Method stepMutate_

src/utils/animation.js:281–319

* @param {!{[key: string]: *}} unusedState * @private

(unusedState)

   * @private
   */
  stepMutate_(unusedState) {
    if (!this.running_) {
      return;
    }
    const currentTime = Date.now();
    const normLinearTime = Math.min(
      (currentTime - this.startTime_) / this.duration_,
      1
    );

    // Start segments due to be started
    for (let i = 0; i < this.segments_.length; i++) {
      const segment = this.segments_[i];
      if (!segment.started && normLinearTime >= segment.delay) {
        segment.started = true;
      }
    }

    // Execute all pending segments.
    for (let i = 0; i < this.segments_.length; i++) {
      const segment = this.segments_[i];
      if (!segment.started || segment.completed) {
        continue;
      }
      this.mutateSegment_(segment, normLinearTime);
    }

    // Complete or start next cycle.
    if (normLinearTime == 1) {
      this.complete_(/* success */ true, /* dir */ 0);
    } else {
      if (this.vsync_.canAnimate(this.contextNode_)) {
        this.task_(this.state_);
      } else {
        dev().warn(TAG_, 'cancel animation');
        this.complete_(/* success */ false, /* dir */ 0);
      }
    }
  }

  /**
   * @param {!SegmentRuntimeDef} segment