[Xorg-driver-geode] Glyph rendering

[Michel Dänzer]

On Don, 2010-07-15 at 19:15 +0300, Mart Raudsepp wrote: 
> Hello,
> 
> On N, 2010-07-15 at 17:59 +0200, Michel Dänzer wrote:
> > On Don, 2010-07-15 at 14:13 +0300, Mart Raudsepp wrote: 
> > > On N, 2010-07-15 at 17:35 +0800, Huang, FrankR wrote:
> > > > Jonathan,
> > > > 
> > > > 	That's Mart's findings. I am not sure if he got it from debug or from code.
> > > > 	From my debug, only three rendering requests for "x11perf -aa10text" are met in lx_check_composite. That three requests are still:
> > > > 	1)Op:PictOpAdd, Src:PICT_a8r8g8b8 Mask:0 Dest:PICT_a8
> > > 
> > > 
> > > I got it from code and Michel. The source is just a pointer at the code
> > > I was looking at, and I didn't track that all the way down to its
> > > creation, as Michel said that source should commonly be PICT_a8 there.
> > > 
> > > The first checks destination is definitely PICT_a8 on first try.
> > > 
> > > The source to CheckComposite call comes from exaGlyphs second argument,
> > > which seems to be the src PICTURE passed from CompositeGlyphs{8,16,32}.
> > > This appears to be the 1x1 pixel with repeat set solid color...
> > > Why would we try to PictOpAdd that solid color to a PICT_a8 glyph alpha
> > > masks cache to decide if glyph mask copy to glyph cache is possible?
> > > Later the PictOpAdd operation is done with buffer->mask as the source
> > > instead..
> > > 
> > > Is my analysis correct and there's a bug like that in Xserver commit
> > > 346e7152?
> > 
> > Yeah. :( Probably best just to revert that commit, given it was intended
> > to help you guys but failed quite spectacularly at that...
> 
> Probably. Would probably take quite should reshuffling otherwise to work
> as intended, as the buffer pointer is gotten much later on.
> 
> 
> But this means we'll have to add Src:PICT_a8r8g8b8 Mask:0 Dest:PICT_a8
> PictOpAdd acceleration support still at rather high priority to be fast
> in existing out-the-door xorg-server-1.6/1.7/1.8 releases.

Actually, you just need to 'accept' this case in the CheckComposite
hook, you can still reject it in PrepareComposite.


-- 
Earthling Michel Dänzer           |                http://www.vmware.com
Libre software enthusiast         |          Debian, X and DRI developer