Accessing a GdkPixmap?

[Constantine Vetoshev <con consela com>]

I am in the process of writing a GTK+ ray tracer that uses a
GdkPixmap off-screen buffer. This system works fine for simply
displaying generated images, but a problem arises when I need to save
the images. Two questions, therefore, arise: how do I access
individual pixels of a pixmap, and what is the byte ordering scheme
for these pixels? I tried to look for the struct definition in the
include files, but couldn't find it.

Also, I stumbled on a GtkImage class in the GTK+ reference, but I
could find no documentation on what it is and what it does. What is
it, exactly? (I'm just thinking that it might be an easier way of
implementing graphical images that live in GTK+ apps).


Regards,
Constantine Vetoshev