Is it possible to access eye tracking data like pupil diameter on hololens 2?

Question

Is there a way to store and view eye tracking data like the size of the users pupils or the eye motion speed?

I am currently building a hololens 2 application in unity using MRTK. Now I would like to "record", store and view eye tracking data of the user.

Answer 1

I don't believe you can get pupil diameter but it looks like you could estimate angular speed by measuring the change in gaze direction between frames:

Vector3 previousGazeDir;

// ...

Vector3 newGazeDir = CoreServices.InputSystem.EyeGazeProvider.GazeDirection;

if (previousGazeDir != Vector3.zero)
{
    float gazeAngle = Vector3.Angle(previousGazeDir, newGazeDir);

    float gazeAngularVelocity = gazeAngle/Time.deltaTime;

    // .. do stuff with gazeAngularVelocity
}

previousGazeDir = newGazeDir;

Depending on your exact use case you may want to account for changes in the direction the head is facing.