判断物体是否在摄像机内

void Start(){
Rect screenRect  = new Rect(0, 0, Screen.width, Screen.Height);
}

void Update{
Vector3 screenPos = targetCamera.WorldToScreenPoint(objTrans.position);
if(!screenRect.Contains(screenPos)){
//do what you want
Debug.log("Obj has gone out of screen...");
}
}