_aRenderer->GradientBackgroundOn();
_aRenderer->SetBackground( 0.33 , 0.33 , 0.33 );
_aRenderer->SetBackground2( 0.66 , 0.66 , 0.66 );
_aRenderer->GradientBackgroundOn();
_aRenderer->SetBackground( 0.33 , 0.33 , 0.33 );
_aRenderer->SetBackground2( 0.66 , 0.66 , 0.66 );