Question ping pong lerp help

i am trying to ping pong a lerp so it moves an object smooth so when hold mouse key it starts to travel to its end point but if release mouse key at any point it smooth travels back to its starting point using the same time duration it used before releasing the mouse button, i am in a bit of a pickle, can anyone help get this to work

Code (CSharp):

1. using UnityEngine;
2. public class LerpUpdate3 : MonoBehaviour
3. {
4.     Vector3 start_pos;
5.     Vector3 end_pos;
6.     Vector3 ofset= new Vector3(5,0,0);
7.     Vector3 current_pos;
8.  
9.     public float timer;
10.  
11.     public float duration;
12.  
13.  
14.  
15.  
16.     // Start is called before the first frame update
17.     void Start()
18.     {
19.         start_pos=transform.position;
20.         current_pos= transform.position;
21.         end_pos=transform.position+ofset;
22.        
23.     }
24.  
25.     // Update is called once per frame
26.     void Update()
27.     {
28.         if (Input.GetKey(KeyCode.Mouse0) && current_pos.x<end_pos.x)
29.         {
30.             current_pos.x=Mathf.SmoothStep(start_pos.x,end_pos.x,timer/duration);
31.             transform.position=current_pos;
32.             timer+=Time.deltaTime;
33.  
34.         }else{
35.  
36.             if (Input.GetKeyUp(KeyCode.Mouse0)){
37.  
38.                             current_pos.x=Mathf.SmoothStep(current_pos.x,start_pos.x,timer/duration);
39.             transform.position=current_pos;
40.             timer+=Time.deltaTime;
41.  
42.  
43.             }
44.        
45.        
46.        
47.     }
48. }
49. }

 

Smoothing movement between any two particular values:

https://forum.unity.com/threads/beginner-need-help-with-smoothdamp.988959/#post-6430100

You have currentQuantity and desiredQuantity.
- only set desiredQuantity
- the code always moves currentQuantity towards desiredQuantity
- read currentQuantity for the smoothed value

Works for floats, Vectors, Colors, Quaternions, anything continuous or lerp-able.

The code: https://gist.github.com/kurtdekker/fb3c33ec6911a1d9bfcb23e9f62adac4

Another approach would be to use a tweening package line LeanTween, DOTween or iTween.

 

It looks like you are expecting Input.GetKeyUp to return true any time the player is not pressing the mouse button. That's not how it works, though. Input.GetKeyUp is only true on the one frame where a key transitions from being pressed to not being pressed.

 

If I got the idea right, you can try this.

Code (CSharp):

1. using UnityEngine;
2. public class LerpUpdate3 : MonoBehaviour
3. {
4.     Vector3 start_pos;
5.     Vector3 end_pos;
6.     Vector3 ofset = new Vector3(5, 0, 0);
7.     Vector3 current_pos;
8.  
9.     float progress = 0;
10.  
11.  
12.     public float duration;
13.  
14.     void Start()
15.     {
16.         start_pos = transform.position;
17.         current_pos = transform.position;
18.         end_pos = transform.position + ofset;
19.  
20.     }
21.  
22.     void Update()
23.     {
24.         float step = (1f / duration) * Time.deltaTime;
25.  
26.         if (Input.GetKey(KeyCode.Mouse0))
27.         {
28.             progress += step;
29.         }
30.         else
31.         {
32.             progress -= step;
33.         }
34.  
35.         progress = Mathf.Clamp01(progress);
36.  
37.         current_pos.x = Mathf.SmoothStep(start_pos.x, end_pos.x, progress);
38.         transform.position = current_pos;
39.     }
40. }
41.  

 

thank so much, was getting in a muddle trying to feed the current position back in as the start position, just recovering from covid, think it has fried my grey matter

much appreciated all for help given

 

think i now have it working as i need thank you