第一人称<ray>

using UnityEngine;
using System.Collections;

public class ray : MonoBehaviour {

    private Camera _camera;
    public GUISkin MySkin;
    public GameObject paodan;
    // Use this for initialization
    void Start () {
        _camera = GetComponent<Camera>();
    }

    // Update is called once per frame
    void Update () {
        if(Input.GetMouseButtonDown(0)){
            Vector3 point = new Vector3(_camera.pixelWidth/2,_camera.pixelHeight/2,0);
            Ray ray = _camera.ScreenPointToRay(point);
            RaycastHit hit;
            if(Physics.Raycast(ray,out hit)){
                GameObject hitobject = hit.transform.gameObject;
                ReactiveTarget target = hitobject.GetComponent<ReactiveTarget>();
                if(target != null){
                    Debug.Log("Target hit!");
                    target.ReactiveToHit();
                    Fenshu fenshu=GetComponent<Fenshu>();
                    fenshu.setCount();
                }
                else{
                    Debug.Log("hit"+hit.point);
                    StartCoroutine(SphereIndicator(hit.point));
                }
            }
        }
    }
    private IEnumerator SphereIndicator(Vector3 pos){
        GameObject sphere = Instantiate(paodan) as GameObject;
        sphere.transform.position = pos;

        yield return new WaitForSeconds(2);
        Destroy(sphere);
    }
    void OnGUI(){
        GUI.skin = MySkin;
        float size = 30f;
        float posX = _camera.pixelWidth/2 - size/2;
        float posY = _camera.pixelHeight/2 - size/2;
        GUI.Label(new Rect(posX,posY,size,size),"*");
    }
}