!! We make random symetries of the shape.

!let a_=!randint 0,1
!let b_=!randint 0,1
!let c_=!randint 0,1
!let C_=
!for i=1 to $nc
	!let x_=!item 2*$i-1 of $cc
	!let y_=!item 2*$i of $cc
	!if $a_=1
		!exchange x_ and y_
	!endif
	!if $b_=1
		!let x_=$[-$x_]
	!endif
	!if $c_=1
		!let y_=$[-$y_]
	!endif
	!let C_=!append item $x_,$y_ to $C_
!next i
!let cc=$C_

