This is a homework question and I'm having a lot of trouble with it - I've managed to do some of it but still cant finish it - can i Please get some help.

Q1. Bezier Curves

The following example allows you to interactively control a bezier curve by dragging the control points Cubic.java

Replace the call to draw the cubic shape (big.draw(cubic)), by your own function to draw a bezier by the recursive split method. Finally, add the ability to create a longer Bezier curve by adding more control points to create a second curve.

Cubic.java

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.applet.Applet;
import java.awt.geom.*;
import java.awt.image.BufferedImage;

public class Cubic extends JApplet{

    static protected JLabel label;
    CubicPanel cubicPanel;

    public void init(){
    //Initialize the layout.
        getContentPane().setLayout(new BorderLayout());
        cubicPanel = new CubicPanel();
        cubicPanel.setBackground(Color.white);
    getContentPane().add(cubicPanel);
    label = new JLabel("Drag the points to adjust the curve.");
    getContentPane().add("South", label);
    }

    public static void main(String s[]) {
        JFrame f = new JFrame("Cubic");
        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {System.exit(0);}
        });
        JApplet applet = new Cubic();
        f.getContentPane().add(applet, BorderLayout.CENTER);
        applet.init();
        f.setSize(new Dimension(350,250));
        f.setVisible(true);
    }
}

class CubicPanel extends JPanel implements MouseListener, MouseMotionListener{

    BufferedImage bi;
    Graphics2D big;
    int x, y;
    Rectangle area, startpt, endpt, onept, twopt, rect; 
    CubicCurve2D.Double cubic = new CubicCurve2D.Double();
    Point2D.Double start, end, one, two, point;
    boolean firstTime = true;
    boolean pressOut = false;

    public CubicPanel(){

        setBackground(Color.white);
                addMouseMotionListener(this);
                addMouseListener(this);

        start = new Point2D.Double();
        one = new Point2D.Double();
        two = new Point2D.Double();
        end = new Point2D.Double();

                cubic.setCurve(start, one, two, end);
        startpt = new Rectangle(0, 0, 8, 8);
        endpt = new Rectangle(0, 0, 8, 8);
        onept = new Rectangle(0, 0, 8, 8);
        twopt = new Rectangle(0, 0, 8, 8);
    }

    public void mousePressed(MouseEvent e){

        x = e.getX();
        y = e.getY();

        if(startpt.contains(x, y)){
            rect = startpt;
            point = start;
                        x = startpt.x - e.getX();
                        y = startpt.y - e.getY();
                        updateLocation(e);
        }
        else if(endpt.contains(x, y)){
            rect = endpt;
            point = end;
                        x = endpt.x - e.getX();
                        y = endpt.y - e.getY();
                        updateLocation(e);
        }
        else if(onept.contains(x, y)){
            rect = onept;
            point = one;
                        x = onept.x - e.getX();
                        y = onept.y - e.getY();
                        updateLocation(e);
        }
        else if(twopt.contains(x, y)){
            rect = twopt;
            point = two;
                        x = twopt.x - e.getX();  
                        y = twopt.y - e.getY();
                        updateLocation(e);
        } else {
            pressOut = true;
                }
    }

    public void mouseDragged(MouseEvent e){
                if(!pressOut) {
                        updateLocation(e);
        }

    }

    public void mouseReleased(MouseEvent e){
                if(startpt.contains(e.getX(), e.getY())){
                        rect = startpt;
                        point = start;
                        updateLocation(e);
                }
                else if(endpt.contains(e.getX(), e.getY())){
                        rect = endpt;
                        point = end;
                        updateLocation(e);
                }
                else if(onept.contains(e.getX(), e.getY())){
                        rect = onept;  
                        point = one;  
                        updateLocation(e);
                }
                else if(twopt.contains(e.getX(), e.getY())){
                        rect = twopt;
                        point = two;
                        updateLocation(e);
                }
                else {
                        pressOut = false;
                }
    }

    public void mouseMoved(MouseEvent e){}

    public void mouseClicked(MouseEvent e){}
    public void mouseExited(MouseEvent e){}
    public void mouseEntered(MouseEvent e){}

    public void updateLocation(MouseEvent e){

        rect.setLocation((x + e.getX())-4, (y + e.getY())-4);
        point.setLocation(x + e.getX(), y + e.getY());

                checkPoint();

        cubic.setCurve(start, one, two, end);
        repaint();
    }

    public void paintComponent(Graphics g){
                super.paintComponent(g);
        update(g);
    }

    public void update(Graphics g){

        Graphics2D g2 = (Graphics2D)g;
        Dimension dim = getSize();
        int w = dim.width;
                int h = dim.height; 

            if(firstTime){

          // Create the offsecren graphics  to render to
          bi = (BufferedImage)createImage(w, h);
          big = bi.createGraphics();

          // Get some initial positions for the control points

          start.setLocation(w/2-50, h/2);
          end.setLocation(w/2+50, h/2);
          one.setLocation((int)(start.x)+25, (int)(start.y)-25);
          two.setLocation((int)(end.x)-25, (int)(end.y)+25);

          // Set the initial positions of the squares that are
          // drawn at the control points
          startpt.setLocation((int)((start.x)-4), (int)((start.y)-4));
                  endpt.setLocation((int)((end.x)-4), (int)((end.y)-4));
                  onept.setLocation((int)((one.x)-4), (int)((one.y)-4));
                  twopt.setLocation((int)((two.x)-4), (int)((two.y)-4));

          // Initialise the CubicCurve2D
          cubic.setCurve(start, one, two, end);

          // Set some defaults for Java2D
              big.setColor(Color.black);
          big.setStroke(new BasicStroke(5.0f));
          big.setRenderingHint(RenderingHints.KEY_ANTIALIASING, 
                       RenderingHints.VALUE_ANTIALIAS_ON);
          area = new Rectangle(dim);
          firstTime = false;
        } 

        // Clears the rectangle that was previously drawn.

        big.setColor(Color.white);
        big.clearRect(0, 0, area.width, area.height);

        // Set the colour for the bezier
        big.setPaint(Color.black);

        // Replace the following line by your own function to
        // draw the bezier specified by start, one, two, end

        big.draw(cubic);

        // Draw the control points

        big.setPaint(Color.red);
        big.fill(startpt);
        big.setPaint(Color.magenta);
        big.fill(endpt);
        big.setPaint(Color.blue);
        big.fill(onept);
        big.setPaint(new Color(0, 200, 0));
        big.fill(twopt);

        // Draws the buffered image to the screen.
        g2.drawImage(bi, 0, 0, this);

    }

    /* Checks if the rectangle is contained within the applet
         * window.  If the rectangle is not contained withing the
         * applet window, it is redrawn so that it is adjacent to the
         * edge of the window and just inside the window.  */

    void checkPoint(){

        if (area == null) {
            return;
        }

        if((area.contains(rect)) && (area.contains(point))){
            return;
        }
        int new_x = rect.x;
        int new_y = rect.y;

        double new_px = point.x;
        double new_py = point.y;

        if((rect.x+rect.width)>area.getWidth()){
            new_x = (int)area.getWidth()-(rect.width-1);
        }
        if(point.x > area.getWidth()){
            new_px = (int)area.getWidth()-1;
        }
        if(rect.x < 0){  
            new_x = -1;
        }
        if(point.x < 0){
            new_px = -1;
        }
        if((rect.y+rect.width)>area.getHeight()){
            new_y = (int)area.getHeight()-(rect.height-1);
        }
        if(point.y > area.getHeight()){
            new_py = (int)area.getHeight()-1;
        }
        if(rect.y < 0){  
            new_y = -1;
        }
        if(point.y < 0){
                        new_py = -1;
                }
        rect.setLocation(new_x, new_y);
        point.setLocation(new_px, new_py);

    }
}