Crux engine drawing problems

[Seth Nickell <snickell stanford edu>]

I've been unable to track down a drawing problem with Crux engine
('crux' module in GNOME cvs) and I was wondering if people could give me
suggestions where to keep looking. I've spent several hours on this and
haven't been able to figure out exactly what's going wrong.

The symptom is that many out-of-process components end up with black
backgrounds where the widgets don't explicitly draw something. This
happens, for example, when a GtkImage with a pixmap that has transparent
regions is used as the primary control for a panel applet, such as in
the GNOME2 volume slider applet. You can see that here: (also this
happens on the dictionary applet which is rightmost in this shot)

  http://beauty.stanford.edu/panel-black.png

This also manifests itself in the Nautilus throbber (another out of
process component):

http://beauty.stanford.edu/throbber-black.png

I'm printing all calls GTK gives to the Crux engine, but I'm just not
seeing a call to draw flat_box or whatever should be drawn there.
Suggestions as to what I might be doing wrong would be really
appreciated. I'm stumped :-)

-Seth