Generate wxDPIChangedEvent when DPI changes

interface/wx/event.h

@@ -3318,6 +3318,62 @@ public:
 };
 
 
+
+/**
+    @class wxDPIChangedEvent
+
+    Event sent when the resolution (measured in dots-per-inch, or DPI) of the
+    monitor a window is on changes.
+
+    The event is sent to each wxTopLevelWindow affected by the change, and all
+    its children recursively. For example, this event is sent to the window
+    when it is moved, by the user, from a display using some DPI value to
+    another display using a different DPI value. It also sent to all program
+    windows on the given display if its DPI changes due to a change in the
+    system settings.
+
+    Currently this event is generated by wxMSW port if only and only if the
+    MSW application runs under Windows 10 Creators Update (v1703) or later and
+    is marked as being "per-monitor DPI aware", i.e. contains a @c dpiAwareness
+    tag with the value "PerMonitorV2" in its manifest (see Microsoft
+    <a href="https://docs.microsoft.com/en-us/windows/desktop/sbscs/application-manifests">"Application Manifests" documentation</a>
+    for more details).
+
+    @note Per-monitor DPI support is an experimental feature that is still in
+    development. It might not work correctly for some controls.
+
+    @beginEventTable{wxDPIChangedEvent}
+    @event{EVT_DPI_CHANGED(func)}
+        Process a @c wxEVT_DPI_CHANGED event.
+    @endEventTable
+
+    @since 3.1.3
+
+    @library{wxcore}
+    @category{events}
+
+    @see @ref overview_events
+*/
+class wxDPIChangedEvent : public wxEvent
+{
+public:
+    /**
+        Returns the old DPI.
+
+        @since 3.1.3
+    */
+    wxSize GetOldDPI() const;
+
+    /**
+        Returns the new DPI.
+
+        @since 3.1.3
+    */
+    wxSize GetNewDPI() const;
+};
+
+
+
 class wxPaletteChangedEvent : public wxEvent
 {
 public: