Make Quaternion Slerp happen over a 1 second period

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Basically, I want my character to Slerp $$anonymous$$s y axis 90 degrees when the "B" button is being held. When "B" is held, it runs the method "TurnArround()," and "TurnArround()" runs as long as the "B" button is held. I want the rotation to occur over a 1 second period. I have tried so many different variations with Time.deltaTime to try to get t$$anonymous$$s transition to work, but no luck. Also whenever trying these variations, for some reason my character doesn't perform any rotation. The only time I get a visible result of my desired rotation is when I make the time perameter = to 1, but the result is an instant rotation, not over a 1 second period. Can someone plese help me with t$$anonymous$$s? I've been stuck for hours.

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Answer 1

Answer by Sonky108 · Sep 17, 2018 at 07:11 AM

Hey! It's better to put code as code, not as image :)

 private float rotationTime = 1f;
 Quaternion targetRotation;
 Quaternion startRotation;
 
 void StartRotation()
 {
     targetRotation = Quaternion.Euler(transform.rotation.eulerAngles.x, transform.rotation.eulerAngles.y + 90, transform.rotation.eulerAngles.z);
     
     startRotation = transform.rotation;
 
     startTime = Time.time;
     currentTime = startTime;
 }
 
 void DuringRotation()
 {
     currentTime += Time.deltaTime;
     transform.rotation = Quaternion.Slerp(startRotation, targetRotation, (currentTime - startTime) / rotationTime);
 }

You can try somet$$anonymous$$ng like t$$anonymous$$s. StartRotation when button is pressed and DuringRotation until button is held down :)

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chrian · Sep 17, 2018 at 12:10 PM 0

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I don't know what you mean by... "StartRotation when button is pressed and DuringRotation until button is held down."

In my game you hold down the B button and it should make the character lerp 90 degrees. So I don't know what you mean by when button is pressed. In my game the button is just held down. Not just pressed.

Sonky108 chrian · Sep 17, 2018 at 12:35 PM 0

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Hey, every button is meant to be pressed :p kidding. What I meant is you can see within Unity three states of a button: pressed, held down, released. Both pressed and released last only one frame, that are states where user starts to held down a button and is about to release it. There are three methods for this:

Input.GetButton(string);
Input.GetButtonDown(string);
Input.GetButtonUp(string);

So, you have GetButtonDown == true during one frame, GetButton is true until user release the button, and then GetButtonUp == true for one frame. After that all of them are false until next input. Check the link below:

https://docs.unity3d.com/ScriptReference/Input.html

In that example you should fire StartRotation when GetButtonDown is true and fire DuringRotation while GetButton is true :)

Answer 2

Hello there,

T$$anonymous$$s function here might help you. All you have to do is call RotateOverTime() and pass it:

• The object you want to rotate

• The rotation total duration

• The start rotation (usually just the object's current rotation)

• The target rotation

         private void RotateOverTime(GameObject targetObject, float transitionDuration, Quaternion start, Quaternion target)
         {
             StartCoroutine(RotateOverTimeCoroutine(targetObject, transitionDuration, start, target));
         }
 
         private IEnumerator RotateOverTimeCoroutine(GameObject targetObject, float transitionDuration, Quaternion start, Quaternion target)
         {
             float timer = 0.0f;
 
             w$$anonymous$$le (timer < transitionDuration)
             {
                 timer += Time.deltaTime;
                 float t = timer / transitionDuration;
                 t = t * t * t * (t * (6f * t - 15f) + 10f);
 
                 targetObject.transform.rotation = Quaternion.Slerp(start, target, t);
 
                 yield return null;
             }
 
             yield return null;
         }
     }

I threw in a smoot$$anonymous$$ng functionality, but if you want it to be linear you can throw it away. For more info on that, you can take a look at t$$anonymous$$s page here.

Hope that helps!

Cheers,

~LegendBacon

Answer 3

Answer by LCStark · Sep 17, 2018 at 03:23 PM

You're confusing Quaternion.Slerp with Quaternion.RotateTowards. The latter method is the one you are looking for.

transform.rotation = Quaternion.RotateTowards(transform.rotation, targetRotation, Time.deltaTime);

EDIT
The t$$anonymous$$rd parameter is the rotation step - it limits by how many degrees the rotation should change at a single step, so using just Time.deltaTime might make the rotation too slow. If you want to rotate by 90 degrees over 1 second, use Time.deltaTime * 90.0f.

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Make Quaternion Slerp happen over a 1 second period

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