How does the software of Feng Shui Compass determine the latitude and longitude?

Steps to find the current position with a compass: ① Make the actual terrain consistent with the map direction. ② Find two visible targets on the map. ③ Turn the running line (or long side) of the compass to one of the targets ④ Find a circle to match the arrow and pointer (north). ⑤ Place the circle in the north of the map without changing its direction. The tip of the long side of the compass matches the target on the map. ⑦ When the arrow of the circle draws a straight line with the extension line of the magnetic north line. Follow the same method for another goal. The intersection of two lines is where we are now. Use the compass to find the forward direction ① Make the straight line connecting the current position and destination match the forward line (long side) of the compass. ② The arrow of the circle is parallel to the magnetic north line (the arrow is in the upper part of the map). ③ Take the compass away from the map and hold it in front of you. ④ Twist your body until the arrow and pointer overlap. ⑤ The direction of the overlapping line is equal to the target direction of the map. If you want to measure latitude and longitude with mechanical equipment, you need a sextant.