Question Calculate how much time I spent looking at an object

So, the main idea is that I want to calculate dwell in my project. For that, I need to know the time when the player starts looking at an object and when he stopped looking at it, and calculate the difference. I am currently using the Raycasts approach, but I don't know how to specify "when you start looking" and "when you stop looking" since Raycast and RaycastHit are done in the Update method. Any idea on how to do this?

 

Go and check out this code I wrote over here:
https://forum.unity.com/threads/how...or-highlight-capability.1085438/#post-6995054
(read the follow up posts as well)

It deals with tracking a hover/gaze event.

With it you now have a 'OnCursorEnter' and 'OnCursorExit' event which you can then grab the timstamp at start and stop and track that.

 

Hey, sorry for only answering now, but I saw your solution yesterday and got a little overwhelmed by it. However, after taking a closer look at it, I have implemented a similar solution and it is working perfectly. Thanks a lot!

 

Good thing you've found a solution,
I would like to add another one:

if you specifically need to check if it's within screen boundaries, Unity has functions called onBecomeVisible and onBecomeInvisible. With this you could make something like:

Code (CSharp):

1. bool isTiming;
2.     float timer;
3.  
4.     public void OnBecameInvisible()
5.     {
6.         isTiming = false;
7.         //do stuff with timer value
8.     }
9.  
10.     public void OnBecameVisible()
11.     {
12.         timer = 0;
13.         isTiming = true;
14.     }
15.  
16.     private void Update()
17.     {
18.         if(isTiming)
19.         {
20.             timer += Time.deltaTime;
21.         }
22.     }

Edit: if your object is casting shadows in camera view it will still count as visible as to render those shadows. Something to keep in mind ^^