[cairo] xlib bug, with testcase
Antoine Azar
cairo at antoineazar.com
Wed May 28 11:25:34 PDT 2008
Hey Vlad,
There are rendering problems on Win32 too. I traced it, and the bug seems to
be coming from the fbCompositeSrc_x888xnx8888mmx function.
If you comment out this loop, it all works fine:
while (w >= 16)
{
__m64 vd0 = *(__m64 *)(dst + 0);
__m64 vd1 = *(__m64 *)(dst + 2);
......
*(__m64 *)(dst + 14) = vd7;
w -= 16;
dst += 16;
src += 16;
}
That's a temporary fix, I have no idea what the problem inside this loop
might be, maybe Fred can shed some light.
I'm attaching my resulting images, with and without MMX, and opaque and
non-opaque. The non-opaque ones are fine because we're calling a much
simpler code path, although the MMX version still gives a different result
from the non-MMX one.
Best,
Antoine
> -----Original Message-----
> From: cairo-bounces at cairographics.org
> [mailto:cairo-bounces at cairographics.org] On Behalf Of
> Vladimir Vukicevic
> Sent: Tuesday, May 27, 2008 7:51 PM
> To: cairo at cairographics.org
> Subject: [cairo] xlib bug, with testcase
>
>
> Howdy,
>
> This showed up as https://bugzilla.mozilla.org/show_bug.cgi?id=433917
> -- it seems to happen on linux and win32, though I haven't
> tried reproducing it on win32. The attached testcase shows
> the problem; I've also attached the ref rendering from the
> image backend. If the first paint_with_alpha has an alpha
> value less than 1.0, then..
> strange things happen, I'm not even sure exactly what. I'll
> try to figure out a regression range in the next few days,
> though if someone wants to beat me to it, please feel free :)
>
> - Vlad
>
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: double-alpha-image-argb32-25-out-MMX-Opaque.png
Type: image/png
Size: 609 bytes
Desc: not available
Url : http://lists.cairographics.org/archives/cairo/attachments/20080528/e1ce535f/attachment.png
-------------- next part --------------
A non-text attachment was scrubbed...
Name: double-alpha-image-argb32-25-out-NON-MMX-0.99.png
Type: image/png
Size: 596 bytes
Desc: not available
Url : http://lists.cairographics.org/archives/cairo/attachments/20080528/e1ce535f/attachment-0001.png
-------------- next part --------------
A non-text attachment was scrubbed...
Name: double-alpha-image-argb32-25-out-NON-MMX-Opaque.png
Type: image/png
Size: 593 bytes
Desc: not available
Url : http://lists.cairographics.org/archives/cairo/attachments/20080528/e1ce535f/attachment-0002.png
-------------- next part --------------
A non-text attachment was scrubbed...
Name: double-alpha-image-argb32-25-out-MMX-0.99.png
Type: image/png
Size: 644 bytes
Desc: not available
Url : http://lists.cairographics.org/archives/cairo/attachments/20080528/e1ce535f/attachment-0003.png
More information about the cairo
mailing list