[SDL] Re: Re: Re: extension for 2D with DRI

Martin Donlon akawaka at csn.ul.ie
Fri Apr 14 01:55:36 PDT 2000


Well if we're talking about normal audio/video playback then most of the
time they just don't wait for vsync. Windows media player certainly
doesn't and neither do most cutscenes in games.
It's not that big an issue really.

On Thu, 13 Apr 2000, Dan Maas wrote:

> > Do you want exactly 30fps, or a multiple (or short fraction) of the frame
> > rate of your monitor? In the first case you have to resample your movie,
> > either by doing very expensive interpolation, or be cheap and just
> > duplicate a frame here and there.
> 
> Ah, I was ignoring the refresh granularity problem. To get (approx) 30fps
> playback on a 100Hz monitor, I guess I'd need to alternate between holding
> each video frame for 3 and 4 retraces.
> 
> Which makes me even more curious how some Win32 apps seem to be able to do a
> good job without any direct control over the hardware. I suppose if the blit
> happens fast enough, and the OS has a low latency timer, you could "average"
> 30fps by sleeping for 33 msec; then the new frame would go out on the next
> retrace, whenever that happens to be.
> 
> Heh, wish I had a super-high-speed camera to see what really happens =)
> 
> Thanks for the insight,
> Dan
> 

Long live the confused,
                  Akawaka.
--
Bother, said Pooh as the Ewoks stole his honey pot.




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