[Cairo] PNG backend for cairo?

[Carl Worth]

[quoting reordered to maintain better flow]

On Nov 15, Abraham Egnor wrote:
 > David Morse <svref at yahoo.com> writes:
 > >
 > >./configure --with-png=yes ?
 >
 > ...which would then have to propagate to all of the language bindings, and
 > anything else that wants to be backend-agnostic, and...

We can certainly provide macros in cairo.h to advertise the set of
backends that are available.

-Carl