画像を裏返すようなアニメーション

FlipImage.cs

/*********************************
 * Flipしたときに画像差し替えたいな
 * with DOTween
*********************************/
using System;

using UnityEngine;
using UnityEngine.UI;

using DG.Tweening;

public class FlipImage : Image
{
    private Sprite sourceImage;
    private bool isFlipped = false;

    public bool IsFlipped {
        get { return this.isFlipped; }
    }
    
    /// <summary>
    /// 裏返し
    /// </summary>
    /// <param name="duration">アニメーション秒</param>
    /// <param name="flipImage">裏返した時にセットする画像</param>
    public void Flip(float duration, Sprite flipImage)
    {
        Flip(duration, flipImage, null);
    }
    /// <summary>
    /// 裏返し
    /// </summary>
    /// <param name="duration">アニメーション秒</param>
    /// <param name="flipImage">裏返した時にセットする画像</param>
    /// <param name="callback">裏返し完了時によぶコールバック</param>
    public void Flip(float duration, Sprite flipImage, Action callback)
    {
        if (this.isFlipped) {
            return;
        }
        this.isFlipped = true;

        this.sourceImage = this.sprite;
        var seq = DOTween.Sequence();
        var rotation = this.rectTransform.rotation;
        var halfDuration = duration / 2f;
        seq.Append(
            this.rectTransform
            .DORotate(new Vector3(rotation.x, 90, rotation.z), halfDuration, RotateMode.FastBeyond360)
                .OnComplete(() => {
                    if (flipImage != null) {
                        this.sprite = flipImage;
                    }
                })
        );
        seq.Append(
            this.rectTransform
                .DORotate(new Vector3(rotation.x, -90, rotation.z), halfDuration, RotateMode.FastBeyond360)
                .SetRelative(true)
        );
        seq.OnComplete(() => {
            if (callback != null) {
                callback();
            }
        });

    }

    /// <summary>
    /// 戻す
    /// </summary>
    /// <param name="duration">アニメーション秒</param>
    public void Reverse(float duration)
    {
        Reverse(duration, null);
    }
    /// <summary>
    /// 戻す
    /// </summary>
    /// <param name="duration">アニメーション秒</param>
    /// <param name="callback">戻し完了時によぶコールバック</param>
    public void Reverse(float duration, Action callback)
    {
        if (!this.isFlipped) {
            return;
        }
        this.isFlipped = false;

        var seq = DOTween.Sequence();
        var rotation = this.rectTransform.rotation;
        var halfDuration = duration / 2f;
        seq.Append(
            this.rectTransform
                .DORotate(new Vector3(rotation.x, 90, rotation.z), halfDuration, RotateMode.FastBeyond360)
                .OnComplete(() => {
                    if (this.sourceImage != null) {
                        this.sprite = this.sourceImage;
                    }
                })
        );
        seq.Append(
            this.rectTransform
                .DORotate(new Vector3(rotation.x, -90, rotation.z), halfDuration, RotateMode.FastBeyond360)
                .SetRelative(true)
                .OnComplete(() => {
                    rotation.y = 0;
                    this.rectTransform.rotation = rotation;
                })
        );
        seq.OnComplete(() => {
            this.sourceImage = null;
            if (callback != null) {
                callback();
            }
        });
    }
    
}