code: function ( options ) {
              // baseAngle ----------
              this._baseAngle = options.baseAngle? this._correctDegree( options.baseAngle ) : 0;
              this._resetOptions( options );
      
              //point
              var center = this._centerPoint,
                  point = this._getPoint( this._baseAngle, center );
      
              this._pageX = point.x;
              this._pageY = point.y;
              this._pointX = point.x;
              this._pointY = point.y;
              this._centerX = center.x;
              this._centerY = center.y;
      
              // touch-action ----------
              if ( navigator.pointerEnabled ) {
                  this._msTouchAction = 'touch-action';
              } else if ( navigator.msPointerEnabled ) {
                  this._msTouchAction = '-ms-touch-action';
              }
          }
docs: ===============	Private Methods =============== //