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Data Fields

Floating-point sample. More...

Data Fields

UINT32 time
 
INT16 type
 
UINT16 flags
 
float px [2]
 
float py [2]
 
float hx [2]
 
float hy [2]
 
float pa [2]
 
float gx [2]
 
float gy [2]
 
float rx
 
float ry
 
UINT16 status
 
UINT16 input
 
UINT16 buttons
 
INT16 htype
 
INT16 hdata [8]
 

Detailed Description

Floating-point sample.

The EyeLink tracker measures eye position 250, 500, 1000 or 2000 times per second depending on the tracking mode you are working with, and computes true gaze position on the display using the head camera data. This data is stored in the EDF file, and made available through the link in as little as 3 milliseconds after a physical eye movement. Samples can be read from the link by eyelink_get_float_data() or eyelink_newest_float_sample().

If sample rate is 2000hz, two samples with same time stamp possible. If SAMPLE_ADD_OFFSET is set on the flags, add .5 ms to get the real time. Convenient FLOAT_TIME can also be used.

Field Documentation

UINT16 buttons

button state & changes

UINT16 flags

flags to indicate contents

float gx[2]

screen gaze x

float gy[2]

screen gaze y

INT16 hdata[8]

head-tracker data (not prescaled)

INT16 htype

head-tracker data type (0=none)

float hx[2]

headref x

float hy[2]

headref y

UINT16 input

extra (input word)

float pa[2]

pupil size or area

float px[2]

pupil x

float py[2]

pupil y

float rx

screen pixels per degree

float ry

screen pixels per degree

UINT16 status

tracker status flags

UINT32 time

time of sample

INT16 type

always SAMPLE_TYPE


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