         * Draws a scaled-down occlusion on _occlusionLoResBmd and erases it from _baseBmd.
         */
         protected function _eraseLoResOcclusion():void {
-            _occlusionLoResBmd.fillRect(_occlusionLoResBmd.rect, 0);
+            _occlusionLoResBmd.fillRect(_bufferRect, 0);
             _copyMatrix(_occlusion.transform.matrix, _mtx);
             _mtx.scale(_bufferWidth / _viewportWidth, _bufferHeight / _viewportHeight);
             _occlusionLoResBmd.draw(_occlusion, _mtx);

            _bufferBmd         = new BitmapData(_bufferWidth, _bufferHeight, false, 0);
            _occlusionLoResBmd = new BitmapData(_bufferWidth, _bufferHeight, true, 0);
            _occlusionLoResBmp = new Bitmap(_occlusionLoResBmd);
        }

        /**

        protected var _bufferSize:uint = 0x8000;
        protected var _bufferWidth:uint;
        protected var _bufferHeight:uint;
        protected var _bufferRect:Rectangle = new Rectangle;
        protected var _viewportWidth:uint;
        protected var _viewportHeight:uint;
        protected var _mtx:Matrix = new Matrix;
        protected var _zero:Point = new Point;

        /**
        * Creates a new effect container.
