1    package npw;
2    /* 
3     * A program to paint, centered on the canvas, a circle of randomly colored circles 
4     * In this program, we will add spaces between each circle 
5     */
6    
7    import painter.SPainter;
8    import shapes.SCircle;
9    import shapes.SSquare;
10   import javax.swing.*;
11   import java.awt.*;
12   import java.util.Random;
13   import java.util.Scanner;
14   public class HirstDots {
15       private void paintTheImage(){
16           // Get the input info
17           int bigRadius = getNumber("Overall circle radius");
18           int individualRadius = getNumber("Individual circle radius");
19   
20           // Establish a painter
21           SPainter painter = new SPainter("Circle of circles", bigRadius*2+50, bigRadius*2+50);
22           painter.setBrushWidth(3);
23           SCircle totalCircle = new SCircle(bigRadius);
24           SCircle individualCircle = new SCircle(individualRadius);
25   
26           // Paint the squares
27           paintHirstDots(painter, totalCircle, individualCircle);
28       }
29   
30       private void paintHirstDots(SPainter painter, SCircle bCircle, SCircle iCircle){
31           // Position the painter to begin drawing rows
32           painter.mfd(bCircle.radius());
33           painter.tr();
34           // Paint the circle of squares
35           double moved = 0;
36           while (moved < bCircle.diameter()) {
37               double chord = chordLength(bCircle.radius() - moved, bCircle);
38               int squares = squaresOnLineCount(chord, iCircle.diameter());
39               paintRow(painter, iCircle, squares);
40               nextRow(painter, iCircle.diameter());
41               moved = moved + iCircle.diameter();
42           }
43           // Invariance
44           painter.tl();
45           painter.mfd(bCircle.radius());
46       }
47   
48       // Move to next row
49       private void nextRow(SPainter painter, double rowHeight){
50           painter.tr();
51           painter.mfd(rowHeight);
52           painter.tl();
53       }
54   
55       // Assumes the painter is at the center of the row to paint, facing right.
56       private void paintRow(SPainter painter, SCircle iCircle, int squaresToPaint){
57           // Move backward 1/2 of the length we're painting to get ready to paint the row.
58           double centerOffset = ( (squaresToPaint * iCircle.diameter()) / 2) - iCircle.diameter()/2;
59           painter.mbk(centerOffset);
60   
61           // Paint the row of circles.
62           int painted = 0;
63           while (painted < squaresToPaint){
64               paintOneCircle(painter, iCircle);
65               painter.mfd(iCircle.diameter());
66               painted = painted + 1;
67           }
68   
69           // Make the method invariant w/ respect to painter position.
70           painter.mbk(centerOffset + iCircle.diameter());
71       }
72   
73       private void paintOneCircle(SPainter painter, SCircle iCircle){
74           iCircle.s2();
75           painter.setColor(randomColor());
76           painter.paint(iCircle);
77           //Remove black outline from circles
78           //painter.setColor(Color.BLACK);
79           //painter.draw(iCircle);
80           iCircle.x2();
81       }
82   
83       private static int squaresOnLineCount(double lineLength, double sideLength){
84           int circles = ( (int)Math.ceil( ( lineLength - sideLength ) / sideLength ) + 1);
85           return circles;
86       }
87   
88       private double chordLength(double yOffset, SCircle circle){
89           double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2));
90           double chordLength = xLength * 2;
91           return chordLength;
92       }
93   
94       private static int getNumber(String prompt) {
95           String nss = JOptionPane.showInputDialog(null,prompt+"?");
96           Scanner scanner = new Scanner(nss);
97           return scanner.nextInt();
98       }
99   
100      private static Color randomColor() {
101          Random rgen = new Random();
102          int r = rgen.nextInt(256);
103          int g = rgen.nextInt(256);
104          int b = rgen.nextInt(256);
105          return new Color(r,g,b);
106      }
107  
108      public HirstDots() {
109          paintTheImage();
110      }
111  
112      public static void main(String[] args) {
113          SwingUtilities.invokeLater(new Runnable() {
114              public void run() {
115                  new HirstDots();
116              }
117          });
118      }
119  }
120