Re: override_redirect of X Window System

[Jan D.]

> 
> Hello,
> 
> I have one request for Emacs 21.
> 
> I'm now creating a presentation tool for Emacs 21. One problem is that
> there is no way to set one frame attribute "override_redirect" to
> True.
> 
> Imagine that we try to create a frame which overs the entire screen
> for presentation. Since we can't set override_redirect to True, the
> created frame can't cover the entire screen unders some window
> managers including gnome.
> 
> Thus I would like to a method to set override_redirect to True. One
> idea is extend modify-frame-parameters to handle override_redirect.

I do not think this is a good idea to accomplish what you want.  First,
to handle thie properly (as in ICCCM compliance), we would have to grab
both the pointer and the keyboard.  And if Emacs hangs, you have to exit
X.  Also, there can be no switching to other applications.  There are
probably other nasty side effects I haven't thought about.

It is true that Metacity (the current Gnome window manager) does not
allow you to move windows above the screen (i.e. y coordinate less than
zero), but this is a Metacity bug.  Maybe you can run another window manager?
Some that even allows you to specify that the window in question shall
have no decorations at all (most except Metacity can handle this)?

        Jan D.