Sean Yen

• Translated from the JavaScript in Sean Yen’s Easing equations
• Illustrations adapted from Andrey Sitnik and Ivan Solovev’s Easings.net

Example usage:

duration = 30
for frame in range(duration):
    return easeInOutQuad(frame/duration)

linear

def linear(t):
    return t

easeInSine

def easeInSine(t):
    import math
    return -math.cos(t * math.pi / 2) + 1

easeOutSine

def easeOutSine(t):
    import math
    return math.sin(t * math.pi / 2)

easeInOutSine

def easeInOutSine(t):
    import math
    return -(math.cos(math.pi * t) - 1) / 2

easeInQuad

def easeInQuad(t):
    return t * t

easeOutQuad

def easeOutQuad(t):
    return -t * (t - 2)

easeInOutQuad

def easeInOutQuad(t):
    t *= 2
    if t < 1:
        return t * t / 2
    else:
        t … See more →