Basic AI Rotation

i am using the following code attached to a capsule to represent an enemy. the capsule has a child cylinder rotation = (90, 0, 0) and position = (0, 0, 1.75) to act as a pointer. when the capsule hits anything with a collider it will bounce.

the code works "almost" the way it should, but is off by a slight amount... anyone have any ideas to make this working properly?

demo project:
http://www.magestorm.com/temp/BasicAI.unitypackage

thanks in advance for any help with this!

Code (csharp):

1.  
2. using UnityEngine;
3.  
4. public class AIMovement : MonoBehaviour
5. {
6.     public float minSpeed = 3;
7.     public float maxSpeed = 7;
8.  
9.     private Vector3 velocity;
10.  
11.     ContactPoint hit;
12.  
13.     void Start()
14.     {
15.         float mySpeed1 = Random.Range(minSpeed, maxSpeed);
16.         float mySpeed2 = Random.Range(minSpeed, maxSpeed);
17.  
18.         velocity = new Vector3(mySpeed1, 0, mySpeed2);
19.     }
20.  
21.     void FixedUpdate()
22.     {
23.         // lock up/down movement
24.         velocity.y = 0;
25.  
26.         transform.Translate(velocity * Time.deltaTime, Space.World);
27.  
28.         //rotate so pointer is pointing at forward movement direction
29.         transform.rotation = Quaternion.LookRotation(hit.normal);
30.     }
31.  
32.     void OnCollisionEnter(Collision coll)
33.     {
34.         hit = coll.contacts[0];
35.  
36.         velocity = Vector3.Reflect(velocity, hit.normal); // reflect the velocity
37.     }
38.  
39. }
40.  

 

It is not a good idea to use a Physics based call back in a translation based system. You are attempting to use the physics system to give you a response, when you are not letting the physics system manage the movement.

In your case, I would simply let the physics do the work. give it a rigidbody, and just set it's velocity rather than translate the object. You will get much better results that way.

 

very helpful link:
http://answers.unity3d.com/questions/196896/help-with-bounce-agnle-and-velocity-change.html?sort=oldest

final code:

Code (csharp):

1.  
2. using UnityEngine;
3.  
4. public class AIMovement : MonoBehaviour
5. {
6.     public float startVel = 5;
7.     private Vector3 velocity;
8.  
9.     void Start()
10.     {
11.         velocity = new Vector3(0, 0, startVel);//move only in the forward direction
12.     }
13.  
14.     void FixedUpdate()
15.     {
16.         velocity.y = 0; // make sure velocity is strictly horizontal
17.         transform.Translate(velocity * Time.deltaTime, Space.World);
18.     }
19.  
20.     void OnCollisionEnter(Collision coll)
21.     {
22.         if (coll.collider.tag == "Wall" || coll.collider.tag == "Player")
23.         {
24.             ContactPoint hit = coll.contacts[0];
25.  
26.             Vector3 normal = hit.normal;
27.             normal.y = 0;
28.  
29.             Debug.DrawRay(hit.point, normal, Color.green, 0.3f); // draw green normal
30.             Debug.DrawRay(hit.point, -velocity, Color.red, 0.3f); // draw red "in" velocity
31.            
32.             velocity = Vector3.Reflect(velocity, normal); // reflect the velocity
33.  
34.             Ray ray = new Ray(hit.point, velocity);
35.             transform.LookAt(transform.position + ray.direction);
36.  
37.             Debug.DrawRay(hit.point, velocity, Color.blue, 0.3f); // draw blue "out" velocity
38.         }
39.     }
40.  
41. }
42.