These commands are used to set tracker configuration. This should be done at the start of each experiment, in case the default setting were modified by a previous experiment.

Configuration: Eyes Tracked

active_eye = <LEFT or RIGHT>

Controls which eye is recorded from in monocular mode

Arguments:

LEFT or RIGHT monocular eye selection

binocular_enabled = <YES or NO>

Controls whether in monocular or binocular tracking mode .

Arguments:

YES for binocular tracking
NO for monocular tracking

Anti-Reflection Control

Remarks: EyeLink I only!!!

head_subsample_rate = <0, -1, or 4>

Can be used to disable monitor marker LEDS, or to control antireflection option.

Arguments:

0 for normal operation
4 for antireflection on
-1 to turn off markers

heuristic_filter (EyeLink I)

heuristic_filter = <ON or OFF>

Can be used to disable filtering, reduces system delay by 4 msec. NEVER TURN OFF THE FILTER WHEN ANTIREFLECTION IS TURNED ON.

Arguments:

ON enables filter (usual)
OFF disables filter

heuristic_filter (EyeLink II, EyeLink 1000, 1000 Plus, and Portable Duo)

heuristic_filter = <ON or OFF>
heuristic_filter = <linkfilter>
heuristic_filter = <linkfilter> <filefilter>

Can be used to set level of filtering on the link and analog output, and on file data. An additional delay of 1 sample is added to link or analog data for each filter level. If an argument of <on> is used, link filter level is set to 1 to match EyeLink I delays. The file filter level is not changed unless two arguments are supplied. The default file filter level is 2.

Arguments:

0 or OFF disables link filter
1 or ON sets filter to 1 (moderate filtering, 1 sample delay)
2 applies an extra level of filtering (2 sample delay).

pupil_size_diameter

pupil_size_diameter = <YES or NO>

Arguments:

YES to convert pupil area to diameter
NO to output pupil area data

simulate_head_camera

simulate_head_camera = <YES or NO> Can be used to turn off head tracking if not used. Do this before calibration

Arguments:

YES to disable head tracking
NO to enable head tracking

simulation_screen_distance

simulation_screen_distance = <mm>

Used to compute correct visual angles and velocities when head tracking not used.

Arguments:

<mm>: simulated distance from display to participant in millimeters.