[Intel-gfx] [RFC] DRI2 swapbuffers (yes yet again)

[Jesse Barnes]

On Mon, 04 May 2009 19:14:29 -0700
Ian Romanick <idr at freedesktop.org> wrote:

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> Jesse Barnes wrote:
> > On Mon, 04 May 2009 14:45:07 -0700
> > Ian Romanick <idr at freedesktop.org> wrote:
> > 
> >> There's a problem in dri2SwapBuffers.  If a new libGL is used with
> >> an old driver, psc->dri2->setBuffers won't be set, right?
> > 
> > Yes.  I should probably add an #ifdef for that like ->flush has.
> 
> No, I mean what happens you if you build a driver from, say,
> mesa_7_4_branch and use it with libGL that has your patches applied.
> The compile-time check won't cut it.

Oh runtime mixing too... is that common?

> >> Also, should there be a mechanism for the 3D driver to force swap
> >> buffers to be implemented with a copy?
> > 
> > Hm, well the 2D driver can easily force it by not implementing a
> > swapbuffers function or by returning NULL, but I guess allowing the
> > 3D driver to force it would be ok to.  Could probably just check for
> > ->setbuffers?  Or maybe add a way for the driver to set the
> > swapAvailable flag...
> 
> Having this ability would allow us to advertise some fbconfigs with
> GLX_SWAP_METHOD_OML = GLX_SWAP_COPY_OML.  We obviously don't have any
> apps that use that today, but I can think of a couple that should. :)

Yeah, ok.

-- 
Jesse Barnes, Intel Open Source Technology Center