>Psychtoolbox>PsychGLImageProcessing

rval = kPsychSkipWaitForFlipOnce

Return a flag that you can pass as part of the flipFlags for a call to
Screen(‘Hookfunction’, windowPtr, ‘SetOneshotFlipFlags’, flipFlags);

This flag will skip the wait until the ‘when’ deadline during execution
of the next Screen(‘Flip’, window, when) operation. It is useful if an
external display output client/provider, e.g., a VR headset, is active
and attached to an onscreen window, and the visual stimulus onset
scheduling should be performed by the dedicated display output provider,
e.g., if our standard scheduling won’t do for such a special purpose device.
The imaging pipeline provides the special variable “IMAGINGPIPE_FLIPTWHEN”
which can be used when calling Octave/Matlab runtime function from within
an imaging pipeline processing chain to pass the ‘when’ time to the runtime
function, e.g., for scheduling.