disable 'use pixmap caching' by hiding it's checkbox and it's appsetting return false;

oscar/SleepLib/appsettings.h

@@ -129,7 +129,7 @@ public:
   //! \brief Returns true if Graphical animations & Transitions will be drawn
   bool animations() const { return m_animations; }
   //! \brief Returns true if PixmapCaching acceleration will be used
-  inline bool usePixmapCaching() const { return m_usePixmapCaching; }
+  inline bool usePixmapCaching() const { return /*m_usePixmapCaching*/false; } //disables use pixmap caching without modifing any code.
   //! \brief Returns true if Square Wave plots are preferred (where possible)
   inline bool squareWavePlots() const { return m_squareWavePlots; }
   //! \brief Whether to allow double clicking on Y-Axis labels to change vertical scaling mode

oscar/preferencesdialog.ui

@@ -2835,6 +2835,9 @@ Try it and see if you like it.</string>
                  <property name="text">
                   <string>Use Pixmap Caching</string>
                  </property>
+                 <property name="visible" stdset="0">
+                  <bool>false</bool>
+                 </property>
                 </widget>
                </item>
                <item>