[Cogl] Is there an X window named "." created when using Cogl/Clutter with GLES/EGL/X11?

[Robert Bragg]

Hi Reza,

Cogl creates a dummy 1x1 window positioned at (-100,-100) that is
never mapped by Cogl. This is created because GLX doesn't let you
interact with a GL context unless it is associated with a drawable and
we want to interact with GL before your application explicitly creates
a window/stage.

I'm not sure why you would ever be seeing this window though, since it
is never mapped by Cogl, so maybe the window you are seeing is created
by something else. Also Cogl doesn't set any window manager hints to
give that dummy window a title of "." so that also makes me guess this
dummy window isn't made by Cogl. B.t.w how are you determining that
the window is named "." are you seeing a window manager frame and
title for that window? That certainly shouldn't happen for the Cogl
dummy window, even if it did some how get mapped then the window is
marked as override-redirect and so the window manager should basically
ignore it.

Perhaps you can set some breakpoints on XCreateWindow,
XCreateSimpleWindow and XMapWindow to see what other things are
creating X windows and mapping them.

Regards,
Robert


On Tue, Apr 15, 2014 at 7:36 PM, Reza Ghassemi <reza.robin1 at gmail.com> wrote:
> Hi,
> We have an issue where an X window named "." of the same size and position
> of our main window is created when launching our Clutter app and we don't
> know who is creating it.  On this system we need to unmap this window along
> with the main window when our app suspends itself to avoid input going to
> this "dummy" which appears to be below our main window.  I see some code in
> the WGL implementation referring to a window named "." but not in EGL.  Any
> ideas?
>
> We're kinda in a hurry to fix this.
>
> Thanks,
> Reza