固定路径寻路

转自：胡胜博客http://blog.youkuaiyun.com/husheng0/article/details/48233651
把路径封装成一个对象：

using UnityEngine;  
using System.Collections;  

public class Path: MonoBehaviour  
{  
    public bool isDebug = true;  
    public float Radius = 2.0f;  
    public Vector3[] pointA;        //导航点  

    public float Length  
    {  
        get  
        {  
            return pointA.Length; //返回数组长度  
        }  
    }  

    public Vector3 GetPoint(int index)  
    {  
        return pointA[index];      //返回导航数字  
    }  

    /// <summary>  
    /// Show Debug Grids and obstacles inside the editor  
    /// </summary>  
    void OnDrawGizmos()  
    {  
        if (!isDebug)  
            return;  

        for (int i = 0; i < pointA.Length; i++)  
        {  
            if (i + 1 < pointA.Length)  
            {  
                Debug.DrawLine(pointA[i], pointA[i + 1], Color.red);  
            }  
        }  
    }  
}

这个脚本让谁移动添就加到谁身上

using UnityEngine;  
using System.Collections;  

public class VehicleFollowing : MonoBehaviour   
{  
    public Path path;  
    public float speed = 20.0f;    //速度  
    public float mass = 5.0f;      //质量  
    public bool isLooping = true;  //是否循环运动  

    //Actual speed of the vehicle   
    private float curSpeed;  

    private int curPathIndex;    //开始时所在的导航点  
    private float pathLength;    //整个路径的长度  
    private Vector3 targetPoint; //下一个导航点  

    Vector3 velocity;  

    // Use this for initialization  
    void Start ()   
    {  
        pathLength = path.Length;  
        curPathIndex = 0;          

        //get the current velocity of the vehicle  
        velocity = transform.forward;  
    }  

    // Update is called once per frame  
    void Update ()   
    {  
        //Unify the speed  
        curSpeed = speed * Time.deltaTime;  

        targetPoint = path.GetPoint(curPathIndex);  

        //If reach the radius within the path then move to next point in the path  
        if(Vector3.Distance(transform.position, targetPoint) < path.Radius)  
        {  
            //Don't move the vehicle if path is finished   
            if (curPathIndex < pathLength - 1)  //判断是否到了终点  
                curPathIndex ++;  
            else if (isLooping)  
                curPathIndex = 0;  
            else  
                return;  
        }  

        //Move the vehicle until the end point is reached in the path  
        if (curPathIndex >= pathLength )  
            return;  

        //Calculate the next Velocity towards the path  
        if(curPathIndex >= pathLength - 1 && !isLooping)  
            velocity += Steer(targetPoint, true);   //Steer计算加速度  
        else  
            velocity += Steer(targetPoint);  

        transform.position += velocity; //Move the vehicle according to the velocity  
        transform.rotation = Quaternion.LookRotation(velocity); //Rotate the vehicle towards the desired Velocity  
    }  

    //Steering algorithm to steer the vector towards the target  
    public Vector3 Steer(Vector3 target, bool bFinalPoint = false)  
    {  
        //Calculate the directional vector from the current position towards the target point  
        Vector3 desiredVelocity = (target - transform.position);  
        float dist = desiredVelocity.magnitude;  

        //Normalise the desired Velocity  
        desiredVelocity.Normalize();  

        //Calculate the velocity according to the speed  
        if (bFinalPoint && dist < 10.0f)  
            desiredVelocity *= (curSpeed * (dist / 10.0f));  
        else   
            desiredVelocity *= curSpeed;  

        //Calculate the force Vector  
        Vector3 steeringForce = desiredVelocity - velocity;   
        Vector3 acceleration = steeringForce / mass;  

        return acceleration;  
    }  
}