Detecting whether a compositing manager is running

[Alexander Larsson]

On Mon, 2005-09-19 at 10:59 +0200, Christian Neumair wrote:
> Am Sonntag, den 18.09.2005, 13:22 -0400 schrieb Havoc Pennington:
> > On Fri, 2005-09-16 at 09:59 +0200, Christian Neumair wrote:
> > > It can be useful for applications and desktop environments to detect
> > > whether an application manager is running, for instance to decide
> > > whether it should use the rgba visual. According to Matthias Clasen,
> > > there are no means to detect this as of writing [1]. Maybe we should
> > > have a per-Screen flag which returns whether a compositing manager is
> > > running for that particular Screen.
> > > Opinions?
> > > 
> > 
> > Having a compositing manager selection makes sense, but choosing a
> > visual based on whether a CM is running seems very broken to me. 
> > What if your app starts before the CM, or what if there's no CM at first
> > and someone runs one later? There's no way to change the visual
> > retroactively.
> 
> I want semi-transparent drag icons for Nautilus. I'd composite all
> icon-representing GdkPixbufs together into a big RGBA pixbuf. Because a
> shape bitmask is also applied to the drag window, the worst that can
> happen is that users have icon-shaped opaque drag icons.

Gtk 2.8 already does alpha pixbufs for drag icons. Its done using the
the argb cursors extenstion. Unfortunately the size of cursor limits the
size of the cursor. Its implementation-specific, but on my box maxes out
at 64x64, so its not working for the case of nautilus...

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
                   alexl at redhat.com    alla at lysator.liu.se 
He's an underprivileged sweet-toothed dog-catcher on the edge. She's a 
time-travelling mute fairy princess from Mars. They fight crime!