Jacolin Yves wrote:
Le Tuesday 07 August 2007 14:37:59 Daniel Morissette, vous avez écrit :
If you are using MapServer as a WMS service and expecting the
transparency/opacity of a given layer to result in a 50% opaque GetMap
response then that won't work.
...
Is it a limitation from mapserver or from the standard itself?
It's a bit of both.
The WMS spec is not clear on whether it is acceptable to return
semi-transparent images. Section 7.2.3.9 of the WMS 1.1.1 spec talks
about the TRANSPARENT=TRUE/FALSE GetMap parameter but that is only to
control whether the background of the image is fully transparent or not
and does not address the possibility of producing semi-transparent
images. Everywhere else it suggests that pixels representing features
are fully opaque.
And it may also be a MapServer limitation in the sense that we may need
to make some changes to allow MapServer to generate semi-transparent
images... but maybe not and that works already, I just haven't checked.
Daniel
--
Daniel Morissette
http://www.mapgears.com/
