getPredictedPresentationTime
Gets the predicted time at which this frame will be displayed.
Although no predicted time may be available, if one is available, it will be available while the frame is being generated, in contrast to method@Gdk.FrameTimings.get_presentation_time, which is only available after the frame has been presented.
In general, if you are simply animating, you should use method@Gdk.FrameClock.get_frame_time rather than this function, but this function is useful for applications that want exact control over latency. For example, a movie player may want this information for Audio/Video synchronization.
Return
The predicted time at which the frame will be presented, in the timescale of g_get_monotonic_time(), or 0 if no predicted presentation time is available.