README.md

Easing & Timing PHP Functions

composer require smnandre/easing-functions

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EasingFunctions is a PHP library that provides a collection of easing functions commonly used in animations, transitions, and smooth interpolations.

It includes standard easing equations: quadratic, cubic, quartic, quintic, sine, exponential, circular, elastic, and bounce functions.

Each of them is available in three variations:

• In: The motion starts slowly and accelerates.
• Out: The motion starts quickly and decelerates.
• InOut: A combination of both, accelerating at the start and decelerating at the end.

Easing Functions

x	In	InOut	Out
Cubic	easeInCubic	easeOutCubic	easeInOutCubic
Quart	easeInQuart	easeOutQuart	easeInOutQuart
Quad	easeInQuad	easeOutQuad	easeInOutQuad
Quint	easeInQuint	easeOutQuint	easeInOutQuint
Sine	easeInSine	easeOutSine	easeInOutSine
Expo	easeInExpo	easeOutExpo	easeInOutExpo
Circ	easeInCirc	easeOutCirc	easeInOutCirc
Back	easeInBack	easeOutBack	easeInOutBack
Bounce	easeInBounce	easeOutBounce	easeInOutBounce
Elastic	easeInElastic	easeOutElastic	easeInOutElastic

Installation

composer require smnandre/easing-functions

Usage

Easing\Functions::easeOutCubic(0);
// 0
Easing\Functions::easeOutCubic(0.5);
// 0.875

$values = array_map(Easing\Functions::easeOutCubic(...), range(0, 1, 0.1));
echo implode(" ", $values);
// 0 0.271 0.488 0.657 0.784 0.875 0.936 0.973 0.992 0.999 1

Functions

Easing Functions

Name	Formulae	Preview
easeOutCubic	$1 - pow(1 - x, 3)$
easeInOutCubic	$x < 0.5 ? 4 * pow(x, 3) : 1 - pow(-2 * x + 2, 3) / 2$
easeInQuart	$pow(x, 4)$
easeOutQuart	$1 - pow(1 - x, 4)$
easeInOutQuart	$x < 0.5 ? 8 * pow(x, 4) : 1 - pow(-2 * x + 2, 4) / 2$
easeInCubic	$pow(x, 3)$
easeInQuad	$x * x$
easeOutQuad	$1 - (1 - x) * (1 - x)$
easeInOutQuad	$x < 0.5 ? 2 * x * x : 1 - pow(-2 * x + 2, 2) / 2$
easeInQuint	$pow(x, 5)$
easeOutQuint	$1 - pow(1 - x, 5)$
easeInOutQuint	$x < 0.5 ? 16 * pow(x, 5) : 1 - pow(-2 * x + 2, 5) / 2$
easeInSine	$1 - cos((x * pi()) / 2)$
easeOutSine	$sin((x * pi()) / 2)$
easeInOutSine	$-(cos(pi() * x) - 1) / 2$
easeInExpo	$x == 0 ? 0 : pow(2, 10 * x - 10)$
easeOutExpo	$x == 1 ? 1 : 1 - pow(2, -10 * x)$
easeInOutExpo	$x == 0 ? 0 : x == 1 ? 1 : x < 0.5 ? pow(2, 20 * x - 10) / 2 : (2 - pow(2, -20 * x + 10)) / 2$
easeInCirc	$1 - sqrt(1 - pow(x, 2))$
easeOutCirc	$sqrt(1 - pow(x - 1, 2))$
easeInOutCirc	$x < 0.5 ? (1 - sqrt(1 - pow(2 * x, 2))) / 2 : (sqrt(1 - pow(-2 * x + 2, 2)) + 1) / 2$
easeInBack	$2.70158 * pow(x, 3) - 1.70158 * pow(x, 2)$
easeOutBack	$1 + 2.70158 * pow(x - 1, 3) + 1.70158 * pow(x - 1, 2)$
easeInOutBack	$x < 0.5 ? (pow(2 * x, 2) * ((3.59258 * 2 * x) - 2.59258)) / 2 : (pow(2 * x - 2, 2) * ((3.59258 * (x * 2 - 2)) + 2.59258) + 2) / 2$
easeInBounce	$1 - easeOutBounce(1 - x)$
easeOutBounce	See bounceOut function
easeInOutBounce	$x < 0.5 ? (1 - easeOutBounce(1 - 2 * x)) / 2 : (1 + easeOutBounce(2 * x - 1)) / 2$
easeInElastic	$x == 0 ? 0 : x == 1 ? 1 : -pow(2, 10 * x - 10) * sin((x * 10 - 10.75) * ((2 * pi()) / 3))$
easeOutElastic	$x == 0 ? 0 : x == 1 ? 1 : pow(2, -10 * x) * sin((x * 10 - 0.75) * ((2 * pi()) / 3)) + 1$
easeInOutElastic	$x == 0 ? 0 : x == 1 ? 1 : x < 0.5 ? -(pow(2, 20 * x - 10) * sin((20 * x - 11.125) * ((2 * pi()) / 4.5))) / 2 : (pow(2, -20 * x + 10) * sin((20 * x - 11.125) * ((2 * pi()) / 4.5))) / 2 + 1$

License

This project is licensed under the MIT License. See the LICENSE file for more information.