set term gif animate ...if your local gd libray supports the creation of animated gifs. Unfortunately, the quality of created animation is not adequate, probably because of limitation on the max number of colors.
There is another way to create animated gif
or video, that is, gathering series of truecolor pictures (png,jpeg)
with some external tools like
as
Back to
Part(1),
Part(2),
Part(3),
Part_Lighting
convert -adjoin foo***.png foo.gif
[*** are decimal number of the pictures]
gif terminal with option "animate": original scrips
(japanese)
By gathering png pictures.
Using a modified surface curve function to realize the rope having a circular section.