[EWMH] _NET_WM_WINDOW_TYPE_AUXILIARY

[Denis Washington <dwashington gmx net>]

Hello,

A few days ago I wrote a small patch to add a more fancy launcher
feedback animation to the GNOME panel when a compositing manager is
running [1]. For this animation, I'm using an auxiliary ARGB window into
which I draw the actual animation (a ghost effect which expands over the
panel area and thus needs an extra window). This works quite well,
however there is one problem: most compositing managers (I tried with
compiz) apply animations on mapped and unmapped windows, which takes
away the full control over the effect from me. For my effect, for
instance, the problem is that my compiz configuration does a fade-in on
my auxiliary windows although I actually want to start with a fully
opaque window fading out; the result is the window fading in while I am
already starting to fade it out from my code, leading to more like a
flash than a proper fade-out.

My proposal is to add a new window type hint, say
_NET_WM_WINDOW_TYPE_AUXILIARY (maybe not the best name), which tells
window managers not to apply any animations to it so that applications
have full control over on how they will look when appearing,
disappearing etc. I'm convinced that there are also plenty of other
effects for which this would be quite handy.

Regards,
Denis Washington

[1] Bug 479562 – [PATCH] Fancier launcher animation if compositing
manager is running (gnome-panel),
http://bugzilla.gnome.org/show_bug.cgi?id=479562