adjustResolutionInternal(ratio, anchor) {
    const isMoving = this.getAnimating() || this.getInteracting();
    const size = this.getViewportSize_(this.getRotation());
    const newResolution = this.constraints_.resolution(
      this.targetResolution_ * ratio,
      0,
      size,
      isMoving,
    );

    if (anchor) {
      this.targetCenter_ = this.calculateCenterZoom(newResolution, anchor);
    }

    this.targetResolution_ *= ratio;
    this.applyTargetState_();
  }
Multiply the view resolution by a ratio, optionally using an anchor. Any resolution
constraint will apply.
@param {number} ratio The ratio to apply on the view resolution.
@param {import("./coordinate.js").Coordinate} [anchor] The origin of the transformation.