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Data Fields
DSAMPLE2 Struct Reference

Floating-point sample with floating point time. More...

Data Fields

double 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]
 
float eyeInHeadX [3]
 
float eyeInHeadY [3]
 
UINT32 headMarkerFlags
 
float headRotation [3]
 
float headPosition [3]
 
float headInSpaceX
 
float headInSpaceY
 
float unused_headInSpaceX [2]
 
float unused_headInSpaceY [2]
 
float hrgx
 
float hrgy
 
float ergx
 
float ergy
 
float ex [2]
 
float ey [2]
 
float emajor [2]
 
float eminor [2]
 
float eangle [2]
 

Detailed Description

Floating-point sample with floating point time.

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_double_data() or eyelink_newest_double_sample().

The difference between DSAMPLE and DSAMPEL2 is, the DSAMPEL2 has extra data specifically for EyeLink 3. The extra data defaults to 0 or MISSING if used with a preceding model of camera.

Field Documentation

UINT16 buttons

button state & changes

float eangle[2]

pupil ellipse angle (pupil_ellipse_angle[2])

float emajor[2]

pupil ellipse minor axis (ef.minor)

float eminor[2]

pupil ellipse major axis (ef.major)

float ergx

resolution for eyeInHead

float ergy

resolution for eyeInHead

float ex[2]

pupil ellipse x

float ey[2]

pupil ellipse y

float eyeInHeadX[3]

eye alone gaze x. Uncompensated head gaze. left right, cyclopean

float eyeInHeadY[3]

eye alone gaze y. Uncompensated head gaze. left right, cyclopean

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)

float headInSpaceX

Head in space is the head movement contribution to on screen gaze. It is calculated by transforming the central fixation cyclopean eye-gaze vector by the head movement. The monocular central fixation gaze is a vector starting at the midpoint between the eyes and ending at the central calibration point. Note when in monocular mode this is taken based on the selected eye-gaze during the first calibration point (rather than cyclopean).

float headInSpaceY

Head in space is the head movement contribution to on screen gaze. It is calculated by transforming the central fixation cyclopean eye-gaze vector by the head movement. The monocular central fixation gaze is a vector starting at the midpoint between the eyes and ending at the central calibration point. Note when in monocular mode this is taken based on the selected eye-gaze during the first calibration point (rather than cyclopean).

UINT32 headMarkerFlags

Head marker flags provides marker warnings

float headPosition[3]

Head Position value of X at the index of 0, Y at the index of 1 and Z at the index of Z

float headRotation[3]

Head rotation value of X at the index of 0, Y at the index of 1 and Z at the index of Z

float hrgx

resolution for headInSpace (cyclopean only)

float hrgy

resolution for headInSpace

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

double time

time of sample

INT16 type

always SAMPLE_TYPE

float unused_headInSpaceX[2]

head gaze x. one from the prespective of left eye (0), next prospective of right eye (1) the third one is cyclopean

float unused_headInSpaceY[2]

head gaze y. one from the prespective of left eye (0), next prospective of right eye (1) the third one is cyclopean


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