'8-way flow model' is used for defining the flow direction in computer environment.
To show the current direction, there are numerical values which are shown in gray, defining the direction of the flow. For example, the value 1 is used to indicate the direction of flow, the value 32 is used to indicate the northwest direction and the value 2 is used to indicate the southeast direction.
a: Altitude information of cells,
b: Flow directios,
c: In this aspect, data tables which will be used in the software are displayed.