[PATCH] Re: Problem in miClipPictureSrc?

[Kim Woelders]

On Fri, 02 Oct 2009 23:32:31 +0200, Kim Woelders <kim at woelders.dk> wrote:

> On Fri, 02 Oct 2009 16:07:31 +0200, Soeren Sandmann  
> <sandmann at daimi.au.dk>
> wrote:
>
>> "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.
>>
> Yes, that works too (presumably because pPicture->clipOrigin.x/y always =
> 0 in my case).
> New patch attached.
>
>> I'd be interested in whether the same bug exists with the vesa driver
>> (or another unaccelerated one).
>>
> I tried the vesa driver but get only a mostly black screen.
>
... this time with patch...

/Kim
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-render-Fix-clip-region-translation-in-miClipPictureS.patch
Type: text/x-patch
Size: 0 bytes
Desc: not available
Url : http://lists.x.org/archives/xorg-devel/attachments/20091002/39d0cd8a/attachment.bin