The other day at work I was trying to animate some tentacles moving around and overlapping. As I was struggling away my friend and colleague sat next to me (Kayn) saw what I was doing and decided to give me an old school Disney lesson in overlap. Which went as follows:
He handed me a sketch which looked like this one below:
He then asked me what would happen to the string if the top were to start moving to the right, as if someone pulled it. I drew this...
WRONG!!!
Though this felt like the only solution it was in fact incorrect. In my mind I thought "well the end of the string will want to stay at rest but I suppose it will have to move a bit". Well yes that is true but it won't look like the above. It will in fact look like the diagram below:
The end of the string moves to the left!! My mind blew up a little bit at this point. As the string is pulled it's height shortens causing the end to move up and left. Try this at home now by holding a pencil at one end and moving it right rapidly. The end will drag left first.
It also gives us this really wonderful S curve and curve reversal in the end of the string. This S curve appears again if the string were to stop moving too.
As Kayn corrected my drawing like the one above I could finally understand why my overlapping tentacles weren't looking too hot. Even though i felt like I grasped the concept of overlap, I didn't really understand it. And that's where the difference is. So, time to revisit all the principles and really understand the secret mechanics of them all.
