AnimationControllerのアニメーションに割り込み

Warikomi.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Playables;
using UnityEngine.Animations;

public class Warikomi : MonoBehaviour {

	PlayableGraph graph;
	AnimatorControllerPlayable controllerPlayable;
	AnimationMixerPlayable mixer;

	[SerializeField] AnimationClip clip = null; // 特殊アニメーション
	[SerializeField] RuntimeAnimatorController controller = null;

	[SerializeField, Range(0, 1)] float speed = 1;

	void Awake()
	{
		graph = GetComponent<Animator> ().playableGraph;
	}

	IEnumerator Start () 
	{
		// AnimationControllerのPlayableを取得して、Mixerに登録
		controllerPlayable = AnimatorControllerPlayable.Create (graph, controller);
		mixer = AnimationMixerPlayable.Create (graph, 2, true);
		mixer.ConnectInput (0, controllerPlayable, 0);
		mixer.SetInputWeight (0, 1);
		GetComponent<Animator> ().playableGraph.GetOutput (0).SetSourcePlayable (mixer);

		// スペースキーが押されるまで待つ
		yield return new WaitUntil (() => Input.GetKeyDown (KeyCode.Space));

		// Playableを登録
		var playable = AnimationClipPlayable.Create (graph, clip);
		mixer.ConnectInput (1, playable, 0);

		// アニメーションを切替、終了まで待ち、AnimationControllerに戻す
		yield return Mix(0.3f, 0, 1);
		yield return new WaitForSeconds (clip.length - 0.3f);
		yield return Mix(0.3f, 1, 0);

		// 不要なPlayableを破棄
		graph.Disconnect (mixer, 1);
		playable.Destroy ();
	}

	IEnumerator Mix(float time, int fromInput, int toInput)
	{
		var waitTime = Time.timeSinceLevelLoad + time;
		yield return new WaitWhile (() => {
			var diff = waitTime - Time.timeSinceLevelLoad;
			if( diff <= 0){
				mixer.SetInputWeight(fromInput, 0);
				mixer.SetInputWeight(toInput, 1);
				return false; 
			}
			else{
				var rate = Mathf.Clamp01(diff / time);
				mixer.SetInputWeight(fromInput, rate);
				mixer.SetInputWeight(toInput, 1- rate);
				return true;
			}
		});
	}

	void Update()
	{
		controllerPlayable.SetFloat ("Speed", speed);
	}

	void OnDestroy()
	{
		graph.Destroy ();
	}
}