FlipTest - aleslab/Psychtoolbox-3-aleslab-fork GitHub Wiki

FlipTest

FlipTest times and plots the intervals between flips of the front and
back display buffers in a tight loop. Flips should occur at the video
frame period. Result of lipTest are a test of Priority's ability to
gurantee time to MATLAB for real-time displays.

On OS X, the Screen subfunction 'Flip' replaces 'WaitBlanking' as a means
of sycnrhonizing updates of video memory with the vertical retrace of your
monitor. This prevents vertical shearing of displays.

Onscreen windows in OS X are double buffered, having two surfaces:
front and back. The front surface is memory from which video DACs read
and is displayed on your montitor. The back surface is video memory to
which rendering commands draw.

A call to Screen 'Flip' delays until the next vertical retrace, then
instantaneously interchanges front and back video surfaces, and then
returns.