Animation formulas

• t - current time
• b - start time
• c - change in value
• d - duration

Simple linear tweening - no easing, no acceleration

Math.linearTween = function (t, b, c, d) {
return c*t/d + b;
};

Quadratic easing in - accelerating from zero velocity

Math.easeInQuad = function (t, b, c, d) {
t /= d;
return c*t*t + b;
};

Quadratic easing out - decelerating to zero velocity

Math.easeOutQuad = function (t, b, c, d) {
t /= d;
return -c * t*(t-2) + b;
};

Quadratic easing in/out - acceleration until halfway, then deceleration

Math.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

Math.easeInCubic = function (t, b, c, d) {
t /= d;
return c*t*t*t + b;
};

Cubic easing out - decelerating to zero velocity

Math.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

Math.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

Math.easeInQuart = function (t, b, c, d) {
t /= d;
return c*t*t*t*t + b;
};

Quartic easing out - decelerating to zero velocity

Math.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

Math.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

Math.easeInQuint = function (t, b, c, d) {
t /= d;
return c*t*t*t*t*t + b;
};

Quintic easing out - decelerating to zero velocity

Math.easeOutQuint = function (t, b, c, d) {
t /= d;
t--;
return c*(t*t*t*t*t + 1) + b;
};

Quintic easing in/out - acceleration until halfway, then deceleration

Math.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

Math.easeInSine = function (t, b, c, d) {
return -c * Math.cos(t/d * (Math.PI/2)) + c + b;
};

Sinusoidal easing out - decelerating to zero velocity

Math.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

Math.easeInOutSine = function (t, b, c, d) {
return -c/2 * (Math.cos(Math.PI*t/d) - 1) + b;
};

Exponential easing in - accelerating from zero velocity

Math.easeInExpo = function (t, b, c, d) {
return c * Math.pow( 2, 10 * (t/d - 1) ) + b;
};

Exponential easing out - decelerating to zero velocity

Math.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

Math.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

Math.easeInCirc = function (t, b, c, d) {
t /= d;
return -c * (Math.sqrt(1 - t*t) - 1) + b;
};

Circular easing out - decelerating to zero velocity

Math.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

Math.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;
}; 