How the rule works
The whole content of the cell turns by the same number of degrees from cell to cell, 90 or 180, clockwise or counterclockwise. The figure, the lines along the edge and the dot turn together, as if the paper itself were turned.
The difference from a figure merely rotating is that everything comes along. A task where the lines along the edge change place at the same time as the figure turns is almost always a rotation of the whole cell. Fix your eye on one corner and follow it.