Smooth open/close door script coroutine issue

Question

I've just watched this video and grabbed the script from it. Here's an enhanced C# version of it. It works fine.

However, I decided that I want to make a Coroutine to open/close the door:

 void Update()
 {
     if (Input.GetKeyDown(KeyCode.E) && inSight) {
         open = !open;
         StartCoroutine(DoorCoroutine(open));
     }
 }

 IEnumerator DoorCoroutine(bool open)
 {
     Vector3 target = open ? openRot : defaultRot;
     float t = 0;
     while (t < 1) {
         t += Time.deltaTime / duration;
         cachedTransform.eulerAngles = Vector3.Slerp(cachedTransform.eulerAngles,
                                                     target,
                                                     t);
         yield return null;
     }
     cachedTransform.eulerAngles = target;
 }

It's doing the job well if I wait for it to finish, but the problem is, if I try to close/open the door while it's opening/closing, it doesn't act right. I understand that the problem is related to the fact, that when I call the closing coroutine while the opening one hasn't finished yet, they will conflict with each other and give wrong results.

I tried to stop the coroutine before calling it, didn't work. I also tried making the 't' variable a member field, not local, so that if the door hasn't finished rotating yet, and I tried to open/close it, 't' would resume and continue from where it left of. But it didn't quite work...

So, how can I write that coroutine properly? such that, if I open/close the door while it's closing/opening, it would react properly.

Thanks for any help.

EDIT:

Here's a video showing the door opening with and without the coroutine.

Answer 1

Here's one way, stopping the Coroutine and restarting it:

 void Update()
 {
     if (Input.GetKeyDown(KeyCode.E) && inSight)
         ToggleDoor();
 }

 void ToggleDoor()
 {
     open = !open;
     StopCoroutine("DoorCoroutine");
     StartCoroutine("DoorCoroutine", open);
 }

Here is one without Coroutines, using Animation instead:

 void Update()
 {
     if (Input.GetKeyDown(KeyCode.E) && inSight) 
         ToggleDoor();
 }

 void ToggleDoor()
 {
     open = !open;

     if (open)
         animation.Play("Open");
     else
         animation.Play("Close");
 }

Here's the really long way of achieving the same thing without having to use strings. I haven't tested it, but the code is so small so I'll take my chances of public embarrasment if it turns out to have bugs. :) If anything is wrong, I would suspect you may have to change the Current value to return null when you try to access it if it has been aborted, but I doubt it.

 AbortableEnumerator doorCoroutine;

 void ToggleDoor()
 {
     open = !open;

     StopDoorCoroutine ();
     StartDoorCoroutine ();
 }

 void StopDoorCoroutine ()
 {
     if (doorCoroutine != null)
         doorCoroutine.Abort ();
 }

 void StartDoorCoroutine ()
 {
     doorCoroutine = new AbortableEnumerator (DoorCoroutine (open));
     StartCoroutine (doorCoroutine);
 }

And the code that enables this new behaviour:

 public class AbortableEnumerator : IEnumerator
 {
     IEnumerator enumerator;
     bool isAborted;

     public AbortableEnumerator(IEnumerator enumerator)
     {
         this.enumerator = enumerator;
     }

     public void Abort()
     {
         isAborted = true;
     }

     bool IEnumerator.MoveNext ()
     {
         if (isAborted)
             return false;
         else
             return enumerator.MoveNext ();
     }

     void IEnumerator.Reset ()
     {
         isAborted = false;
         enumerator.Reset ();
     }

     object IEnumerator.Current 
     {
         get { return enumerator.Current; }
     }
 }

What I really think your approach should have been if you were to do it purely with code, but this is my preference and not a rule. Take it for a spin. I believe it behaves pretty nicely, and you can adjust the rotational angles and how fast it should smooth/move. If your world expects that the original rotation should be taken into account, you'd have to fix that.

Create a blank GO, attach this script to it.
Add a cube child to it, offset: 0.5, 0.5, 0.0, rotation: 0, 0, 0, scale: 1, 2, 0.1.
Press "E"
Tweak values in inspector to your hearts content

And the code:

 using UnityEngine;
 using System.Collections;
 
 public class SmallDoorExample : MonoBehaviour {
 
     public float closedAngle = 0;
     public float openedAngle = 90;
     public float doorSwingSmoothingTime = 0.5f;
     public float doorSwingMaxSpeed = 90;
 
     private float targetAngle;
     private float currentAngle;
     private float currentAngularVelocity;
 
     void Update () 
     {
         if (DoorWasInteractedWith ())
             ToggleAngle ();
 
         UpdateAngle ();
         UpdateRotation ();
     }
 
     static bool DoorWasInteractedWith ()
     {
         return Input.GetKeyDown (KeyCode.E);
     }
 
     void ToggleAngle ()
     {
         if (targetAngle == openedAngle)
             targetAngle = closedAngle;
         else
             targetAngle = openedAngle;
     }
 
     void UpdateAngle ()
     {
         currentAngle = Mathf.SmoothDamp (currentAngle, 
                                          targetAngle, 
                                          ref currentAngularVelocity, 
                                          doorSwingSmoothingTime, 
                                          doorSwingMaxSpeed);
     }
 
     void UpdateRotation ()
     {
         transform.localRotation = Quaternion.AngleAxis (currentAngle, Vector3.up);
     }
 }

Smooth open/close door script coroutine issue

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