- optical illusion (Day's)
The line segments are all the same length. They appear longer at the top and bottom of the sine wave.
To New
# set default screen, pen and turtle values
ResetAll SetScreenSize [400 400] HideTurtle
SetSC Black SetPC Green SetPS 1 PenUp
End
To Go
New
For [X 180 540 6] [
SetXY (:X - 360) (150* Sine :X) - 16
PenDown Forward 32 PenUp]
End