drools-eclipse/org.drools.eclipse/src/main/java/org/drools/eclipse/editors/rete/figure/VertexFigure.java
public void paint(Graphics g) {
        g.setAntialias( SWT.ON );
        Rectangle r = getBounds().getCopy();
        g.translate( r.getLocation() );
        g.setBackgroundColor( backgroundColor );
        g.setForegroundColor( borderColor );
        g.fillArc( 0,
                   0,
                   15,
                   15,
                   0,
                   360 );
        g.drawArc( 0,
                   0,
                   14,
                   14,
                   0,
                   360 );
        super.paint( g );
    }
public void paint(Graphics g) {
        g.setAntialias( SWT.ON );
        Rectangle r = getBounds().getCopy();
        g.translate( r.getLocation() );
        g.setBackgroundColor( backgroundColor );
        g.setForegroundColor( borderColor );
        g.fillArc( 0,
                   0,
                   15,
                   15,
                   0,
                   360 );
        g.drawArc( 0,
                   0,
                   14,
                   14,
                   0,
                   360 );
        super.paint( g );
    }
Painting antialiased vertex