code: @Override
      public void draw(Object object, Graphics2D graphics, DrawInfo2D info) {
  
          ShanksAgent agent = (ShanksAgent) object;
          final double width = 20;
          final double height = 20;
  
          // Draw the devices
          final int x = (int) (info.draw.x - width / 2.0);
          final int y = (int) (info.draw.y - height / 2.0);
          final int w = (int) (width);
          final int h = (int) (height);        
          graphics.setColor(Color.gray);
          graphics.fillOval(x, y, w, h);
  
          // Draw the devices ID ID
          graphics.setColor(Color.black);
          graphics.drawString(agent.getID(), x - 3, y);
  
      }
docs: /*
  (non-Javadoc)
  @see sim.portrayal.SimplePortrayal2D#draw(java.lang.Object, java.awt.Graphics2D, sim.portrayal.DrawInfo2D)