anymation

anymation

Simple stand-alone animation / tweening library. Currently works in node or in browsers w/ browserify.

Basic use

var Animation = require("anymation");

var objectToAnimate = {
   x: 40
};

var animation = new Animation({
   object: objectToAnimate,
   duration: 3000 // 3 seconds
}.tween("x", 40, 500); // Smoothly interpolate objectToAnimate.x between 40 and 500 over the course of the animation

// Your render loop is up to you

function render() {
   animation.update();
   // Draw / update what you need to based on objectToAnimate's properties
   // ...
   
   requestAnimationFrame(render);
}

render();

Easing functions

Anymation doesn't provide any built-in easing functions except for the trivial linear default. Specifying an easing function from a library like eases is super-easy though.

var Animation = require("anymation");
var eases = require("eases");

new Animation({
   object: someObject,
   easing: eases.elasticOut
});

API

Animation(options)

Constructor for an Animation. Calling it with the new operator is optional. The animation starts immediately.

• options: An object specifying options:
  • object (object, required) - The object whose properties are going to get changed by the animation.
  • duration (number, optional, default=1000) - Duration for animation, in milliseconds
  • easing (function, optional, default=linear) - Easing function for the animation.
  • setter (function, optional) - Function called to change a property value. Signature (object, propertyName, value. The default function sets object[propertyName] = value.
  • onComplete (function, optional) -Function called when the animation completes
  • onCancel (function, optional) - Function called when the animation is canceled

Animation.tween(propertyName, from, to) returns this Animation

Smoothly change a numeric property between the start and end values. Shortcut for Animation.addProp(propertyName, { tween: [from, to] }).

• propertyName (string) - Name of the property on the object
• start (number) - Starting value
• end (number) - Ending value

Animation.discrete(propertyName, array) returns this Animation

Cycle a property through a specified list of values (of any type) over the course of the animation. Shortcut for Animation.addProp(propertyName, { discreteValues: array }).

• propertyName (string) - Name of the property on the object
• array (array) - Specified values

Animation.fn(propertyName, fn) returns this Animation

Animate a property using a callback function returning a value of any type. Shortcut for Animation.addProp(propertyName, { valueFn: fn});

• propertyName (string) - Name of the property on the object
• fn (function) - a function with signature fn(t_eased) returns value, where t_eased is the eased current time. With linear easing this is 0 at the start of the animation and 1 at the end, increasing linearly in between. In general it is 0 at the start and 1 at the end, with no promises it can't be negative or greater than one in-between (in elastic easing functions for example). The function should return the desired value for the property at the given eased time.

Animation.addProp(propertyName, options) returns this Animation

Animates a property during the course of the animation, specifying all options, many of which can override the animation's default options.

• propertyName (string) - Name of the property on the object

• options (object):

  • object (object, optional, default=this.options.object) - The object whose property is to be changed.
  • easing (function, optional, default=this.options.easing) - Easing function for this property.
  • setter (function, optional, default=this.options.setter) - Function called to change this property value. Signature (object, propertyName, value. The default function sets object[propertyName] = value.
  • tween (array[number], optional) - see Animation.tween()
  • discreteValues (array, optional) - see Animation.discrete()
  • valueFn (function, optional) - see Animation.fn()

  Animation.update(timeNow) returns boolean

  Updates all animated properties. Generally no need to pass the timeNow parameter.

  • timeNow (number, optional, default=current system time in milliseconds)

  Returns false if the animation is done (if timeNow >= the animation start time + the animation duration) otherwise true