lack of vsync on a Lion Macbook Air

[Jonathan Peirce]

Hi there,

I've just had a report from a PsychoPy user that syncing to the frame appears not to be working for a new macbook air under Lion. Possible reasons that spring to my mind are that;
    - the intel HD 3000 doesn't support this. I've had trouble with intel chips under windows in the past, but under mac the drivers seem to have been much better, so I doubt that's the problem
    - Lion has changed in the way the cocoa call is made to set the frame syncing behaviour, or simply doesn't support vsync any more (which would be very annoying indeed!)

The way it worked on previous versions was using:
CGLSetParameter(CGLGetCurrentContext(), kCGLCPSwapInterval,&1)

That code still doesn't give an error message, on this user's macbook air, but appears to have no effect.

Has anyone else seen such issues and/or does anyone have an alternative Lion desktop available on which we could separate the two hypotheses above?

Jon

-- 
Dr. Jonathan Peirce
Nottingham Visual Neuroscience

http://www.peirce.org.uk/