Arrington Eye tracker

[Billy501]

Dear Experts

I'm wondering if anyone can clarify the data that the Arrington Plug-in is picking up in Vizard. I'm using the code below and I get three outputs which I presumes were xposition yposition and velocity (although I can seem to find any confirmation for this) - however these values don't seem to match is being shown in viewpoint. e.g I get

[0.44207999110221863, 0.4781699776649475, 0.0] in vizard

and Viewpoint is showing ~3 and 4 for x and y positions.

Thank you all for you time.


from ctypes import * # eyetrackka
import os

import sys
sys.path.append('C:/ViewPoint 2.9.2.5')
sys.path.append('C:/Program Files (x86)/WorldViz/Vizard4/plug-ins')

vpxDll = 'C:\ViewPoint 2.9.2.5\VPX_InterApp.dll'

if ( not os.access(vpxDll,os.F_OK) ):
print("WARNING: Invalid vpxDll path")

cdll.LoadLibrary( vpxDll )
vpx = CDLL( vpxDll )

#Create arrington extension
arrington = viz.add('arrington.dle')
#Connect to eye tracker
tracker = arrington.addEyeTracker()
#Print smoothed gaze position (default)
print tracker.getPosition()

[Jeff]

The 3 outputs are x,y,z although this tracker does not provide z data so the last value is 0. The gaze position is normalized from 0-1, relative to the lower left corner of the screen.