question: private void renderOperatorBackground ( final Operator operator , final Graphics2D g2 ) { Rectangle2D frame = model . getOperatorRect ( operator ) ; if ( frame == null ) { return ; } RoundRectangle2D background = new RoundRectangle2D . Double ( frame . getX ( ) - 7 , frame . getY ( ) - 3 , frame . getWidth ( ) + 14 , frame . getHeight ( ) + 11 , OPERATOR_BG_CORNER , OPERATOR_BG_CORNER ) ; g2 . setColor ( Color . WHITE ) ; g2 . fill ( background ) ; Rectangle2D nameBounds = OPERATOR_FONT . getStringBounds ( operator . getName ( ) , g2 . getFontRenderContext ( ) ) ; if ( nameBounds . getWidth ( ) > frame . getWidth ( ) ) { double relevantWidth = Math . min ( nameBounds . getWidth ( ) , frame . getWidth ( ) * MAX_HEADER_RATIO ) ; double offset = ( frame . getWidth ( ) - relevantWidth ) / 2 ; int x = ( int ) ( frame . getX ( ) + offset ) ; int padding = 5 ; RoundRectangle2D nameBackground = new RoundRectangle2D . Double ( ( int ) Math . min ( frame . getX ( ) - padding , x - padding ) , frame . getY ( ) - 3 , relevantWidth + 2 * padding , ProcessRendererModel . HEADER_HEIGHT + 3 , OPERATOR_BG_CORNER , OPERATOR_BG_CORNER ) ; g2 . fill ( nameBackground ) ; } renderPortsBackground ( operator . getInputPorts ( ) , g2 ) ; renderPortsBackground ( operator . getOutputPorts ( ) , g2 ) ; }
target:  Draws the operator background (white round rectangle).