Add a View resize notification function called from WindowResizeHandler

include/vsg/app/View.h

@@ -86,6 +86,9 @@ namespace vsg
         /// override states for customization of graphics pipelines for this view
         GraphicsPipelineStates overridePipelineStates;
 
+        // abstract class to notify that the window is resized
+        virtual void resize() {};
+
     protected:
         virtual ~View();
     };

src/vsg/app/WindowResizeHandler.cpp

@@ -183,4 +183,7 @@ void WindowResizeHandler::apply(vsg::View& view)
     view.traverse(*this);
 
     context->defaultPipelineStates.pop_back();
+
+    // Notify the view about the resize
+    view.resize();
 }