public void move() {
		Vector3d velocity = new Vector3d(cameraXP - cameraXN, 0, cameraZP
				- cameraZN);
		velocity.normalize();
		if (Double.isNaN(velocity.x)) {
			velocity = new Vector3d();
		}
		position.add(velocity);
		if (position.x < -maxX) {
			position.x = -maxX;
		} else if (position.x > maxX) {
			position.x = maxX;
		}
		if (position.z < -maxZ) {
			position.z = -maxZ;
		} else if (position.z > maxZ) {
			position.z = maxZ;
		}
	}