1    /* 
2     * A program to paint, centered on the canvas, a circle of randomly colored, black-framed squares. 
3     */
4    
5    package npw;
6    
7    import painter.SPainter;
8    import shapes.SCircle;
9    
10   import javax.swing.*;
11   import java.awt.*;
12   import java.util.Random;
13   import java.util.Scanner;
14   
15   public class HirstDots {
16       private void paintTheImage() {
17           // get input
18           int radius = getNumber("circle radius");
19           int side = getNumber("circle radius");
20   
21           // Establish the painter
22           SPainter painter = new SPainter("Circle of Squares", radius*2+50, radius*2+50);
23           painter.setBrushWidth(3);
24           SCircle bigCircle = new SCircle(radius);
25           SCircle littleCircle = new SCircle(side);
26   
27           // paint the squares
28           paintCircleOfSquares(painter, bigCircle, littleCircle);
29       }
30   
31       private void paintCircleOfSquares(SPainter painter, SCircle bigCircle, SCircle littleCircle) {
32           // position the painter to begin drawing the rows
33           painter.mfd(bigCircle.radius());
34           painter.tr();
35           // paint the circle of squares
36           double moved = 0;
37           while ( moved < bigCircle.diameter() ) {
38               double chord = chordLength(bigCircle.radius() - moved, bigCircle);
39               int squares = squaresOnLineCount(chord, littleCircle.radius()*2);
40               paintRow(painter, littleCircle, squares);
41               nextRow(painter, littleCircle.radius()*2);
42               moved = moved + littleCircle.radius()*2;
43           }
44           // make the method with respect to painter position
45           painter.tl();
46           painter.mfd(bigCircle.radius());
47       }
48   
49       // Move to the next row
50       private void nextRow(SPainter painter, double rowHeight) {
51           painter.tr();
52           painter.mfd(rowHeight);
53           painter.tl();
54       }
55   
56       // Assumes the painter is at the center of the row to paint, facing right.
57       private void paintRow(SPainter painter, SCircle circle, int squaresToPaint) {
58   
59           // Move backward 1/2 of the length in respect to painting to get ready to paint row.
60           double centerOffSet = ( (squaresToPaint * circle.radius()) - circle.radius());
61           painter.mbk(centerOffSet);
62   
63           // Paint the row of squares.
64           int painted = 0;
65           while ( painted < squaresToPaint ) {
66               paintOneSquare(painter, circle);
67               painter.mfd(circle.radius()*2);
68               painted = painted + 1;
69           }
70           // Make the method in respect to painted position.
71           painter.mbk(centerOffSet + circle.radius()*2);
72       }
73   
74       private void paintOneSquare(SPainter painter, SCircle circle) {
75           painter.setColor(randomColor());
76           circle.s2();
77           painter.paint(circle);
78   
79           circle.x2();
80       }
81   
82       private static int squaresOnLineCount(double lineLength, double sideLength) {
83           int circle = ( (int)Math.ceil(( lineLength - sideLength) / sideLength)+1);
84           return circle;
85       }
86   
87       private double chordLength(double yOffset, SCircle circle) {
88           double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2));
89           double chordLength = xLength * 2;
90           return chordLength;
91       }
92   
93       public static int getNumber(String prompt) {
94           String nss = JOptionPane.showInputDialog(null, prompt+"?");
95           Scanner scanner = new Scanner(nss);
96           return scanner.nextInt();
97       }
98   
99       public static Color randomColor() {
100          Random rgen = new Random();
101          int r = rgen.nextInt(256);
102          int g = rgen.nextInt(256);
103          int b = rgen.nextInt(256);
104          return new Color(r,g,b);
105      }
106  
107      public HirstDots() {
108          paintTheImage();
109      }
110  
111      public static void main(String[] args) {
112          SwingUtilities.invokeLater(new Runnable() {
113              public void run() {
114                  new HirstDots();
115              }
116          });
117      }
118  }
119