#include <list>
+#include <QMouseEvent>
#include <QPen>
#include <QPoint>
virtual void hover_point_changed(const QPoint &hp);
+ /**
+ * Handles left mouse button press events.
+ * @param event the mouse event that triggered this handler.
+ */
+ virtual void mouse_left_press_event(const QMouseEvent* event);
+
protected:
static QPen highlight_pen();