Re: [udig-devel] A bit more forgiving on layer graphics ...

[Richard Gould <rgould@xxxxxxxxxxxxxxx>]

What about displaying the full image returned from those requests in a 
tool-tip-like popup?

Richard

Jody Garnett wrote:
> Those following udig development may remember a time when more legend 
> graphics showed up.
> This is due to a conflicting world view we have with the WMS spec. It 
> provides *legend* graphics were we really need *layer* graphics for udig.
>
> Here is a snapshot of a patch that is a bit more forgiving on legend 
> graphics not being the requested size ...
>
>
>
> To illustrate the "problem" here are some sample legend graphic requests 
> used above:
>
> A themed glyph from mapserver:
> <http://dev1.dmsolutions.ca/cgi-bin/mswms_gmap?REQUEST=GetLegendGraphic&LAYER=popplace&STYLE=&FORMAT=image/png&WIDTH=16&VERSION=1.0.0&HEIGHT=16&SERVICE=WMS>
>
> A couple glyph w/ text layers from mapserver:
> <http://dev1.dmsolutions.ca/cgi-bin/mswms_gmap?REQUEST=GetLegendGraphic&LAYER=road&STYLE=&FORMAT=image/png&WIDTH=16&VERSION=1.0.0&HEIGHT=20&SERVICE=WMS>
> <http://dev1.dmsolutions.ca/cgi-bin/mswms_gmap?REQUEST=GetLegendGraphic&LAYER=park&STYLE=&FORMAT=image/png&WIDTH=16&VERSION=1.0.0&HEIGHT=16&SERVICE=WMS>
>
> And finally a themed layer from cubserver (they draw it in a box!)
> <http://test-dw.ccrs.nrcan.gc.ca:9090/cubewerx/cubeserv/cubeserv.cgi?REQUEST=GetLegendGraphic&LAYER=CANADNACB_L:CEOWARE2&STYLE=&FORMAT=image/png&WIDTH=16&VERSION=1.0.0&HEIGHT=16&SERVICE=WMS>
>
> What I have done is:
> 1) return any image that is 16x16 (it does happen)
> 2) scale up to 16 x 16 any image that is too small
> 3) if a mask is available trying and skip any masked lines then columns, 
> before extracting a 16x16 swatch
> 4) if an alpha is available trying to skip any clear lines then columns, 
> before extracting a 16x16 swatch
> 5) skip any while lines then columns, before extracting a 16x16 swatch
>
> I also experimented with simply:
> - grabbing the first 16x16 swatch (always worked, no possibility of 
> looking right)
> - resizing a square based on min width or height (looked great for non 
> themed legend graphics)
>
> Jody
>
>
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