Re: [gtk-list] transparent popups?

[Owen Taylor <owt1 cornell edu>]

If you want to do this kind of stuff, you'll probably be dealing more
with gdk than with gtk, and you might even have to add some X calls.

I'm no expert, but to have "transparent" popups, you'll need to use
the Shaped window extension to X. To do this, you'll probably have to
make some direct calls down into X (or extend GDK...) If you are going
to do this <gdk/gdkx.h> has some macros that allow you to get low
level.

For drawing on the root window, you may find the
gdk_window_foreign_new() function added in gtk+970915 useful.  It
creates a surrogate gdk window for an arbitrary X window.  So after
including the above <gdk/gdkx.h>, you could do

  root_window = gdk_window_foreign_new (GDK_ROOT_WINDOW());

and then use all the gdk drawing calls on root_window.

All this stuff, of course, breaks the encapsulation of X within GDK,
but it probably is inherently non-portable anyways...

Regards,
                                        Owen