float epsilon = (float) 0.5;
Rectangle2D r = new Rectangle2D(new Vector2D(0 - epsilon, 0 - epsilon), new Vector2D(width - epsilon, height - epsilon));
LineSegment2D l = new LineSegment2D(new Vector2D(0 - epsilon, heightGO + epsilon), new Vector2D(this.getWidth() - epsilon, heightGO + epsilon));
g.setColor(Color.red);
g.drawPolygon(this.getPolygonInVisualization(l.toPol2D()).toPol());
g.setStroke(new BasicStroke(5));
g.setColor(Color.orange);
g.drawPolygon(this.getPolygonInVisualization(r.toPol2D()).toPol());
g.setColor(Color.black);