What about using the same method for fading as the gksu package does? When showing the gksudo dialog, the fading is smooth enough and the colours of the background image are ok.
-- fadeout effect on displaying the logout dialog box looks bad https://launchpad.net/bugs/39371 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
