[cairo] Stange alpha channel problem.

Paul Giblock drfaygo at gmail.com
Wed Jun 14 06:29:59 PDT 2006


Doh! I sent the picture from my Desktop (working) system. Here is the
png from my laptop (broken) system.  I need to return my laptop to the
factory to replace some plastic on it, so I'd like to try and get this
testing done so I can send the laptop.

Thanks,
Paul

On 6/14/06, Paul Giblock <drfaygo at gmail.com> wrote:
> 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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