pDC->SetROP2( R2_NOTXORPEN );
    CPen red;
    red.CreatePen( PS_SOLID, 1, RGB( 255, 0, 0 ) );
    pDC->SelectObject( &red );

    for( int i=0; i<100; i++)
    {
       pDC->Rectangle( 10+i, 10, 100+i, 100 );
       Sleep( 50 );
       pDC->Rectangle( 10+i, 10, 100+i, 100 );
    }
    pDC->Rectangle( 10+i, 10, 100+i, 100 );