Ray casting with Hololens eye gaze

Hello everyone,
Might be my question is silly but I would really appreciate it if you guys help me.
I have run a raycasting example with on-screen points(mouse pointer) that work perfectly fine I want to explore it with HoloLens eye gaze data.
HoloLens Giving me EYE GAZE 3D directional vector.
How could I pass a ray from cam position to giving position in the space?

@sgold

Once you have the origin position (the camera position) and a direction vector (the eye gaze) you can just use the same ray casting technique to find where the user is looking in the scene.

I don’t understand the question. Sorry!