Hello,
I am new to gtkmm too, and i understand how you feel with documentation,
but i am used to it now, its not so bad. My only reference is the API eg
http://library.gnome.org/devel/gtkmm/unstable/namespaceGtk.html for Gtk.
I haven't done what you need to accomplish but i looked up
$image.signal_connect('expose_event') do
if $rgb == nil || $rgb.length != $iwidth*$iheight*3
puts 'rgb buffer is null or wrong length'
else
Gdk::RGB.draw_rgb_image($image.window,
$image.style.fg_gc($image.state),
0, 0, $iwidth, $iheight,
