d3-ease ​

Examples · Easing is a method of distorting time to control apparent motion in animation. It is most commonly used for slow-in, slow-out. By easing time, animated transitions are smoother and exhibit more plausible motion.

The easing types in this module implement the ease method which takes a normalized time t and returns the corresponding “eased” time . Both the normalized time and the eased time are typically in the range [0,1], where 0 represents the start of the animation and 1 represents the end; some easing types, such as easeElastic, may return eased times slightly outside this range. A good easing type should return 0 if t = 0 and 1 if t = 1.

These easing types are largely based on work by Robert Penner.

ease(t) ​

Given the specified normalized time t, typically in the range [0,1], returns the “eased” time , also typically in [0,1]. 0 represents the start of the animation and 1 represents the end. A good implementation returns 0 if t = 0 and 1 if t = 1. For example, to apply easeCubic easing:

js
``const te = d3.easeCubic(t);``

To apply custom elastic easing, create your easing function before the animation starts:

js
``const ease = d3.easeElastic.period(0.4);``

Then during the animation, apply the easing function:

js
``const te = ease(t);``

easeLinear ​

Source · Linear easing; the identity function; linear(t) returns t.

easePoly ​

Source · Alias for easePolyInOut.

easePolyIn ​

Polynomial easing; raises t to the specified exponent. If the exponent is not specified, it defaults to 3, equivalent to easeCubicIn.

easePolyOut ​

Reverse polynomial easing; equivalent to 1 - easePolyIn(1 - t). If the exponent is not specified, it defaults to 3, equivalent to easeCubicOut.

easePolyInOut ​

Symmetric polynomial easing; scales easePolyIn for t in 0–0.5 and easePolyOut for t in 0.5–1. If the exponent is not specified, it defaults to 3, equivalent to easeCubic.

easePoly.exponent(e) ​

Returns a new polynomial easing with the specified exponent e. For example, to create equivalents of easeLinear, easeQuad, and easeCubic:

js
``````const linear = d3.easePoly.exponent(1);
const cubic = d3.easePoly.exponent(3);``````

Reverse quadratic easing; equivalent to 1 - easeQuadIn(1 - t). Also equivalent to easePolyOut.exponent(2).

Symmetric quadratic easing; scales easeQuadIn for t in 0–0.5 and easeQuadOut for t in 0.5–1. Also equivalent to easePoly.exponent(2).

easeCubic ​

Source · Alias for easeCubicInOut.

easeCubicIn ​

Cubic easing; equivalent to easePolyIn.exponent(3).

easeCubicOut ​

Reverse cubic easing; equivalent to 1 - easeCubicIn(1 - t). Also equivalent to easePolyOut.exponent(3).

easeCubicInOut ​

Symmetric cubic easing; scales easeCubicIn for t in 0–0.5 and easeCubicOut for t in 0.5–1. Also equivalent to easePoly.exponent(3).

easeSin ​

Source · Alias for easeSinInOut.

easeSinIn ​

Sinusoidal easing; returns sin(t).

easeSinOut ​

Reverse sinusoidal easing; equivalent to 1 - easeSinIn(1 - t).

easeSinInOut ​

Symmetric sinusoidal easing; scales easeSinIn for t in 0–0.5 and easeSinOut for t in 0.5–1.

easeExp ​

Source · Alias for easeExpInOut.

easeExpIn ​

Exponential easing; raises 2 to the exponent 10 × (t - 1).

easeExpOut ​

Reverse exponential easing; equivalent to 1 - easeExpIn(1 - t).

easeExpInOut ​

Symmetric exponential easing; scales easeExpIn for t in 0–0.5 and easeExpOut for t in 0.5–1.

easeCircle ​

Source · Alias for easeCircleInOut.

Circular easing.

easeCircleOut ​

Reverse circular easing; equivalent to 1 - easeCircleIn(1 - t).

easeCircleInOut ​

Symmetric circular easing; scales easeCircleIn for t in 0–0.5 and easeCircleOut for t in 0.5–1.

easeElastic ​

Source · Alias for easeElasticOut.

easeElasticIn ​

Elastic easing, like a rubber band. The amplitude and period of the oscillation are configurable; if not specified, they default to 1 and 0.3, respectively.

easeElasticOut ​

Reverse elastic easing; equivalent to 1 - elasticIn(1 - t).

easeElasticInOut ​

Symmetric elastic easing; scales elasticIn for t in 0–0.5 and elasticOut for t in 0.5–1.

easeElastic.amplitude(a) ​

Returns a new elastic easing with the specified amplitude a. The amplitude a must be greater than or equal to 1.

easeElastic.period(p) ​

Returns a new elastic easing with the specified period p.

easeBack ​

Source · Alias for easeBackInOut.

easeBackIn ​

Anticipatory easing like a dancer bending her knees before jumping off the floor. The degree of overshoot is configurable; if not specified, it defaults to 1.70158.

easeBackOut ​

Reverse anticipatory easing; equivalent to 1 - easeBackIn(1 - t).

easeBackInOut ​

Symmetric anticipatory easing; scales easeBackIn for t in 0–0.5 and easeBackOut for t in 0.5–1.

easeBack.overshoot(s) ​

Returns a new back easing with the specified overshoot s.

easeBounce ​

Source · Alias for easeBounceOut.

easeBounceIn ​

Bounce easing, like a rubber ball.

easeBounceOut ​

Reverse bounce easing; equivalent to 1 - easeBounceIn(1 - t).

easeBounceInOut ​

Symmetric bounce easing; scales easeBounceIn for t in 0–0.5 and easeBounceOut for t in 0.5–1.

Resources
Observable