Spring.

 Bahan baru buat ide jahil besok, :)

#code
from visual import *
from random import uniform,random
from visual.controls import *

display(center=(0,0,0),background=(1,1,1), autoscale=False, range=(3,5,3),        
        width=600, height=600,  forward=(-1.4,-1.3,-1)) #arah kamera

distant_light(direction=(1,1,1), color=color.red)
spring = helix(pos=(0,2,1), axis=(5,0,0), radius=0.5, color=color.red)

dl  = .1
l   = 1.
def proses():
    global l,dl
    spring.length = l
    if l>2:
        l   = 2
        dl  *= -1
    elif l<.5:
        l   = .5
        dl  *= -1
    l   += dl

while 1:
    rate (19)
    proses()
    
    
    
    

    

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