Цикл отказывается работать - Java

Формулировка задачи:

Добрый день! Пишу домашку по информатике, и тут - сюрприз! Не работает внешний цикл при наличии внутреннего! Как он зафиксирует 'x = -10.0' так этот x никуда и не сдвинется, а цикл завершится по завершении внутреннего. Вот код:

package fractals;
 
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.geom.*;
 
public class MainFrame extends javax.swing.JFrame {
 
    private Point2D.Double centerPoint;
    private double scale;
 
    private double a, b, c;
    private double infinity;
    private int maxCoubtOfSteps;
 
    public MainFrame() {
        initComponents();
        centerPoint = new Point2D.Double(0, 0);
        scale = 20;
    }
 
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {
 
        jPanel1 = new javax.swing.JPanel();
 
        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
 
        jPanel1.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
                jPanel1MouseClicked(evt);
            }
        });
 
        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 400, Short.MAX_VALUE)
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 300, Short.MAX_VALUE)
        );
 
        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
        );
 
        pack();
    }// </editor-fold>                        
 
    private void jPanel1MouseClicked(java.awt.event.MouseEvent evt) {                                     
        paintToPanel();
    }                                    
 
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see [url]http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html[/url] 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(MainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>
 
        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new MainFrame().setVisible(true);
            }
        });
    }
 
    private Color colorFunc(int step) {
        return new Color(step);
    }
 
    private Point toScreenPoint(Complex c) {
        int w = jPanel1.getWidth();
        int h = jPanel1.getHeight();
        return new Point(w / 2 + (int) ((w / scale) * (c.a - centerPoint.x)),
                h / 2 + (int) ((w / scale) * (c.b - centerPoint.y)));
    }
 
    private void paintToPanel() {
        Graphics p1g = jPanel1.getGraphics();
        double w = jPanel1.getWidth() * 1.0;
        double h = jPanel1.getHeight() * 1.0;
        double x = centerPoint.x - (scale / 2.0);
        double lx = centerPoint.x + (scale / 2.0);
        double y = centerPoint.y - (h / w) * (scale / 2.0);
        double ly = centerPoint.y + (h / w) * (scale / 2.0);
        double step = scale / (w * 1.0);
 
        MyFunction mf = new MyFunction(a, b, c);
        System.out.println(x + " " + lx);
 
        for (; x <= lx; x += step) {
            for (; y <= ly; y += step) {
                Worker worker = new Worker(mf,
                        new Worker.Completed() {
 
                            @Override
                            public void completed(Complex p, int step) {
                                Point sp = toScreenPoint(p);
                                p1g.setColor(colorFunc(step));
                                p1g.fillRect(sp.x, sp.y, 1, 1);
                            }
                        },
                        new Complex(x, y),
                        maxCoubtOfSteps,
                        infinity);
                worker.start();
                System.out.println(x + " " + y);
            }
        }
    }
 
    @Override
    public void paint(Graphics g) {
        super.paint(g);
 
        a = b = c = 1;
        infinity = 1;
        maxCoubtOfSteps = 10;
 
        System.out.println("paint");
        paintToPanel();
    }
 
    // Variables declaration - do not modify                     
    private javax.swing.JPanel jPanel1;
    // End of variables declaration                   
}

Более того, если написать ЛЮБОЙ вложенный цикл в методе paint(), то внешний не будет работать. Поэтому я вынес это всё в paintToPanel(). Но и это не помогло. И только цикл, написанный в main(), будет работать, так, как положено ему работать. Буду очень признателен

Решение задачи: «Цикл отказывается работать»

textual
                            Листинг программы 
                        

                            package fractals;
 
public class Worker extends Thread{
 
    private final Function f;
    private final Completed c;
    private final int maxCountOfSteps;
    private final double infinity;
    private final Complex p;
    
    public static interface Completed{
        public void completed(Complex p, int step);
    }
    
    public Worker(Function f, Completed c, Complex p, int maxCountOfSteps, double infinity){
        this.f = f;
        this.c = c;
        this.p = p;
        this.maxCountOfSteps = maxCountOfSteps;
        this.infinity = infinity;
    }
    
    @Override
    public void run() {
        Complex cur = new Complex(p.a, p.b);
        for(int i = 1; i <= maxCountOfSteps; ++i){
            cur = f.f(cur);
            if(cur.moodle() >= infinity){
                c.completed(p, i);
                interrupt();
            }
        }
    }
    
}
                        