A cube that statiic stay on the map, and a cube following player .
And detection of a player is inside the static cube is also provided.
The subfunction detection version is also provided, so you can detecting is a player in a cube or not at any position.
The static cube is created by center and radius (in Cube: init).
The cube following you only need radius , because it always centering at player ( in Cube_Player: init).