| That's not what Windowed3D() is for.  It is to check if the display hardware is capable of 3D in a window, not if the game is in windowed mode.  Since you set the fullscreen/windowed mode yourself when you call Graphics/Graphics3D telling which mode you are in should be easy.  I just declare a global "screenmode" variable at the top and change that, using it when I call Graphics (as in Graphics xres,yres,clrdepth,screenmode all using global variables;) if/when I need to know the screenmode I just check that variable. 
 
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