code: function rotateDEG(angle) {
      var cx = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : undefined;
      var cy = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : undefined;
  
      return rotate(angle * PI / 180, cx, cy);
  }
docs: Calculate a rotation matrix with a DEG angle
  @param angle Angle in degree
  @param [cx] If (cx,cy) are supplied the rotate is about this point
  @param [cy] If (cx,cy) are supplied the rotate is about this point
  @returns {{a: number, b: number, c: number, e: number, d: number, f: number}} Affine matrix