I got it, thanks! Actually, in function st_init_clear(), if I set
bypass_vs_clip_and_viewport as 0, things get better.
Another question is about the function clear_with_quad() provided by state
tracker, this function can clear color/depth buffer through a quad, but
driver's pipe->clear can also implement the operation by filling a furface,
which one is prefered?
Could you please tell me the difference between mesa/state tracker and
gallium/state tracker?
Cooper
On Tue, Aug 18, 2009 at 6:49 AM, Keith Whitwell <kei...@vmware.com> wrote:
> On Tue, 2009-08-18 at 05:25 -0700, Cooper Yuan wrote:
> > Hi,
> >
> > Does bypass_vs_clip_and_viewport influence vertex fetch?
> > I thought vertex transform engine is behind vertex shader, that means,
> > bypass_vs_clip_and_viewport will not impact vertex fetch.
> >
> > But when I debug glClear issue on r500 gallium driver, if driver
> > disable VTE, the color data can't be fetched (position is correct),
> > enabled VTE can fetch color data successfully.
> >
> > Could anyone give me clues?
>
> All this flag means is that the state tracker is sending you
> pre-transfomed (ie window-space) vertex positions. If it sends you
> vertex x,y == 100,300 then one corner of your triangle is at that pixel
> coordinate. It's basically the same case as if you've used the draw
> module to do software transformation within the driver.
>
> That said, I think we remove the remaining usage of this functionality
> from the Mesa state tracker - it's a serious corner case for the
> open-source drivers.
>
> Keith
>
>
>
>
------------------------------------------------------------------------------
Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day
trial. Simplify your report design, integration and deployment - and focus on
what you do best, core application coding. Discover what's new with
Crystal Reports now. http://p.sf.net/sfu/bobj-july
_______________________________________________
Mesa3d-dev mailing list
Mesa3d-dev@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/mesa3d-dev
