[Carousel Wrap Use- Noob Question]

mm.. I understand the concept to go from y-0% to y-100%.but when the page loads the ticks are given a random offset from the top. each one of them has a different duration and then once they exit the view they start at the top without the offset.  I guess that is why they are the pros cause they good..  can't wrap my head around this one... how to reset animation once they leave viewport and continue...

[Carousel Wrap Use- Noob Question]

Saw this website http://www.invstr.com that uses Greensock. I was wondering how the background ticks(grey rectangles) were in a animated loop that when they past the viewport they automatically started at the top again... could that be achieved somehow with modifiers plugin like the carousel wrap example?

 

Thanks