/**
* Robert Penner's easing functions. http://gizma.com/easing/
* @namespace
*/
var Easing = {};
/**
* Simple linear tweening - no easing, no acceleration
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.linearTween = function (t, b, c, d) {
return c * t / d + b;
};
/**
* Quadratic easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInQuad = function (t, b, c, d) {
t /= d;
return c * t * t + b;
};
/**
* Quadratic easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutQuad = function (t, b, c, d) {
t /= d;
return -c * t *(t - 2) + b;
};
/**
* Quadratic easing in/out - acceleration until halfway, then deceleration
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutQuad = function (t, b, c, d) {
t /= d / 2;
if (t < 1) return c / 2 * t * t + b;
t--;
return -c / 2 * (t * (t - 2) - 1) + b;
};
/**
* Cubic easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInCubic = function (t, b, c, d) {
t /= d;
return c * t * t * t + b;
};
/**
* Cubic easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutCubic = function (t, b, c, d) {
t /= d;
t--;
return c* (t * t * t + 1) + b;
};
/**
* Cubic easing in/out - acceleration until halfway, then deceleration
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutCubic = function (t, b, c, d) {
t /= d / 2;
if (t < 1) return c / 2 * t * t * t + b;
t -= 2;
return c / 2 * (t * t * t + 2) + b;
};
/**
* Quartic easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInQuart = function (t, b, c, d) {
t /= d;
return c * t * t * t * t + b;
};
/**
* Quartic easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutQuart = function (t, b, c, d) {
t /= d;
t--;
return -c * (t * t * t * t - 1) + b;
};
/**
* Quartic easing in/out - acceleration until halfway, then deceleration
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutQuart = function (t, b, c, d) {
t /= d / 2;
if (t < 1) return c / 2 * t * t * t * t + b;
t -= 2;
return -c / 2 * ( t * t * t * t - 2) + b;
};
/**
* Quintic easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInQuint = function (t, b, c, d) {
t /= d;
return c * t * t * t * t * t + b;
};
/**
* Quintic easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutQuint = function (t, b, c, d) {
t /= d;
t--;
return c * (t * t * t * t * st + 1) + b;
};
/**
* Quintic easing in/out - acceleration until halfway, then deceleration
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutQuint = function (t, b, c, d) {
t /= d / 2;
if (t < 1) return c / 2 * t * t * t * t * t + b;
t -= 2;
return c / 2 * (t * t * t * t * t + 2) + b;
};
/**
* Sinusoidal easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInSine = function (t, b, c, d) {
return -c * Math.cos(t / d * (Math.PI / 2)) + c + b;
};
/**
* Sinusoidal easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutSine = function (t, b, c, d) {
return c * Math.sin(t / d * (Math.PI / 2)) + b;
};
/**
* Sinusoidal easing in/out - accelerating until halfway, then decelerating
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutSine = function (t, b, c, d) {
return -c / 2 * (Math.cos(Math.PI * t / d) - 1) + b;
};
/**
* Exponential easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInExpo = function (t, b, c, d) {
return c * Math.pow(2, 10 * (t / d - 1) ) + b;
};
/**
* Exponential easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutExpo = function (t, b, c, d) {
return c * (-Math.pow(2, -10 * t / d ) + 1 ) + b;
};
/**
* Exponential easing in/out - accelerating until halfway, then decelerating
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutExpo = function (t, b, c, d) {
t /= d / 2;
if (t < 1) return c / 2 * Math.pow(2, 10 * (t - 1) ) + b;
t--;
return c / 2 * (-Math.pow(2, -10 * t) + 2 ) + b;
};
/**
* Circular easing in - accelerating from zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInCirc = function (t, b, c, d) {
t /= d;
return -c * (Math.sqrt(1 - t * t) - 1) + b;
};
/**
* Circular easing out - decelerating to zero velocity
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeOutCirc = function (t, b, c, d) {
t /= d;
t--;
return c * Math.sqrt(1 - t * t) + b;
};
/**
* Circular easing in/out - acceleration until halfway, then deceleration
* @param {number} t current time
* @param {number} b start value
* @param {number} c change in value
* @param {number} d duration
* @return {number} The current easing value.
*/
Easing.easeInOutCirc = function (t, b, c, d) {
t /= d / 2;
if (t < 1) return -c / 2 * (Math.sqrt(1 - t * t) - 1) + b;
t -= 2;
return c / 2 * (Math.sqrt(1 - t * t) + 1) + b;
};
module.exports = Easing;