Raycasting for a period of time

Ive tried looking this up and i haven't found anything helpful.

Im using raycasting and I want to know if this ray has hit an object for lets say 5 or more seconds.

Whats the best way to do this?

Thanks!

 

Coroutine.

 

How exactly, if i understood the documentation correctly it is essentially a function that resumes after each frame, how would I handle the timing issue? How do I record the initial time the ray hits the object and compare that with the current time? ( I know how to do this but how do i reset the initial time after the raycast exits the object?)

 

There are multiple ways to do this.
I created a simple RayCaster class to simplify ray casting (see below).
How to use the class:

Code (CSharp):

1. private RayCaster ray;
2. private float rayHitStart = 0f;
3.  
4. void Start() {
5.     ray = new RayCaster();
6.     ray.OnRayEnter += Ray_OnEnter;
7.     ray.OnRayStay += Ray_OnStay;
8.     ray.OnRayExit += Ray_OnExit;
9.     // ray.LayerMask = RayCaster.GetLayerMask("Wall");  // OPTIONAL
10.     ray.StartTransform = startObject.transform;
11.     ray.EndTransform = endObject.transform;
12. }
13.  
14. void LateUpdate() {
15.     ray.CastRay();
16.     // ray.CastLine();  // If you want to use a Line Caster instead.
17. }
18.  
19.  
20. void Ray_OnEnter(Collider collider) {
21.     if (collider.name == "ObjectName") {
22.         rayHitStart = Time.time;
23.     }
24. }
25.  
26. void Ray_OnStay(Collider collider) {
27.     if (collider.name == "ObjectName") {
28.         if (Time.time - rayHitStart > 5f) {
29.             // Object has been hit for five seconds - do something!
30.         }
31.     }
32. }
33.  
34. void Ray_OnExit(Collider collider) {
35.     if (collider.name == "ObjectName") {
36.         rayHitStart = 0f;
37.     }
38. }

RayCaster class:

Code (CSharp):

1. using System;
2. using System.Collections;
3. using UnityEngine;
4.  
5. public class RayCaster {
6.  
7.     public Transform StartTransform;
8.     public Transform EndTransform;
9.     public Vector3 Direction;
10.     public float RayLength;
11.     public int LayerMask = 0;
12.  
13.     public event Action<Collider> OnRayEnter;
14.     public event Action<Collider> OnRayStay;
15.     public event Action<Collider> OnRayExit;
16.  
17.     Collider previous;
18.     RaycastHit hit = new RaycastHit();
19.  
20.     public bool CastRay() {
21.         Physics.Raycast(StartTransform.position, Direction, out hit, RayLength, LayerMask);
22.         ProcessCollision(hit.collider);
23.         return hit.collider != null ? true : false;
24.     }
25.  
26.     public bool CastLine() {
27.         Physics.Linecast(StartTransform.position, EndTransform.position, out hit, LayerMask);
28.         ProcessCollision(hit.collider);
29.         return hit.collider != null ? true : false;
30.     }
31.  
32.     private void ProcessCollision(Collider current) {
33.         // No collision this frame.
34.         if (current == null) {
35.             // But there was an object hit last frame.
36.             if (previous != null) {
37.                 DoEvent(OnRayExit, previous);
38.             }
39.         }
40.  
41.         // The object is the same as last frame.
42.         else if (previous == current) {
43.             DoEvent(OnRayStay, current);
44.         }
45.  
46.         // The object is different than last frame.
47.         else if (previous != null) {
48.             DoEvent(OnRayExit, previous);
49.             DoEvent(OnRayEnter, current);
50.         }
51.  
52.         // There was no object hit last frame.
53.         else {
54.             DoEvent(OnRayEnter, current);
55.         }
56.  
57.         // Remember this object for comparing with next frame.
58.         previous = current;
59.     }
60.  
61.     private void DoEvent(Action<Collider> action, Collider collider) {
62.         if (action != null) {
63.             action(collider);
64.         }
65.     }
66.  
67.     public static int GetLayerMask(string layerName, int existingMask=0) {
68.         int layer = LayerMask.NameToLayer(layerName);
69.         return existingMask | (1 << layer);
70.     }
71.  
72. }
73.  

[Edit] Various bug fixes and typos.
The above code hasn't been tested (except the RayCaster class).
I just whipped it up for a quick example, but should work.