Unity中穿过已经点生成平滑曲线

BezierCurve

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class BezierCurve {
    private static float scale = 0f;

    /// <summary>
    /// 缩放系数[0,1],0代表曲线,1代表原始线条
    /// </summary>
    public static float Scale
    {
        get
        {
            return scale;
        }

        set
        {
            scale = value;
        }
    }

    public static List<Vector3> CreateCurve(List<Vector3> originPoint)
    {
        int originCount = originPoint.Count;
        List<Vector3> midpoints = new List<Vector3>();
        //生成中点
        for (int i = 0; i < originCount; i++)
        {
            int nextI = (i + 1) % originCount;
            float midpointsX = (originPoint[i].x + originPoint[nextI].x) / 2.0f;
            float midpointsY = (originPoint[i].y + originPoint[nextI].y) / 2.0f;
            midpoints.Add(new Vector3(midpointsX, midpointsY));
        }

        //平移中点,index与originCount一一对应
        List<Vector3[]> extrapoints = new List<Vector3[]>();
        for (int i = 0; i < midpoints.Count; i++)
        {
            int firstIndex = (midpoints.Count - 1 + i) % midpoints.Count;
            int nextIndex = (midpoints.Count + i) % midpoints.Count;
            Vector3 midPoint = new Vector3();
            midPoint.x = (midpoints[firstIndex].x + midpoints[nextIndex].x) / 2.0f;
            midPoint.y = (midpoints[firstIndex].y + midpoints[nextIndex].y) / 2.0f;
            Vector3 destPoint = originPoint[i];
            float offsetX = destPoint.x - midPoint.x;
            float offsetY = destPoint.y - midPoint.y;
            Vector3 point1 = new Vector3(midpoints[firstIndex].x + offsetX, midpoints[firstIndex].y + offsetY);
            Vector3 point2 = new Vector3(midpoints[nextIndex].x + offsetX, midpoints[nextIndex].y + offsetY);
            point1 -= (point1 - destPoint) * Scale;
            point2 -= (point2 - destPoint) * Scale;
            extrapoints.Add(new Vector3[]{point1,point2});
        }

        //生成曲线
        List<Vector3> curvePoint = new List<Vector3>();
        {
            Vector3 p0 = originPoint[0];
            Vector3 p1 = extrapoints[1][0];
            Vector3 p2 = originPoint[1];
            List<Vector3> temp = GetBezier(p0, p1, p2);
            temp.RemoveAt(temp.Count - 1);
            curvePoint.AddRange(temp);
        }
        for (int i = 1; i < originPoint.Count - 2; i++)
        {
            Vector3 p0 = originPoint[i];
            Vector3 p1 = extrapoints[i][1];
            Vector3 p2 = extrapoints[i + 1][0];
            Vector3 p3 = originPoint[i + 1];
            List<Vector3> temp = GetBezier(p0, p1, p2, p3);
            temp.RemoveAt(temp.Count - 1);
            curvePoint.AddRange(temp);
        }
        {
            Vector3 p0 = originPoint[originPoint.Count - 2];
            Vector3 p1 = extrapoints[originPoint.Count - 2][1];
            Vector3 p2 = originPoint[originPoint.Count - 1];
            List<Vector3> temp = GetBezier(p0, p1, p2);
            temp.RemoveAt(temp.Count - 1);
            curvePoint.AddRange(temp);
        }
        curvePoint.Add(
            originPoint[originPoint.Count - 1]
            );

        return curvePoint;
    }

    //贝塞尔曲线 
    public static List<Vector3> GetBezier(Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, int pointCount = 10)
    {
        List<Vector3> ret = new List<Vector3>();
        float delta = 1.0f / (pointCount - 1.0f);
        for (int i = 0; i < pointCount; i++)
        {
            ret.Add(Bezier(p0, p1, p2, p3, i * delta));
        }
        return ret;
    }

    //贝塞尔曲线 
    public static List<Vector3> GetBezier(Vector3 p0, Vector3 p1, Vector3 p2, int pointCount = 10)
    {
        List<Vector3> ret = new List<Vector3>();
        float delta = 1.0f / (pointCount - 1.0f);
        for (int i = 0; i < pointCount; i++)
        {
            ret.Add(Bezier(p0, p1, p2, i * delta));
        }
        return ret;
    }

    //三阶贝塞尔曲线
    private static Vector3 Bezier(Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, float t)
    {
        return p0 * Mathf.Pow(1 - t, 3) + 3 * p1 * t * Mathf.Pow(1 - t, 2) + 3 * p2 * t * t * (1 - t) + p3 * t * t * t;
    }

    private static Vector3 Bezier(Vector3 p0, Vector3 p1, Vector3 p2, float t)
    {
        return p0 * Mathf.Pow(1 - t, 2) + 2 * t * (1 - t) * p1 + t * t * p2;
    }
}