[cairo] Stange alpha channel problem.

Paul Giblock drfaygo at gmail.com
Wed Jun 14 06:24:21 PDT 2006


Oh ok, The problem is visible on the X Window itself, not just the
exported png file.

On 6/14/06, Vladimir Vukicevic <vladimirv at gmail.com> wrote:
> I haven't tried it -- we had a problem in mozilla where we were
> quantizing down to 16bpp in some cases and then reading back from that
> to composite, thus introducing precision errors which manifested
> themselves in the same way that you describe (painting with fully
> transparent OVER gradually darkened the image).  So I was wondering if
> it might be another instance of that type of bug, but it doesn't sound
> like it.
>
>     - Vlad
>
> On 6/13/06, Paul Giblock <drfaygo at gmail.com> wrote:
> > Vlad -
> >
> > No, according to my xorg.conf and xvinfo, my laptop is running at
> > 24bits.  What does my program during your test? I assume it runs fine?
> >
> > -Paul
> >
> > On 6/14/06, Vladimir Vukicevic <vladimirv at gmail.com> wrote:
> > > On 6/13/06, Paul Giblock <drfaygo at gmail.com> wrote:
> > > > I just tried to run this source on my desktop.  I forgot to mention a
> > > > few things:  you must add -lX11 to your compile line.  You may have to
> > > > add #include <stdlib.h> to the source.
> > > >
> > > > Finally, on my desktop there is no darkening problem. The darkening
> > > > still occurs on my laptop.  Both systems are running cairo-1.1.6.
> > >
> > > Is your laptop X server running in 16-bit color mode, and your deskop in 24/32?
> > >
> > >     - Vlad
> > >
> >
> >
>
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