void Awake()
{
traceMainCamera = this;
DontDestroyOnLoad(gameObject);
}
void OnEnable()
{
rt = Resources.Load <Texture>("Textures/lightMap");
//tm = GameObject.FindObjectOfType<TraceMainCamera>();
tm = Resources.Load <GameObject> ("levelPublic/lightMapCamera").GetComponent <TraceMainCamera> ();
}