ShowPlay Reference Manual, Chapter 3 (ControlVariables): eye_flag
Eye_flag is an integer variable that Showplay uses to control whether and how to collect eyetracking data. The variable is used as a bit flag, in which each binary bit controls a different option. Combine different options by adding bit values. If eye_flag is 0, all eyetracking features are turned off; this is the default setting.
The bit values (specified in octal) for eye_flag options are:
1 - monitor eye position X/Y values sent from the eyetracker 2 - monitor pupil size X/Y values sent from the eyetracker 4 - 1000o -