# ModelAnimation

#### new Cesium.ModelAnimation()
Scene/ModelAnimation.js 23

An active glTF animation. A glTF asset can contain animations. An active animation is an animation that is currently playing or scheduled to be played because it was added to a model's `ModelAnimationCollection`. An active animation is an instance of an animation; for example, there can be multiple active animations for the same glTF animation, each with a different start time.

Create this by calling `ModelAnimationCollection#add`.

##### See:

- ModelAnimationCollection#add

### Members

#### readonly delay : Number
Scene/ModelAnimation.js 158

The delay, in seconds, from `ModelAnimation#startTime` to start playing.

Default Value: `undefined`

#### readonly loop : ModelAnimationLoop
Scene/ModelAnimation.js 227

Determines if and how the animation is looped.

Default Value: ``ModelAnimationLoop.NONE``

#### readonly multiplier : Number
Scene/ModelAnimation.js 195

Values greater than `1.0` increase the speed that the animation is played relative to the scene clock speed; values less than `1.0` decrease the speed. A value of `1.0` plays the animation at the speed in the glTF animation mapped to the scene clock speed. For example, if the scene is played at 2x real-time, a two-second glTF animation will play in one second even if `multiplier` is `1.0`.

Default Value: `1.0`

#### readonly name : String
Scene/ModelAnimation.js 125

The glTF animation name that identifies this animation.

#### removeOnStop : Boolean
Scene/ModelAnimation.js 37

When `true`, the animation is removed after it stops playing. This is slightly more efficient that not removing it, but if, for example, time is reversed, the animation is not played again.

Default Value: `false`

#### readonly reverse : Boolean
Scene/ModelAnimation.js 211

When `true`, the animation is played in reverse.

Default Value: `false`

#### start : Event
Scene/ModelAnimation.js 57

The event fired when this animation is started. This can be used, for example, to play a sound or start a particle system, when the animation starts.

This event is fired at the end of the frame after the scene is rendered.

Default Value: `new Event()`

##### Example:

    animation.start.addEventListener(function(model, animation) {
      console.log('Animation started: ' + animation.name);
    });

#### readonly startTime : JulianDate
Scene/ModelAnimation.js 142

The scene time to start playing this animation. When this is `undefined`, the animation starts at the next frame.

Default Value: `undefined`

#### stop : Event
Scene/ModelAnimation.js 93

The event fired when this animation is stopped. This can be used, for example, to play a sound or start a particle system, when the animation stops.

This event is fired at the end of the frame after the scene is rendered.

Default Value: `new Event()`

##### Example:

    animation.stop.addEventListener(function(model, animation) {
      console.log('Animation stopped: ' + animation.name);
    });

#### readonly stopTime : JulianDate
Scene/ModelAnimation.js 176

The scene time to stop playing this animation. When this is `undefined`, the animation is played for its full duration and perhaps repeated depending on `ModelAnimation#loop`.

Default Value: `undefined`

#### update : Event
Scene/ModelAnimation.js 76

The event fired when on each frame when this animation is updated. The current time of the animation, relative to the glTF animation time span, is passed to the event, which allows, for example, starting new animations at a specific time relative to a playing animation.

This event is fired at the end of the frame after the scene is rendered.

Default Value: `new Event()`

##### Example:

    animation.update.addEventListener(function(model, animation, time) {
      console.log('Animation updated: ' + animation.name + '. glTF animation time: ' + time);
    });