var Enemy_tank: GameObject; //定义坦克
var firepoint: Transform; //定义开火点
var bullet: Rigidbody; //定义子弹
var bullspeed: int=50; //定义子弹速度
var attackRange = 100.0; //定义距离
var target : Transform;//定义共计目标
//static var value : float ;
private var cun_time: int=0;
function Start () //初始化目标
...........