Getting a moving sprite to face the direction of movement

I have a simple sprite that follows several waypoints automatically, the problem is I cannot get the sprite to rotate towards the next waypoint. I've tried searching google and have tried all sorts of different ideas. Not one of them has worked.

Here is my waypoint movement code

Code (CSharp):

1.  
2. using UnityEngine;
3. using System.Collections;
4.  
5. public class MoveEnemy : MonoBehaviour
6. {
7.     public Transform[] waypoints;
8.     public float speed;
9.  
10.     int waypointIndex;
11.     int endPoint;
12.  
13.     Enemy1 enemy1;
14.    
15.     void Start ()
16.     {
17.         waypointIndex = 0;
18.         endPoint = waypoints.Length - 1;
19.         enemy1 = GetComponent<Enemy1>();
20.     }
21.  
22.     void Update ()
23.     {
24.         MoveToWaypoint();
25.     }
26.    
27.     void MoveToWaypoint()
28.     {
29.         Vector3 dir = waypoints[waypointIndex].position - this.transform.position;
30.         if(dir.magnitude > .05f)
31.         {
32.             this.transform.Translate( dir.normalized * speed * Time.deltaTime );
33.         }
34.         else
35.         {
36.             if(waypointIndex == endPoint)
37.                 enemy1.Die();
38.             else
39.                 waypointIndex++;
40.         }
41.     }
42. }
43.  

The sprite will start at the top of the screen and initially will move down before move back towards the top of the screen. Its initial facing is down.

The waypoints are located at:

1. 1,3,0
2. 2,0,0
3. 4,-2,0
4. 6,0,0
5. 4,3,0
6. 4,6,0

 

http://docs.unity3d.com/ScriptReference/Transform.LookAt.html

 

Something like this could do it.

Code (CSharp):

1. void MoveToWaypoint()
2.     {
3.         Vector3 dir = waypoints[waypointIndex].position - this.transform.position;
4.         if(dir.magnitude > .05f)
5.         {
6.             this.transform.Translate( dir.normalized * speed * Time.deltaTime );
7.             targetRot = Mathf.Atan2(dir.normalized.y, dir.normalized.x) * Mathf.Rad2Deg;
8.             transform.rotation = Quaternion.Euler(new Vector3(0, 0, targetRot));
9.         }
10.         else
11.         {
12.             if(waypointIndex == endPoint)
13.                 enemy1.Die();
14.             else
15.                 waypointIndex++;
16.         }
17.     }

 

@hawken Already tried LookAt and it didn't work. When I run the code, the sprite rotates on all 3 axis.

@LiberLogic969 This didn't work either, the sprite made an arc as it visited each waypoint.

I appreciate both of your suggestions.

 

That is strange. The rotation should just snap towards the next point immediately. Have you experimented with the different overloads of the Translate method?

Code (CSharp):

1. transform.Translate(dir.normalized * speed * Time.deltaTime, Space.World);
2.  
3. // OR
4.  
5. transform.Translate(dir.normalized * speed * Time.deltaTime, Space.Self);

You may also want to try simply adding your enemy sprite to a child of the main enemy GameObject and hold a reference to it in your script, then rotate its transform instead of the whole enemy GameObject, something like this :

Code (CSharp):

1.  
2.  
3. public Transform SpriteContainer;
4.  
5. void MoveToWaypoint()
6.         {
7.             Vector3 dir = waypoints[waypointIndex].position - this.transform.position;
8.             if(dir.magnitude > .05f)
9.             {
10.                 this.transform.Translate( dir.normalized * speed * Time.deltaTime );
11.  
12.                 targetRot = Mathf.Atan2(dir.normalized.y, dir.normalized.x) * Mathf.Rad2Deg;
13.                 SpriteContainer.rotation = Quaternion.Euler(new Vector3(0, 0, targetRot));
14.             }
15.             else
16.             {
17.                 if(waypointIndex == endPoint)
18.                     enemy1.Die();
19.                 else
20.                     waypointIndex++;
21.             }
22.         }
23.  

Sometimes this could solve issues like the one you are having, in my experience at least.

 

Code (CSharp):

1. transform.Translate(dir.normalized * speed * Time.deltaTime, Space.World);

This worked! Thank you so much!