Eases with an abrupt change in velocity either at the beginning (easeIn), the end (easeOut), or both (easeInOut). Circ is a convenience class that congregates the 3 types of Circ eases (CircIn, CircOut, and CircInOut) as static properties so that they can be referenced using the standard synatax, like Circ.easeIn, Circ.easeOut, and Circ.easeInOut.
GreenSock Docs (HTML5/JS)
Circ
