粒子系统沿路径点动态移动实现方法

using UnityEngine;  
using System.Collections;  
using System.Collections.Generic;  
public class TestParticleMovement : MonoBehaviour  
{  
    public List<Vector3> nodes;     
    public Vector3[] directions;  
    private ParticleSystem particles;  
    void Start ()  
    {  
        GetComponent<ParticleSystem>().startLifetime = nodes.Count;  
        if (nodes.Count == 0)  
            Debug.LogError("请添加至少1个node");  
        //自动生成方向  
        directions = new Vector3[nodes.Count];  
        for (int i = 0; i < nodes.Count; i++)  
            directions[i] = (nodes[i] - ((i - 1 >= 0) ? nodes[i - 1] : transform.position));  
    }  
    void Update ()  
    {  
        particles = GetComponent<ParticleSystem>();  
        ParticleSystem.Particle[] particleList = new ParticleSystem.Particle[particles.particleCount];  
        int partCount = particles.GetParticles(particleList);  
        for (int i = 0; i < partCount; i++)  
        {  
            // 计算粒子当前的生命  
            float timeALive = particleList[i].startLifetime - particleList[i].lifetime;  
            float dist = GetAddedMagnitude((int) timeALive);  
            int count = 0;  
            //判断位置信息