游戏AI-A*寻路(1)

public class AstarAI : MonoBehaviour {
    //持有组件的引用
    private CharacterController cha;
    private Seeker seeker;
    //目标的Transform
    public Transform targetPosition;
    public Path path;

    public float speed = 100;
    private float nextWaypointDistance = 3;

    private int currentWaypoint = 0;
    public float turnSpeed = 5;

    // Use this for initialization
    void Start () {
        cha = GetComponent<CharacterController>();
        seeker = GetComponent<Seeker>();
        //seeker添加一个回调函数，在寻路完成后调用此函数
        seeker.pathCallback += OnPathComplete;
        seeker.StartPath(transform.position, targetPosition.position);
    }

    private void FixedUpdate()
    {
        if(path == null)
        {
            return;
        }
        //如果当前路点大于路径上点数总和，已经到达终点
        if (currentWaypoint >= path.vectorPath.Count)
        {
            Debug.Log("arrive");
            return;
        }
        //向着下一个路径点进行移动
        Vector3 dir = (path.vectorPath[currentWaypoint] - transform.position).normalized;
        dir *= speed * Time.fixedDeltaTime;
        cha.SimpleMove(dir);

        Quaternion targetRotation = Quaternion.LookRotation(dir);
        transform.rotation = Quaternion.Lerp
            (transform.rotation, targetRotation, Time.fixedDeltaTime * turnSpeed);

        if ((Vector3.Distance(path.vectorPath[currentWaypoint], transform.position))
            < nextWaypointDistance)
        {
            currentWaypoint++;
            return;
        }

    }

    public void OnPathComplete(Path p)
    {
        Debug.Log("Find the path" + p.error);
        if(! p.error)
        {
            path = p;
            currentWaypoint = 0;
        }
    }

    private void OnDisable()
    {
        seeker.pathCallback -= OnPathComplete;
    }