public void move(int xa, int ya) {
		if (xa != 0 && ya != 0) {
			move(xa, 0);
			move(0, ya);
			numSteps--;
			return;
		}
		numSteps++;
		if (!hasCollided(xa, ya)) {
			if (ya < 0)
				movingDir = 0;
			if (ya > 0)
				movingDir = 1;
			if (xa < 0)
				movingDir = 2;
			if (xa > 0)
				movingDir = 3;
			x += xa * speed;
			y += ya * speed;
		}
	}