Etwas

package studienarbeit;import java.awt.*; import javax.swing.*;  public class N_Vertex extends JPanel {   protected void paintComponent( Graphics g )   {     //VertexDrawer.drawThickLine( 1, 1, 100, 100, 5, g);     VertexDrawer.drawThickLine( 30, 30, 200, 200, 20, g);  }    public static void main( String[] args )   {     JFrame f = new JFrame();     f.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );     f.add( new N_Vertex() );     f.setSize( 400, 400 );     f.setVisible( true );   } }  class VertexDrawer {       public static void drawThickLine( int x, int y, int x2, int y2, int thickness, Graphics g ) {        int b = Math.round( thickness /2), deltax, deltay;        double angle;                angle = Math.atan( (double)((y2-y)/(x2-x)) );        deltay = (int)Math.round( (Math.cos(angle)*b) );        deltax = (int)Math.round( (Math.sin(angle)*b) );        Polygon p = new Polygon();                p.addPoint( x-deltax, y+deltay );        p.addPoint( x+deltax, y-deltay );        p.addPoint( x2+deltax, y2-deltay );        p.addPoint( x2-deltax, y2+deltay );        g.fillPolygon( p );    }}