diff --git a/plot.h b/plot.h
--- a/plot.h
+++ b/plot.h
@@ -22,7 +22,9 @@
 
 #include <qwt_plot.h>
 #include <qwt_plot_grid.h>
+#include <qwt_plot_shapeitem.h>
 #include "zoomer.h"
+#include "scalezoomer.h"
 
 class Plot : public QwtPlot
 {
@@ -36,7 +38,9 @@ private:
     bool isAutoScaled;
     double yMin, yMax;
     Zoomer zoomer;
+    ScaleZoomer sZoomer;
     QwtPlotGrid grid;
+    QwtPlotShapeItem rectItem;
 
     void resetAxes();