Layer.Grid.prototype.getFullRequestString.apply(
>>>>        this, arguments);
>>>> }
>>>>       
>> this should avoid map projection override of layer's specific projection
>>
>> Hope that helps
>>
>> Guillaume
>>
>> Dejung Gewissler a écrit :
>>   
>>> Hi All-
>>>
>>> I've searched on Nabble for the answer to this to no avail. I know you 
>>> all are busy with the release cycle (!kudos to all that are involved!), 
>>> but I was hoping someone has an easy answer for this problem.
>>>
>>> I've got some WMS services coming from IMS or ArcGIS servers and some 
>>> others coming from GeoServer. Unfortunately ESRI identifies the NJ State 
>>> Plane (us feet) coordinate system as EPSG:102711 and GeoServer uses 
>>> EPSG:3432. ESRI doesn't have a EPSG:3432 and GeoServer doesn't have a 
>>> EPSG:102711!!! I understand that OpenLayers doesn't support raster 
>>> reprojection because it would be nearly impossible to do in a browser, 
>>> etc. My images, however, are fundamentally of the same projection, 
>>> albeit with a different SRS identifier. I just need them laid on top of 
>>> each other.
>>>
>>> I define my map with options {... projection: 'EPSG:102711' ...} and my 
>>> WMS overlays with {... srs: 'EPSG:3432' ...}. The WMS overlays are 
>>> nonetheless being sent with SRS=EPSG:102711. It seems that OL ignores 
>>> the passed-in srs in the layer constructor and defaults to whatever the 
>>> baselayer's projection is. That makes sense in stopping the raster 
>>> reprojection train, but poses a problem in my situation. Is there a way 
>>> to force the SRS change of a WMS overlay?
>>>
>>> Thanks,
>>> Dejung
>>> _______________________________________________
>>> Users mailing list
>>> Users at openlayers.org
>>> http://openlayers.org/mailman/listinfo/users
>>>
>>>
>>>     
>>