[Unity] X-Axis flip to SpriteShapeController spline

SpriteShapeFlip.cs

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.U2D;
#if UNITY_EDITOR
using UnityEditor;
#endif

public class SpriteShapeFlip {
    
#if UNITY_EDITOR
    [MenuItem("CONTEXT/SpriteShapeController/FlipX")]
    public static void FlipX(MenuCommand command) {
        var target = (SpriteShapeController) command.context;
        if (target == null)
            return;

        var lst = new List<Vector3>();
        var min = float.MaxValue;
        var max = float.MinValue;
        for (var i = 0; i < target.spline.GetPointCount(); i++) {
            var p = target.spline.GetPosition(i);
            lst.Add(p);
            
            min = Mathf.Min(min, p.x);
            max = Mathf.Max(max, p.x);
        }
        
        Undo.RecordObject(target, "SpriteShapeController FlipX");
        
        for (var i = 0; i < lst.Count; i++) {
            var p = lst[i];
            p.x = max - (p.x - min);
            target.spline.SetPosition(i, p);
            
            var lt = target.spline.GetLeftTangent(i);
            lt.x = -lt.x;
            target.spline.SetLeftTangent(i, lt);
            
            var rt = target.spline.GetRightTangent(i);
            rt.x = -rt.x;
            target.spline.SetRightTangent(i, rt);
        }

        target.RefreshSpriteShape();
    }
#endif
        
}