Gaze velocity calculation

[mrk88]

Hello

I am trying to calculate instant gaze velocity, using gaze position.

I found out that pupil_position_on_sensor does not indicate the true gaze position. Therefore I have to use gaze direction vector, which is normalized.

- How can I calculate instantaneous gaze velocity based on normalized Gaze Direction Vector?

- Do I need to denormalize it? How?

Thank you so much for nay ideas/help!

@Corvus @Daniel_Y

[mrk88]

The problem with denormalizing is that I only have Height and Width of the display for each eye, but the Gaze Direction Vector is 3d. How to map the Z coordinate to the display resolution?

[Daniel_Y]

You could use gaze vector to calculate the velocity vector. FYR, https://stackoverflow.com/questions/9447806/finding-3d-velocity-vector

 

[mrk88]

 

9 hours ago, Daniel_Y said:

You could use gaze vector to calculate the velocity vector. FYR, https://stackoverflow.com/questions/9447806/finding-3d-velocity-vector

 

Thanks, but my question is how to calculate gaze position from gaze direction vector.

For velocity calculation I need to have start and end gaze position.

[Daniel_Y]

13 hours ago, mrk88 said:

 

Thanks, but my question is how to calculate gaze position from gaze direction vector.

For velocity calculation I need to have start and end gaze position.

You could refer to Focus sample enclosed in SDK to know what object you are looking at in VR 3D world from gaze vector.