Symmetric polynomial easing/easing factory; scales polyIn for t in [0, 0.5] and polyOut for t in [0.5, 1]. If the exponent is not specified, it defaults to 3, equivalent to cubic.
Symmetric polynomial easing/easing factory; scales polyIn for t in [0, 0.5] and polyOut for t in [0.5, 1]. If the exponent is not specified, it defaults to 3, equivalent to cubic.