[Mapserver-users] WMS BBOX vs. Actual Bounds

[Daniel Morissette]

Ed McNierney wrote:
> Ian -
> 
> How is it possible to honor all parameters when they are not consistent?
> I certainly understand the need to deal with unusual output devices as
> you describe, but it is not very difficult for the client to address
> that situation.
> 

I don't know if specifying a SRS+BBOX with a width/height ration that 
doesn't match the WIDTH/HEIGHT should be called consistent or not, but 
it is a valid request according to the specs.  While I would discourage 
the generation of such requests in general I can understand why it would 
be legitimate for some clients to request that, for instance if the 
device has non-square pixels. Unfortunately significant changes would be 
required to support that in MapServer, that's why we haven't done it yet.

Now, back to the original problem that was reported, if the client makes 
sure that the width/height in the BBOX matches the WIDTH/HEIGHT value in 
the GetMap request, then what they get is fully predictable.

Daniel
-- 
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  Daniel Morissette               morissette at dmsolutions.ca
  DM Solutions Group              http://www.dmsolutions.ca/
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