private double launchAngle(double launchX, double launchY) {
		double goalX = (GOAL_X + 1) * 30;
		double goalY = (GOAL_Y + 1) * 30;

		double degreeWant = Math.atan(Math.abs(goalY - launchY)
				/ Math.abs(goalX - launchX))
				* 180 / Math.PI;
		if (goalX - launchX > 0 && goalY - launchY > 0) {// in the first
															// octet
			return degreeWant;

		} else if (goalX - launchX < 0 && goalY - launchY > 0) {// in
																// the
																// second
																// octet
			return 180 - degreeWant;
		} else if (goalX - launchX < 0 && goalY - launchY < 0) {
			return 180 + degreeWant;
		}

		else if (goalX - launchX > 0 && goalY - launchY < 0) {// in the
																// 4th
																// octet
			return -degreeWant;
		} else {
			return 0;
		}

	}