[Mesa-dev] [PATCH 04/10] intel: Define enum intel_dri2_has_hiz

[Chad Versace]

On Tue, 07 Jun 2011 10:33:44 -0700, Eric Anholt <eric at anholt.net> wrote:
> On Sat,  4 Jun 2011 17:45:37 -0700, Chad Versace <chad at chad-versace.us> wrote:
> > ... which indicates if the X driver supports DRI2BufferHiz and
> > DRI2BufferStencil.
> > 
> > I'm placing this in its own commit due to the large comment block.
> > 
> > CC: Eric Anholt <eric at anholt.net>
> > CC: Ian Romanick <idr at freedesktop.org>
> > CC: Kenneth Graunke <kenneth at whitecape.org>
> > CC: Kristian Høgsberg <krh at bitplanet.net>
> > Signed-off-by: Chad Versace <chad at chad-versace.us>
> > ---
> >  src/mesa/drivers/dri/intel/intel_screen.h |   54 +++++++++++++++++++++++++++++
> >  1 files changed, 54 insertions(+), 0 deletions(-)
> > 
> > diff --git a/src/mesa/drivers/dri/intel/intel_screen.h b/src/mesa/drivers/dri/intel/intel_screen.h
> > index 4613c98..d4add6a 100644
> > --- a/src/mesa/drivers/dri/intel/intel_screen.h
> > +++ b/src/mesa/drivers/dri/intel/intel_screen.h
> > @@ -34,6 +34,60 @@
> >  #include "i915_drm.h"
> >  #include "xmlconfig.h"
> >  
> > +/**
> > + * \brief Does the X driver support DRI2BufferHiz and DRI2BufferStencil?
> > + *
> > + * The DRI2 protocol does not allow us to query the X driver's version nor
> > + * query for a list of buffer formats that the driver supports. So, to
> > + * determine if the X driver supports DRI2BufferHiz and DRI2BufferStencil we
> > + * must resort to a handshake.
> > + *
> > + * If the hardware lacks support for separate stencil (and consequently, lacks
> > + * support for hiz also), then the X driver's separate stencil and hiz support
> > + * is irrelevant and the handshake never occurs.
> > + *
> > + * Complications
> > + * -------------
> > + * The handshake is complicated by a bug in the current driver version. Even
> > + * though the driver currently does not support requests for DRI2BufferHiz or
> > + * DRI2BufferStencil, if requested one it still allocates and returns one. The
> > + * returned buffer, however, is incorrectly X tiled.
> 
> I would word this in the past tense.

How about this?
 + * Complications
 + * -------------
 + * The handshake is complicated by a bug in xf86-video-intel 2.14. Even though
 + * that version of the X driver did not supppot requests for
 + * DRI2BufferHiz or DRI2BufferStencil, if requested one it still allocated and
 + * returned one. The returned buffer, however, was incorrectly X tiled.

----
Chad Versace