 		 */
 		public function Viewport(width			: uint		= 0,
 								 height			: uint		= 0,
-								 autoResize		: Boolean	= false,
 								 antiAliasing	: int		= 0,
 								 rendererType	: Class 	= null)
 		{
 			this.width = width;
 			this.height = height;
 			
-			_autoResize = autoResize;
-			_aa = antiAliasing;
+			_autoResize = _width == 0 || _height == 0;
+			_antiAliasing = antiAliasing;
 			_rendererClass = rendererType || DirectRenderer;
 			
 			addEventListener(Event.ADDED_TO_STAGE, addedToStageHandler);

			if (_stage3d)
			{
				updateRectangle();
				_stage3d.context3D.configureBackBuffer(_width, _height, _aa, true);
				
				_renderer = new DirectRenderer(this, _stage3d.context3D);
				

			
			if (_autoResize)
			{
				stage.align = StageAlign.TOP_LEFT;
				stage.scaleMode = StageScaleMode.NO_SCALE;
				stage.addEventListener(Event.RESIZE, stageResizeHandler);
				
				width = stage.stageWidth;
