Method pingPong

plugins/tweenSystem.js:142–147

Like `loop`, but swap `start` and `end` between iterations so the value * bounces back and forth. `pingPong()` with no argument bounces forever. * * Mutually exclusive with `loop`; calling either replaces the other, and * calling `then` after either clears the loop (last call

(count = Infinity)

     *  @returns {Tween}
     *  @memberof TweenSystem */
    pingPong(count = Infinity)
    {
        this.loopRemaining = count;
        this.thenCallback = () => pingPongContinuation(this);
        return this;
    }

    /** Pause this tween. While paused, tweenUpdate skips it.
     *  @memberof TweenSystem */