[cairo] set_source_rgb vs set_source_rgba [Performance]

[Ian Britten]

Hi all,
When drawing solid colours (Alpha=1.0), is there any performance
benefit to using set_source_rgb() as opposed to set_source_rgba()?

I'm wondering whether to add the complexity to my code to
distinguish the two cases and make the appropriate calls, or
whether simply calling set_source_rgba() all the time will
automatically fall back to same behaviour?
[ Obviously, rendering speed is a concern, and I'll add the
complexity to our code, if there's a benefit ]

Thanks!
Ian