Hunting a specific signal... (Map event?)

[Douglas Ian Linder <linderdi cs curtin edu au>]

I'm hunting a signal but I can't quite find the one I'm looking for:

What I want is the signal to be generated after a widget has been
displayed and thus has had it's initial size realised. I've tried
the map-event, but that turns up too soon.

Any other suggestions?

The purpose: A gtk-image gets rendered from pixel data; the size of
the image widget determines what sub section of the pixel data is 
rendered, but the widget size (initially) depends on the layout...

cheers,
Doug.