[cairo] On multiplying alpha

[Behdad Esfahbod]

I wrote some code about how to go from premultiplied alpha to multiplied
alpha formats.  Thought people here may be interested to review:

  http://bugzilla.gnome.org/show_bug.cgi?id=513812

Cheers,
-- 
behdad
http://behdad.org/

"Those who would give up Essential Liberty to purchase a little
 Temporary Safety, deserve neither Liberty nor Safety."
        -- Benjamin Franklin, 1759