virtual void paint(QPainter &p, const QRect &rect, double scale,
double offset) = 0;
+ /**
+ * Computes the outline rectangle of a label.
+ * @param p the QPainter to lay out text with.
+ * @param rect The rectangle of the signal header.
+ * @return Returns the rectangle of the signal label.
+ */
+ virtual QRectF get_label_rect(QPainter &p, const QRect &rect);
+
/**
* Paints the signal label into a QGLWidget.
* @param p the QPainter to paint into.