private TetrisPiece getRandomPiece()
	{
		TetrisPiece tp;
		Random r=new Random();
		int s=r.nextInt(7);
		
		switch (s)
		{
		case 0:
			tp=new IPiece();
			break;
		case 1:
			tp=new LeftLPiece();
			break;
		case 2:
			tp=new LeftZPiece();
			break;
		case 3:
			tp=new RightLPiece();
			break;
		case 4:
			tp=new RightZPiece();
			break;
		case 5:
			tp=new SqPiece();
			break;
		default:
			tp=new TPiece();
			break;
		}
		 int t=r.nextInt(4);
		 for (int i=0;i<t;i++)
		 {
			 tp.rotateForward();
		 }
		 return tp;
	}