Choreo.js is a lightweight helper for the Web Animations Javascript API, that allows you to:

• Choreograph scenes of animation on one or more elements
• Set animation intervals on a group of elements to get smooth sequential effects
• Trigger animation scenes based on whether the elements are in or partially in the viewport
• Provides a small animation library, with the option to create your own

Before you get creating slick animation sequences with Choreo.js

It's important to remember that the Web Animation API is not quite fully supported by all browsers. Choreo has a dependency on the web-animation-next polyfill to solve that. Make sure you include it before executing scenes:

https://cdnjs.cloudflare.com/ajax/libs/web-animations/2.2.2/web-animations-next.min.js

Usage

Install using npm: $ npm install choreo.js --save-dev

Create as many scenes as you like using the createScene method, as shown below:

import createScene from 'choreo.js';

createScene({
  sceneDelay: 300,                          
  elements: ['.element', '.element2'],     
  animationType: 'fadeUpIn',               
  interval: 50,                            
  trigger: 'onlyWhenInView'                                                  
})

Configuration Options

• sceneDelay: Scene delay (ms) sets a global animation delay by overriding the animations delay (specified in animationType)
• elements: Pass in an array of classes as strings, in order that you'd like them to execute
• animationType: Either use the built in animations by passing in string names, or define your own animation objects like this:

let fadeUpIn = {
  keyframes: [
    { transform: 'translateY(-100%)', opacity: 0 },
    { transform: 'translateY(0)', opacity: 1 }
  ],
  timing: {
      duration: 500,
      delay: 0, // This is overridden by sceneDelay in your createScene object
      easing: 'cubic-bezier(.4,0,0,1)',
      fill: 'both'
  }
}

Read up on the Web Animation API documentation for more specific information on defining custom keyframes & timing.

• interval: Defines the delay between each element animating to get smooth sequential motion effects
• trigger: Takes either 'onlyWhenInView' or 'onlyWhenInPartialView' - These allow animation to be triggered when the element is either fully in the viewport or partially shown.

Example

Roadmap

If I get the time, these are a few pointers for the roadmap:

• Allow elements in a scene to take their own animationType
• Provide an executeScene() method to wrap scenes and pass triggers or mouse events/other interactions

License

MIT © Sam Lillicrap