[cairo] regression in text rendering when not using Render xlib

[Frederic Crozat]

Hi,

our install guys are often using Xnest to test Mandriva installer in a
chroot and they reported me that glyph rendering has regressed since we
switched to cairo 1.3.x in cooker (see bug
http://qa.mandriva.com/show_bug.cgi?id=28317 ).

I try to duplicate similar problem with a smaller testcase and I was
able to have strange rendering when doing the following :
Xnest :1 & (or Xephyr -extension RENDER :1 ).
DISPLAY=:1 zenity --about 

and check Zenity text : it has some strange colors in it (looks like bad
subpixel hinting, but subpixel hinting isn't enabled in Xnest).

Switching to Xephyr with RENDER enabled hides this problem.

I've attached two screenshots.

Test are done with freetype 2.3.1 (no patch, no bytecode interpreter
enabled) but also with 2.2.1+several CVS patches, DejaVu font 2.15
(already present with 2.12).

If I revert to cairo 1.2.x, problem disappear, with same version of
pango.

-- 
Frederic Crozat <fcrozat at mandriva.com>
Mandriva
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