using System.Collections.Generic;
using UnityEngine;

namespace Core.Utility
{
    /// <summary>
    /// 贝塞尔曲线
    /// </summary>
    public class BesselPath
    {
        public List<Vector3> PosList;

        public void SetPos(List<Vector3> PosList)
        {
            this.PosList = PosList;
        }

        public float GetPathCount(int count)
        {
            float step = 1f / count;
            Vector3 startPos = GetValue(0);
            float d = 0;
            for (int i = 1; i < count; i++)
            {
                Vector3 currPos = GetValue(step * i);
                d += Vector3.Distance(startPos, currPos);
            }

            return d;
        }

        public Vector3 GetValue(float t)
        {
            Vector3 a = PosList[0];
            for (int i = 1; i < PosList.Count; i++)
            {
                Vector3 b = PosList[i];
                Vector3 c = Vector3.Lerp(a, b, t);
                a = c;
            }

            return a;
        }
    }
}