text: #ifndef CUSTOMWIDGET_H
  #define CUSTOMWIDGET_H
  
  #include <QObject>
  #include <QWidget>
  
  class Hierarchy;
  
  class SceneWidget : public QWidget
  {
      Q_OBJECT
  public:
      explicit SceneWidget(QWidget *parent = nullptr);
  
      QSize sizeHint() const override;
      QSize minimumSizeHint() const override;
  
  
  signals:
  
  public slots:
  
  private:
      void paintEvent(QPaintEvent* event) override;
  public:
      Hierarchy* hierarchyRef = nullptr;
  };
  
  extern SceneWidget* sceneWidget;
  #endif // CUSTOMWIDGET_H
  