Can u share the code somehow ?
GeditOverlay does something like this, but way more restricted.
And I do have a question: Can I stack GtkLayout widgets in your implementation ?
I have crated a gtkstacked widget so I can have different layer on it.
/* Creates a new button with the label Hello
GTK+ 3.0.9 is now available for download at:
ftp://ftp.gtk.org/pub/gtk/3.0/
http://download.gnome.org/sources/gtk+/3.0/
99b6327238f4fe22d89faae7a6b48fdd916ddd30183344a3b9008a2f623e2a02 gtk
+-3.0.9.tar.gz
88a9dda6f2a23155ac3d7aca6b414ca3b55e2817b46bcc87733f1a407e16678c gtk
+-3.0.9.tar.bz2