Is there a chance to set an alpha-mask using XOrg?

[Graeme Gill]

Peter Harris wrote:
> It depends on your toolkit. If you're not using any particular toolkit,
> the easiest way is to set _NET_WM_WINDOW_OPACITY on your window. See
> http://webcvs.freedesktop.org/xapps/transset/transSet.c?view=markup for
> an example.

I notice (from finding out the hard way) that this is not documented
in any  formal fashion (ie. it's not in 
<http://standards.freedesktop.org/wm-spec/wm-spec-1.4.html>).
It would probably be a good idea to document such things, so that
developers might more easily discover them.

cheers,

Graeme Gill.