Shanghai police posts diagram to provide women guidance on how men's lurking eyes can lead to sexual harrassment.

If the diagram is confusing already with its multiple diagrams, consider the English translation of the explanation:

“If the eyes of the ‘observer’, i.e. the point E, is right on the extension of segment BC, then point B would fall into his eyesight. Then, let’s make another line of DE which goes through E and is perpendicular to the extension of AC, then the right triangle of DEC is similar to the right triangle of ABC. So clearly, the length of DC is the horizontal distance between the man’s eye and the lady’s skirt. Ladies, have you figured that out?”