1    package npw;
2    import painter.SPainter;
3    import shapes.SCircle;
4    import javax.swing.*;
5    import java.awt.*;
6    import java.util.Random;
7    import java.util.Scanner;
8    public class HirstDots
9    {
10       private void paintTheImage()
11       {
12           int radius = getNumber("circle radius");
13           int altRadius = getNumber("small circle radius");
14           SPainter painter = new SPainter("Hirst Dots", radius*2+50, radius*2+50);
15           painter.setBrushWidth(3);
16           SCircle circle = new SCircle(radius);
17           SCircle altCircle = new SCircle(altRadius);
18           paintHirstSquares(painter, circle, altCircle);
19       }
20       private void paintHirstSquares(SPainter painter, SCircle circle, SCircle altCircle)
21       {
22           painter.mfd(circle.radius());
23           painter.tr();
24           double moved = 0;
25           while (moved < circle.diameter())
26           {
27               double chord = chordLength(circle.radius() - moved, circle);
28               int circles = circlesOnLineCount(chord, altCircle.radius());
29               paintRow(painter, altCircle, circles);
30               nextRow(painter, altCircle.radius());
31               moved = moved + altCircle.radius();
32           }
33           painter.tl();
34           painter.mfd(circle.radius());
35       }
36       private void nextRow(SPainter painter, double rowHeight){
37           painter.tr();
38           painter.mfd(rowHeight);
39           painter.tl();
40       }
41       private void paintRow(SPainter painter, SCircle altCircle, int circlesToPaint)
42       {
43           double centerOffset = ( (circlesToPaint * altCircle.radius()) / 2) - altCircle.radius()/2;
44           painter.mbk(centerOffset);
45           int painted = 0;
46           while (painted < circlesToPaint)
47           {
48               paintOneSquare(painter, altCircle);
49               painter.mfd(altCircle.radius());
50               painted = painted + 1;
51           }
52           painter.mbk(centerOffset + altCircle.radius());
53       }
54       private void paintOneSquare(SPainter painter, SCircle altCircle)
55       {
56           painter.setColor(randomColor());
57           altCircle.s3();
58           painter.paint(altCircle);
59           altCircle.x3();
60       }
61       private static int circlesOnLineCount(double lineLength, double sideLength)
62       {
63           int circles = ( (int)Math.ceil( ( lineLength - sideLength ) / sideLength ) + 1);
64           return circles;
65       }
66       private double chordLength(double yOffset, SCircle circle)
67       {
68           double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2));
69           double chordLength = xLength * 2;
70           return chordLength;
71       }
72       private static int getNumber(String prompt)
73       {
74           String nss = JOptionPane.showInputDialog(null,prompt+"?");
75           Scanner scanner = new Scanner(nss);
76           return scanner.nextInt();
77       }
78       private static Color randomColor()
79       {
80           Random rgen = new Random();
81           int r = rgen.nextInt(256);
82           int g = rgen.nextInt(256);
83           int b = rgen.nextInt(256);
84           return new Color(r,g,b);
85       }
86       public HirstDots()
87       {
88           paintTheImage();
89       }
90       public static void main(String[] args)
91       {
92           SwingUtilities.invokeLater(new Runnable()
93           {
94               public void run()
95               {
96                   new HirstDots();
97               }
98           });
99       }
100  }
101