Move GameObject with Gaze Point

[Varun Ramakrishnan]

I am currently trying to move an object with the user’s gaze point but am having trouble converting the gaze point to a world space position.

My scene setup is:
– An eye image on a canvas that follows the user’s gaze (so that the user can see what they’re looking at)
– A cube on a plane that the user is supposed to move with their eyes.

The objective is for the user to move the cube with their eye after looking at it. I change the cube’s material color once it HasGazeFocus and that works without any issues so I know that the GazeAware component and Tobii are working correctly.

    void Update()
    {
        transform.position = Camera.main.ViewportToScreenPoint(Tobii.Gaming.TobiiAPI.GetGazePoint().Viewport);
    }

The canvas image has the above in a script attached to it and moves correctly but the cube is always at the same position.

I have tried using GetGazePoint().Screen followed by camera.ScreenToWorldPoint as well as ‘GetGazePoint().Viewportfollowed bycamera.ViewportToWorldPoint` but neither of them seem to change the cube’s position.

Right now I’m moving it in 2D along the XY plane so I fix the z-coordinate to a constant.

Any pointers on how I could make the cube move with the eye would be appreciated.

[Grant [Tobii]]

Hi @vramakrishnan, did you check the values of the gaze point as reported in the sample script we produced @

https://developer.tobii.com/pc-gaming/unity-sdk/scripting-api/#tobiiapigetgazepoint

using Unity.Engine;
using Tobii.Gaming;

public class ExampleClass : MonoBehaviour
{
    void Update()
    {
        GazePoint gazePoint = TobiiAPI.GetGazePoint();
        if (gazePoint.IsRecent()) // Use IsValid property instead to process old but valid data
        {
            // Note: Values can be negative if the user looks outside the game view.
            print("Gaze point on Screen (X,Y): " + gazePoint.Screen.x + ", " + gazePoint.Screen.y);
        }
    }
}

It would be an idea to see what values are being produced to see how to convert them to your own desired coordinate system.

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