Add OSWindow::setVisible.

util/OSWindow.h

@@ -34,6 +34,7 @@ class OSWindow
 
     virtual void setMousePosition(int x, int y) = 0;
     virtual bool resize(int width, int height) = 0;
+    virtual bool setVisible(bool isVisible) = 0;
 
   protected:
     int mWidth;

util/win32/Win32Window.cpp

@@ -493,3 +493,8 @@ bool Win32Window::resize(int width, int height)
 
     return true;
 }
+
+bool Win32Window::setVisible(bool isVisible)
+{
+    return (ShowWindow(mNativeWindow, isVisible ? SW_SHOW : SW_HIDE) == TRUE);
+}

util/win32/Win32Window.h

@@ -30,6 +30,7 @@ class Win32Window : public OSWindow
 
     void setMousePosition(int x, int y);
     bool resize(int width, int height);
+    bool setVisible(bool isVisible);
 
   private:
     std::string mClassName;