Make collider work only if player faced in certain direction.

Just trying to make a collider work only if player is faced in a certain direction. Not sure where I'm going wrong. Any advice would be great. Hopefully you can see what I mean from the code.

Code (CSharp):

1.  
2. public class ScientistVanish : MonoBehaviour {
3.  
4.     public GameObject Scientist;
5.     public GameObject Pplayer;
6.     public float yRotation = -3;
7.  
8.  
9.  
10.     // Use this for initialization
11.     void Start () {
12.        
13.     }
14.    
15.     void OnTriggerEnter (Collider Pplayer) {
16.         if (Pplayer.gameObject.tag == "Player" && Pplayer.transform.rotation.y < yRotation)
17.         {
18.             Scientist.SetActive(false);
19.         }
20.        
21.     }
22. }
23.  

 

1) use CompareTag, not tag ==... nothing to do with your problem, it's just far more performant

2) Why is there a field named 'Pplayer' and you also have a parameter called 'Pplayer'? This makes for confusing naming conventions.

3) transform.rotation returns a Quaternion, the y component is going to be a value from -1 to 1. You may want 'eulerAngles' instead... but even then, there's no guarantee that the value will come out in the range you want since 270 and -90 are the same thing.

 

Cheers thanks for your insight.

 

I would use a Dot product.

Dot(currentForward,targetForward) basically means it performs a dot product comparison on how similar the currentforward is with the targetForward (in this example I'll use east). Dot will return a value from 1 to -1, where 1 is if the player is looking in the exact same direction (looking east), -1 means the player is looking in the exact opposite direction (looking west), and where 0 means they are looking exactly perpendicular (ie. north or south).

I prefer to use angle limits as they are more intuitive in the inspector (when you're looking for that specific angle), but in code I'll convert that value to a Dot Threshold and compare against that.

Code (CSharp):

1.  
2.     [Range(0,180)] public float angle = 90;
3.     public Gameobject Scientist;
4.  
5.    
6.     void OnTriggerEnter (Collider player)
7.     {
8.         if (!player.CompareTag("Player")) return;
9.  
10.         if(!LookingAt(player.transform, Scientist.transform, angle))
11.         {
12.             Scientist.SetActive(false);
13.         }
14.     }
15.  
16.     private bool LookingAt(Transform looker, Transform target, float angleLimit)
17.     {
18.         //find rotation that looks directly at target
19.         var targetLook = Quaternion.LookRotation(target.position - looker.position, looker.up);
20.  
21.         // even if clamped in the inspector, this ensures no shenanigans if the value was changed by code
22.         angleLimit = Mathf.PingPong(angleLimit,180);  
23.  
24.         // calc target Dot product threshold from provided angle
25.         var dot          = Mathf.Acos(angleLimit * Mathf.Deg2Rad);
26.  
27.         return Quaternion.Dot(looker.rotation,targetLook)>=dot;
28.     }
29.  

 

Thanks for taking the time to give me some help and more education.