Problem in miClipPictureSrc?
sandmann at daimi.au.dk
Fri Oct 2 07:07:31 PDT 2009
"Kim Woelders" <kim at woelders.dk> writes:
> Commit 128cd03eecacc6d5c5903d59a11966dcf3697bf1 causes trouble with
> clip regions in the e16 WM composite manager (e.g. during fade-out).
This marks the second recorded use of source clipping in the history
of the Render extension.
> The problems are fixed by attached patch. Not sure if this is the
> proper solution though...
The intent of this code is to shift the client clip into destination
coordinates, then clip against it. Translating by clipOrigin.x/y
converts from region coordinates to source coordinates, and dx/dy is
supposed to bring it into destination coordinates.
The problem with the commit I think is that I was thinking of dx/dy as
the amount the destination is shifted, when it actually is how much
the source is shifted.
If so, the real fix would be:
> @@ -318,14 +318,14 @@ miClipPictureSrc (RegionPtr pRegion,
> Bool result;
> pixman_region_translate ( pPicture->clientClip,
> - pPicture->clipOrigin.x - dx,
> - pPicture->clipOrigin.y - dy);
> + dx - pPicture->clipOrigin.x,
> + dy - pPicture->clipOrigin.y);
+ pPicture->clipOrigin.x + dx,
+ pPicture->clipOrigin.y + dy,
and a similar correction after the intersection.
I'd be interested in whether the same bug exists with the vesa driver
(or another unaccelerated one).
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