Keyframe Formats

There are two different ways to format keyframes:

1. An object containing key-value pairs consisting of the property to animate and an array of values to iterate over.

   JavaScript

   Copy Code

   element.animate({
     opacity: [ 0, 1 ],          // [ from, to ]
     color:   [ "#fff", "#000" ] // [ from, to ]
   }, 2000);

2. An array of objects (keyframes) consisting of properties and values to iterate over. This is the canonical format returned by the getKeyframes() method.

   JavaScript

   Copy Code

   element.animate([ 
     { // from
       opacity: 0,
       color: "#fff"
     }, 
     { // to
       opacity: 1,
    ​   color: "#000"
     }
   ], 2000);

   With this latter form it is also possible to specify offsets for each keyframe by providing an offset value.

   JavaScript

   Copy Code

   element.animate([ { opacity: 1 },
                     { opacity: 0.1, offset: 0.7 },
                     { opacity: 0 } ],
                   2000);

   Note: offset values, if provided, must be between 0.0 and 1.0 and arranged in ascending order.

   Furthermore, using this form it is also possible to specify easing to apply between keyframes by providing an easing value as illustrated below.

   JavaScript

   Copy Code

   element.animate([ { opacity: 1, easing: 'ease-out' },
                     { opacity: 0.1, easing: 'ease-in' },
                     { opacity: 0 } ],
                   2000);

   In this example, the specified easing only applies from the keyframe where it is specified until the next keyframe. Any easing value specified on the options argument, however, applies across a single iteration of the animation — for the entire duration.