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 tʹ. 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.
Given the specified normalized time t, typically in the range [0,1], returns the “eased” time tʹ, 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:
const te = d3.easeCubic(t);
To apply custom elastic easing, create your easing function before the animation starts:
const ease = d3.easeElastic.period(0.4);
Then during the animation, apply the easing function:
const te = ease(t);
See also transition.ease.
Source · Linear easing; the identity function; linear(t) returns t.
const linear = d3.easePoly.exponent(1); const quad = d3.easePoly.exponent(2); const cubic = d3.easePoly.exponent(3);
Sinusoidal easing; returns sin(t).
Reverse sinusoidal easing; equivalent to 1 - easeSinIn(1 - t).
Exponential easing; raises 2 to the exponent 10 × (t - 1).
Reverse exponential easing; equivalent to 1 - easeExpIn(1 - t).
Reverse circular easing; equivalent to 1 - easeCircleIn(1 - t).
Reverse elastic easing; equivalent to 1 - elasticIn(1 - t).
Returns a new elastic easing with the specified amplitude a. The amplitude a must be greater than or equal to 1.
Returns a new elastic easing with the specified period p.
Reverse anticipatory easing; equivalent to 1 - easeBackIn(1 - t).
Returns a new back easing with the specified overshoot s.
Bounce easing, like a rubber ball.
Reverse bounce easing; equivalent to 1 - easeBounceIn(1 - t).