[cairo] Cairo 1.10 rendering text to transparent image surface

[Geoff Youngs]

Hi,

I've found that rendering light coloured (it's not so visible with
black) text to an image surface with an (at least partially)
transparent background results in unwanted artefacts where I'd expect
to see smooth anti-aliasing.

Example code was compiled with:
gcc `pkg-config --cflags --libs pango cairo pangocairo` -o
cairo-text-on-transparency cairo-text-on-transparency.c

I'm running cairo 1.10.0, pixman 0.19.7+git20101025.1c23142e and pango
1.28.0, albeit all from ubuntu packages.

I couldn't find any bugs in Bugzilla that seemed relevant - is this
just a facet of my environment or is there a bug/regression here?

Thanks in advance,


Geoff.
-- 
Geoff Youngs
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