/**
     * Set the play mode.
     * If the animation is played, it will continue playing at least once more, depending on the new play mode set.
     * If the animation is not set, the will be initialized and will wait for the user to start playing it.
     */
    public set playMode(value: AnimationPlayMode) {
        if (value === this._playMode) {
            return;
        }

        this._playMode = value;

        if (this.state === AnimationState.PLAYING) {
            this._animationGroup.play(this._playMode === AnimationPlayMode.LOOP);
        } else {
            this._animationGroup.reset();
            this._state = AnimationState.INIT;
        }
    }

 /**
  * Restart the animation group
  */
 restart() {
     if (this.state === AnimationState.PAUSED) {
         this._animationGroup.restart();
     }
     else {
         this.start();
     }
 }

 /**
  * Dispose this animation object.
  */
 public dispose() {
     this._animationGroup.dispose();
 }

 /**
  * Stop the animation.
  * This will fail silently if the animation group is already stopped.
  */
 public stop() {
     this._animationGroup.stop();
     if (!this._animationGroup.isStarted) {
         this._state = AnimationState.STOPPED;
     }
 }

 /**
  * Pause the animation
  */
 pause() {
     this._animationGroup.pause();
     this._state = AnimationState.PAUSED;
 }

 /**
  * Start playing the animation.
  */
 public start() {
     this._animationGroup.start(this.playMode === AnimationPlayMode.LOOP, this.speedRatio);
     if (this._animationGroup.isStarted) {
         this._state = AnimationState.PLAYING;
     }
 }

 /**
  *
  * @param frameNumber Go to a specific frame in the animation
  */
 goToFrame(frameNumber: number) {
     this._animationGroup.goToFrame(frameNumber + this._animationGroup.from);
 }

 /**
  * Reset the animation group
  */
 reset() {
     this._animationGroup.reset();
 }

 restart() {
     this._animationGroup.restart();
 }