Randomized Attack Animation RPG - unity3d

Question

First of all, I'm quite noob with animator and animation systems in unity.
What I'm trying to achieve (and I was trying with Animator component) is a randomized attack only while I keep my mouse button pressed on the enemy and which completes the execution of the attack clip that is playing even if i release the button meanwhile.
I tried adding my 2 attack animations to a list and play it, with something like
anim.Play(Random.Range(0, list.Count))
...but I don'tknow if the problem is that while I keep pressed one animation cancels the other or what.
Therefore I prefer to ask, because I'm probably doing things in the wrong way.
Thank you.

Answer 1

Yes the issue is probably what you said: You have to wait until one Animation finished before starting a new one otherwise you would start a new animation every frame.
You could use a Coroutine (also check the API) to do that.
Ofcourse the same thing could be implemented also only in Update without using a Coroutine but most of the times that becomes really cluttered and sometimes even more complicated to handle. And there is not really any loss or gain (regarding performance) in simply "exporting" it to a Coroutine.
// Reference those in the Inspector or get them elsewhere
public List<AnimationClip> Clips;
public AnimationClip Idle;
private Animator _anim;
// A flag to make sure you can never start the Coroutine multiple times
private bool _isAnimating;
private void Awake()
{
_anim = GetComponent<Animator>();
}
private void Update()
{
if(Input.GetMouseButtonDown(0)
{
// To make sure there is only one routine running
if(!_isAnimating)
{
StartCoroutine(RandomAnimations());
}
}
// This would immediately interrupt the animations when mouse is not pressed anymore
// uncomment if you prefer this otherwise the Coroutine waits for the last animation to finish
// and returns to Idle state afterwards
//else if(Input.GetMouseButtonUp(0))
//{
// // Interrupts the coroutine
// StopCoroutine (RandomAnimations());
//
// // and returns to Idle state
// _anim.Play(Idle.name);
//
// // Reset flag
// _isAnimating = false;
//}
}
private IEnumerator RandomAnimations()
{
// Set flag to prevent another start of this routine
_isAnimating = true;
// Go on picking clips while mouse stays pressed
while(Input.GetMouseButton(0))
{
// Pick random clip from list
var randClip = Clips[Random.Range(0, Clips.Count)];
// Switch to the random clip
_anim.Play(randClip.name);
// Wait until clip finished before picking next one
yield return new WaitForSeconds(randClip.length);
}
// Even if MouseButton not pressed anymore waits until the last animation finished
// then returns to the Idle state
// If you rather want to interrupt immediately if the button is released
// skip this and uncomment the else part in Update
_anim.Play(Idle.name);
// Reset flag
_isAnimating = false;
}
Note that this way of randomizing does not provide things like "Don't play the same animation twice in a row" or "Play all animations before repeating one".
If you want this checkout this answer to a very similar question. There I used a randomized list to run through so there are no doubles