[] , [] , [^] , []Alternative of real thing / Swing(GC World : Sample ,Typical examples of GC)
This is a swing.
Let's move points.
What movement do you find?
Why does such movement occur?

GC/Win



Actual photograph
State of rest

State of pushing swing to the left

(Photographer:Yusaku Kanaya)

Forum of Geometric Constructor by Y.Iijima