Easing functions

See https://easings.net/. Interpolation range is [0-FRACUNIT].

Type	Function	Call arguments
Linear	ease.linear	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InSine	ease.insine	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
OutSine	ease.outsine	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InOutSine	ease.inoutsine	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InQuad	ease.inquad	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
OutQuad	ease.outquad	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InOutQuad	ease.inoutquad	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InCubic	ease.incubic	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
OutCubic	ease.outcubic	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InOutCubic	ease.inoutcubic	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InQuart	ease.inquart	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
OutQuart	ease.outquart	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InOutQuart	ease.inoutquart	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InQuint	ease.inquint	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
OutQuint	ease.outquint	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InOutQuint	ease.inoutquint	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InExpo	ease.inexpo	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
OutExpo	ease.outexpo	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InOutExpo	ease.inoutexpo	(fixed x, [fixed start, fixed end]), (fixed x, fixed end)
InBack	ease.inback	(fixed x, [fixed start/nil, fixed end/nil, [fixed param]]), (fixed x, fixed end)
OutBack	ease.outback	(fixed x, [fixed start/nil, fixed end/nil, [fixed param]]), (fixed x, fixed end)
InOutBack	ease.inoutback	(fixed x, [fixed start/nil, fixed end/nil, [fixed param]]), (fixed x, fixed end)