协程

using UnityEngine;
using System.Collections;

public class CoroutineTest : MonoBehaviour {

    private Vector3 v = new Vector3();
    private float speed = 0.0375f;

    // Use this for initialization
    void Start () {

        StartCoroutine(Routine());
    }

    void FixedUpdate() {
        transform.position += v;
    }
    
    IEnumerator Routine() {
        v.z = speed;
        v.x = 0;
        yield return new WaitForSeconds(3f);
        v.x = -speed;
        v.z = 0;
        yield return new WaitForSeconds(3f);
        v.z = -speed;
        v.x = 0;
        yield return new WaitForSeconds(3f);
        v.z = 0;
        v.x = speed;
        yield return new WaitForSeconds(3f);
        StartCoroutine(Routine());
    }

}