[OpenLayers-Users] No imagery message tile like Google Maps

[Paul Spencer]

Since you are hitting mapserver anyway to generate the error message,  
you might as well have it generate the no data tile:

LAYER
   NAME "nodata"
   STATUS ON
   TYPE ANNOTATION
   TRANSFORM FALSE # feature is in pixel space, not geographic space
   FEATURE
     POINTS
       128 128 # middle of a 256x256 tile draw
     END
     TEXT "No Data Available"
   END
   CLASS
     MINSCALE 1
     MAXSCALE 20000 # below this scale, there is no data
     LABEL
       FONT "arial" #defined in fonts.txt
       TYPE TRUETYPE
       SIZE 8
       BUFFER 1
       COLOR 0 0 0
       BACKGROUND 255 255 255
       FORCE TRUE
     END
   END
END

(adapted from http://mapserver.gis.umn.edu/docs/faq/copyright-layer)

Cheers

Paul

On 7-May-08, at 12:30 PM, zenzero-2001 wrote:
>
> Hi,
>
> I couldn't get it to work. But I know why. It is because the  
> MapServer WMS
> is not returning an error, it always returns a valid map, even it is  
> just
> blank.
>
> So I need to make certain scales invalid so that when a WMS request  
> is made
> for a scale that is not supported it returns an error instead of  
> blankness.
> I've had a look at the WMS information on the MapServer website and  
> I can't
> see how to do this. There is "wms_extent" for defining the bounding  
> box, but
> nothing for scales.
>
> Thanks.
> -- 
> View this message in context: http://www.nabble.com/No-imagery-message-tile-like-Google-Maps-tp17105133p17109121.html
> Sent from the OpenLayers Users mailing list archive at Nabble.com.
>
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