get transformMatrix() {
    //
    return {
      a: this._view.scale, // horizontal scaling
      b: 0, // vertical skewing
      c: 0, // horizontal skewing
      d: this._view.scale, // vertical scaling
      e: this._view.x,
      f: this._view.y,
    };
  }
@returns {Matrix} this coordinate system's current transformation matrix