Quoting Antonino Daplas ([EMAIL PROTECTED]):
> On Fri, 2002-01-18 at 00:04, Adam Agnew wrote:
> > 
> > I'm surprised to see how much a Pentium2 300Mhz MMX on a Matrox G550
> > spanks my Voodoo3 3500 on a dual AMD 1800+ XP. This makes it quite obvious
> > that we're really depending heavily on hardware acceleration especially
> > for all things alpha channel :P So, two questions:
> > 1) Are there any speed ups for software based rendering that can be done
> > but have not yet been implemented? The project I'm working on depends
> > heavily on alpha channels so I'd be very interested in any software speed
> > ups we can get. and
> > 2) Are the alpha-channel hardware speed ups dependant on some kind of
> > hardware feature? I know some recent cards have made a big woopdie-doo
> > about anti-aliasing in games. Are these features DirectFB is tapping into?
> 
> I was surprised at the numbers you people posted and realized what a
> lousy chipset the i810 is :).  Still, your benchmarks for the software
> rasterizer is disproportionately slow for your system.  Maybe you have a
> bandwidth problem.  MTRR perhaps.  
> 
> Which leaves me to this question:
> 
>   For chipsets where bandwidth is actually much better than chipset
> speed, occasionally the software rasterizer is faster than the
> equivalent accel functions.  Especially for draw rect and
> draw_triangle.  To draw spanlines, directfb uses FillRect, if accel
> function is present, otherwise, the rasterizer is used.to draw a
> SpanLine.  FillRect if used to draw small number of pixels is just too
> slow for the i810, and I would prefer the software to write directly to
> the framebuffer rather than use FillRect for it.  Can I have a choice? 
> I hope I'm not asking too much.

The problem with the i810 is the ioctl for each command, maybe we can gather
commands in the buffer and flush it after a specified threshold and by calling
EngineSync.

The software is pretty fast on your machine because the video memory is the same
physical memory as the system memory on your machine.

-- 
Best regards,
  Denis Oliver Kropp

.------------------------------------------.
| DirectFB - Hardware accelerated graphics |
| http://www.directfb.org/                 |
"------------------------------------------"

           convergence integrated media GmbH


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