Can you give me an example of usage please?

Ty very much

I don't need eye tracking, like they did that highlight effect when you look at a 3D object, I just want the possibility to add different effects

I found my answer here: https://developer.apple.com/documentation/visionOS/tracking-points-in-world-space

I solved the problem, the flicker was caused by the fact that I updated dynamic the tab view pages so now I prepopulated it with a number of pages than create my cards and remove the extra ones. But thank you for your answer @Vision Pro Engineer