How do I wait for vertical retrace?
samuel.thibault at ens-lyon.org
Thu May 8 02:43:48 PDT 2008
Barry Scott, le Thu 08 May 2008 10:36:37 +0100, a écrit :
> Glynn Clements wrote:
> > Carsten Haitzler (The Rasterman) wrote:
> >> wonderful... in theory. in practice a lot of hardware ONLY provides a vblank
> >> interrupt. no interrupt for line X. :(
> > You don't need the signal to come directly from the video hardware. If
> > you know your clock frequencies, you can use the OS' timers; you just
> > need to phase-lock to vsync to prevent drift.
> Without the signal from the hardware you cannot avoid tearing. We tried
> OS timer to get smooth animation and it does not work very well on
Maybe that's because your linux had a fixed-frequency RTC set to 100Hz ?
(thus not precise enough).
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