Remove extra qualifier from trackballPoint

QTProject/mainwidget.h

@@ -43,7 +43,7 @@ protected:
         void wheelEvent(QWheelEvent *event ) ;
 
 private:
-        QVector3D* MainWidget::trackballPoint(int x, int y);
+        QVector3D* trackballPoint(int x, int y);
         void rotate(QVector3D *newPos );
         void move(QPointF *newPos );