Re: [Dri-devel] mach64 blend

[Leif D. <lde...@re...>]

On Tue, 28 Jan 2003, Leif Delgass wrote:

> > BTW, when particular operation is implemented in software but require some
> > on-screen content, driver copy already rendered chunk from framebuffer, pass
> > it to Mesa, then copy back?
> 
> To be honest, I don't know the gory details of the Mesa software 
> rasterizer yet, but any primitives needing a texture application that 
> can't be done in hardware would be completely software rendered and 
> written to the framebuffer, I think.

I'm not sure I actually answered your question here.  The Mesa software
rasterizer would have to read from the frambuffer, apply any blending
function, logic op, etc. and then write the result back to the
framebuffer.  The driver supplies callbacks to read and write spans and
pixels to and from the framebuffer, which the Mesa sw rasterizer would
call (mach64_span.c).  You can look at mach64_tris.c and mach64_vb.c to
see how the driver hooks into the Mesa pipeline.

-- 
Leif Delgass 
http://www.retinalburn.net