  4
   ,        4;      .

:
-     <>,                  4.         .
-          4,        4,       .         . 
-          4,        4,    <Ctrl> + <4>  .         . 
-          4,       .
-          4,   <4>  .
-               ,       .          .    
-            2D  3D    <>   .               2D/3D  .   
-       <>    .