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Get Focussed Vector

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I am trying to get the focus of the focussed point. Therefore I have multiple ideas:


1) Calculate the intersection of the line consisting out of data.verbose_data.left.gaze_origin_mm and data.verbose_data.left.gaze_direction_normalized (left eye line) as well as  data.verbose_data.right.gaze_origin_mm and data.verbose_data.right.gaze_direction_normalized (right eye line). Unfortunately, this doesn't return an intersection point because they do not cross each other.


2) I saw that Tobii XR SDK offers a function "GetEyeTrackingData" (https://vr.tobii.com/sdk/develop/unity/documentation/usage-examples/). Unfortunately the class TobiiXR has no function GetEyeTrackingData and therefore I am not able to use it.


Does anyone has any idea/ideas?

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Did you see the Focus example (dart boards)? Check out the Focus call back on the dartboard object's script as well as the script on it's parent.

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@Dario Yes I already looked into this example. But within this example, I have to "define" which objects can be focussed.

But I just want to get the point of focus, indepent if a person focussed an object or just watch into the air.

Therefore I thought about the following idea:

I can receive the eye data via SRanipal_Eye_API.GetEyeData(ref data) and therefore have the eye data of the left, right eyes as well as the combined data.

So in the next step I am calculating the focussed point by calculating the minimal distance between the two lines of the left and right eye. If the minimal distance is 0, they have an intersection point:

lineLeft= gazeOrigin_left + l * normalizedGazeDirectionVector_left

lineRight= gazeOrigin_right + k * normalizedGazeDirectionVector_right



  • gazeOrigin_left == data.verbose_data.left.gaze_origin_mm
  • normalizedGazeDirectionVector_left_left ==  data.verbose_data.left.gaze_direction_normalized
  • gazeOrigin_right == data.verbose_data.right.gaze_origin_mm
  • normalizedGazeDirectionVector_right ==  data.verbose_data.right.gaze_direction_normalized


Unfortunately the two lines do not have an intersection point, but I do not understand why.


Anyone has any ideas why there is no intersection point? 


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