[Mapserver-dev] non-square pixels and WMS

[Frank Warmerdam]

Steve Lime wrote:
> Thanks for adding this support.  Is the intent to not require the user
> to set this in the case of WMS and WCS? I mean, should
> we just set the flag for the user within those interfaces?

Steve,

If we find the mode works well, it might well make sense to turn it on by
default in the WMS cases.  I think we completely avoid msDrawMap() in the WCS
code, so we will have to do some extra steps there to enable non-square
pixels or rotation.  The good news on the WCS side is that we only have to
worry about raster layers which support the geotransform properly so there is
no side effects to worry about.

I would also stress that like rotation, for non-square pixels you currently
need to have a proper projection set on every layer *and* the map as a
(potentially unnecessary) trip through the projection code is used to apply
the geotransform.

In fact, due to this side effect I would hesitate to make non-square support
the default for the time being - even in WMS mode.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent