Re: [Qemu-devel] [PATCH] Add QEMU DirectFB display driver

[Anthony Liguori]

On 05/17/2010 10:09 AM, Julian Pidancet wrote:
> On 05/17/2010 02:30 PM, Anthony Liguori wrote:
>    
> > On 05/15/2010 08:10 PM, Paul Brook wrote:
> >      
> > > > The other solution would be to use the DirectFB driver for SDL which
> > > > would allow to do slightly the same as this patch. But that would mean
> > > > having to deal with an additional layer in the graphical stack, which is
> > > > not exactly what one wants from a performance or a complexity point of
> > > > view.
> > > >
> > > >          
> > > I don't buy your complexity argument.  Doesn't DirectFB-via-SDL already work?
> > > If not why not? I'm pretty sure fixing that would be way simpler than adding a
> > > whole new output backend.
> > >
> > >        
> > Yeah, I don't buy it either.  I think performance data is probably the
> > only way to justify this and I'm sceptical that if there is a
> > performance advantage that it wouldn't be possible to just fix SDL's
> > DirectFB support.
> >
> >      
> I don't think wether fixing or not SDL is the debate here, the question would 
> be more wether or not we want to add a lightweight display driver to qemu. 
> Also, I think a DirectFB driver is fairly easy to maintain.
>    

Generally speaking, adding DirectFB doesn't seem like a net win to me.  
We still have to maintain SDL so now there's just more code to 
maintain.  I'd rather there be one way of doing things that everybody 
focused on making work best than have two ways to do the same thing (if 
at all possible).

Regards,

Anthony Liguori

> I will get some performance data as soon as I have some time.
>
> By the way, sorry for the patch reposts, it seems that my smtp server had quite 
> some trouble to relay messages last week.
>
>