Legend size calculation, WMS LegendURL size
Steve.Lime at DNR.STATE.MN.US
Wed Dec 12 19:56:50 EST 2007
Hi Shawn: Thanks for the contribution! Should probably create a ticket and attach the
patch there. I can apply but I'd like to hear from some of the OGC gurus out there first
as this is not my area of expertise.
>>> Shawn Gervais <project10 at PROJECT10.NET> 12/11/07 4:40 PM >>>
I have attached a patch which:
- Refactors legend size calculation out of msDrawLegend and into its
- Uses the legend size calculating function to better estimate the
height/width of LegendURLs advertised in GetCapabilities responses
There seems (to me) to be some ambiguity in the WMS specs regarding
LegendURL. WMS 1.3.0 clears this up a lot, and states (03-109r1, 188.8.131.52.5):
"Servers should provide the width and height attributes if known at the
time of processing the GetCapabilities request."
And WMS 1.3.0 makes those attributes optional. However, under WMS 1.1.1
MapServer advertises a GetLegendGraphic-using OnlineResource for the
LegendURL, but provides dimensions that are only sufficient for drawing
the legend 'key', but not the label.
Of course, the dimensions will (potentially) be incorrect if the client
issues RULE or SCALE parameters, but they should be correct for the URL
that is advertised.
Any comments? Flames?
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