Drawing an insensitive widget

[ax487 <ax487 gmx de>]

Hello all,

I have the following problem: I have a widget with a custom drawing
routine which is triggered by the widgets "expose-event". I just obtain
a cairo_t* and use it to draw on the widget. However, at some point in
time the widget might be insensitive. Of course the widget should still
be drawn. However, I would like to know how I can appropriately achieve
the "greyed out" effect. Any ideas for a portable, clean solution?

ax487