Re: [Qemu-devel] [PATCH] opengl rendering in the sdl window

[Paul Brook]

On Sunday 07 September 2008, Samuel Thibault wrote:
> Paul Brook, le Sun 07 Sep 2008 15:36:51 +0100, a écrit :
> > > Ideally, once switched to fullscreen you could just let the guest
> > > directly write to the actual video memory (particularly interesting for
> > > Xen and KVM).
> >
> > You really don't want to have the guest writing directly to host video
> > ram. Video ram tends to be high-latency, so you want to write to regular
> > memory, then use a wide block transfer or DMA to copy to video ram.
>
> How often?  

You probably want to sync the updates to the vertical refresh. Updating more 
often than that is pointless.

> Which part(s) of the framebuffer? 

Whichever parts have changed.

Paul