Easing
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            Cmn
fun interface Easing
 
CubicBezierEasing | 
                
                   A cubic polynomial easing.  | 
              
PathEasing | 
                
                   An easing function for an arbitrary   | 
              
Easing is a way to adjust an animation’s fraction. Easing allows transitioning elements to speed up and slow down, rather than moving at a constant rate.
Fraction is a value between 0 and 1.0 indicating our current point in the animation where 0 represents the start and 1.0 represents the end.
An Easing must map fraction=0.0 to 0.0 and fraction=1.0 to 1.0.