在网上看到一个平滑算法,很好用,经过我测试 效率很高,Chaikin 函数调用2-3次会获得一个相对较好的曲线。算法链接
原理是不断的裁切三角形让其分裂成2个三角,2个三角变成4个,以此类推,最终会越来越平滑从而接近一个圆。

裁切范例

平滑算法如下:

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using UnityEngine;
using System.Collections;
[RequireComponent(typeof(LineRenderer))]
public class SmoothAlgorithm : MonoBehaviour
{
private float minRadius = 1.5f;
private float maxRadius = 3.5f;
private int num = 25;
private LineRenderer lr;
private Vector3[] points;
void Start()
{
lr = GetComponent<LineRenderer>();
GenerateRandomPath();
SetLR(points);
}
void GenerateRandomPath()
{
points = new Vector3[num];
float angle = 360.0f / num;
for (int i = 0; i < num; i++)
{
points[i] = Quaternion.AngleAxis((angle * i), Vector3.forward) * Vector3.up * Random.Range(minRadius, maxRadius);
}
}
void SetLR(Vector3[] pts)
{
lr.SetVertexCount(pts.Length);
for (int i = 0; i < pts.Length; i++)
{
lr.SetPosition(i, pts[i]);
}
}
void Update()
{
if (Input.GetKeyDown(KeyCode.Space))
{
points = Chaikin(points);
SetLR(points);
}
if (Input.GetKeyDown(KeyCode.G))
{
GenerateRandomPath();
SetLR(points);
}
}
Vector3[] Chaikin(Vector3[] pts)
{
Vector3[] newPts = new Vector3[(pts.Length - 2) * 2 + 2];
newPts[0] = pts[0];
newPts[newPts.Length - 1] = pts[pts.Length - 1];
int j = 1;
for (int i = 0; i < pts.Length - 2; i++)
{
newPts[j] = pts[i] + (pts[i + 1] - pts[i]) * 0.75f;
newPts[j + 1] = pts[i + 1] + (pts[i + 2] - pts[i + 1]) * 0.25f;
j += 2;
}
return newPts;
}
}