What is the basis for the Feng Shui compass to adjust the longitude and latitude by 3 degrees?

There are many special terms in the Feng Shui Compass. I have also thought about the issue of scheduling numbers. My personal understanding is that it is closely related to the three aspects of heaven, man and earth. For example, the derivation method of "Taiyi Divine Number" also uses The whole hexagram is moved by one house. It is the same reason. It is said that the Japanese view of looking at the underworld is slightly different from the traditional Chinese way of looking north to south. The above is just for your reference.