+ /**
+ * Computes an caches the size of the label text.
+ */
+ void compute_text_size(QPainter &p);
+
+ /**
+ * 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.
+ */
+ QRectF get_label_rect(const QRect &rect);
+
+protected: