[Fwd: Re: [UMN_MAPSERVER-DEV] single classed layers and GetLegendGraphic]

[Bart van den Eijnden]

For reference, this was my original post on the wms-dev list.

http://lists.eogeo.org/pipermail/wms-dev/2004-May/000518.html

The answer Keith gave only applied to the case of multiple rules, but I
did not suspect this behaviour to be different from the case where there
is only one rule ... but apparently it is in Cubewerx's implementation ...

I do see Tom has a point now, but still think the spec is not fully
well-thought at the moment ...

Tom, btw what is your purpose for only getting the legend graphic without
a label in the case of a single class layer? Are you putting the wms_title
next to the legend graphic in the WMS client (or using no label at all?),
because otherwise you need to know the name of the Rule anyway to put it
next to the legend graphic (and use a GetStyles request to know this
name).

Btw2: does Cubewerx use the GetLegend request in their LegendURL?

Best regards,
Bart

>> As I wrote already, I agree that this may be a valid
>> interpretation, and
>> that was our initial interpretation of the spec. However the spec is
>> vague on this and in bug 653 it was requested that we align
>> MapServer's
>> behavior with other (prior) implementations (cubeserv) so
>> that clients
>> can better interoperate.
>>
>
> Here are my CubeSERV observations:
>
> CubeSERV OGC:WMS 1.1.1 GetLegendGraphic requests:
>
> This is a layer with multiple classes:
>
> http://ceoware2.ccrs.nrcan.gc.ca/cubewerx/cubeserv/cubeserv.cgi?service=
> WMS&version=1.1.1&request=GetLegendGraphic&layer=CANADNAODA_L%3ACEOWARE2
> &format=image/png
>
> This is a layer with a single class (i.e. all point symbols are the
> same)
>
> http://ceoware2.ccrs.nrcan.gc.ca/cubewerx/cubeserv/cubeserv.cgi?version=
> 1.1.1&service=WMS&request=GetLegendGraphic&layer=GCDB_INDEX:CEOWARE2&for
> mat=image/png
>
> The layer title does not show up as part of the image.  This is default
> behaviour.
>
> Here is the same layer (single class) with the layer name embedded in
> image via 'GetLegend'
>
> http://ceoware2.ccrs.nrcan.gc.ca/cubewerx/cubeserv/cubeserv.cgi?version=
> 1.1.1&service=WMS&request=GetLegend&layers=GCDB_INDEX:CEOWARE2&format=im
> age/png
>
> Here are both layers in a GetLegend:
>
> http://ceoware2.ccrs.nrcan.gc.ca/cubewerx/cubeserv/cubeserv.cgi?version=
> 1.1.1&service=WMS&request=GetLegend&layers=GCDB_INDEX:CEOWARE2,CANADNAOD
> A_L:CEOWARE2&format=image/png
>
> ..Tom
>
>