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 SimpleDots {
16   
17       private void paintTheImage(){
18           // Get the input information
19           int bigRadius = getNumber("circle radius");
20           int smallRadius = getNumber("circle radius");
21   
22           String colorStr = JOptionPane.showInputDialog(null, "Color of circles");
23   
24           Color color = new Color(0, 0, 0);
25   
26           if (colorStr.equalsIgnoreCase("blue")) { color = Color.BLUE; }
27           else if (colorStr.equalsIgnoreCase("red")) { color = Color.RED; }
28           else if (colorStr.equalsIgnoreCase("green")) { color = Color.GREEN; }
29           else { color = Color.BLACK; }
30   
31           System.out.println(colorStr);
32   
33           // Establish the painter
34           SPainter painter = new SPainter("Circle of Squares", bigRadius*2+50, bigRadius*2+50);
35           painter.setBrushWidth(1);
36           SCircle bigCircle = new SCircle(bigRadius);
37           SCircle smallCirlce = new  SCircle(smallRadius);
38   
39           // Paint the squares
40           paintCircleOfCirlces(painter, bigCircle, smallCirlce, color);
41       }
42   
43       private void paintCircleOfCirlces(SPainter painter, SCircle bigCircle, SCircle smallCircle, Color color){
44           // Position the painter to begin drawing the rows
45           painter.mfd(bigCircle.radius());
46           painter.tr();
47           // Paint the circle of squares
48           double moved = 0;
49           while (moved < bigCircle.diameter()) {
50               double chord = chordLength(bigCircle.radius() - moved, bigCircle);
51               int squares = squaresOnLineCount(chord, smallCircle.diameter());
52               paintRow(painter, smallCircle, squares, color);
53               nextRow(painter, smallCircle.diameter());
54               moved = moved + smallCircle.diameter();
55           }
56           // Make the method invariant with respect to painter position
57           painter.tl();
58           painter.mfd(bigCircle.radius());
59       }
60   
61       // Move to the next row
62       private void nextRow(SPainter painter, double rowHeight){
63           painter.tr();
64           painter.mfd(rowHeight);
65           painter.tl();
66       }
67   
68       // Assumes the painter is at the center of the row to paint, facing right.
69       private void paintRow(SPainter painter, SCircle circle, int squaresToPaint, Color color){
70           // Move backward 1/2 of the length we're painting to get ready to paint the row.
71           double centerOffset = ( (squaresToPaint * circle.diameter()) / 2) - circle.diameter()/2;
72           painter.mbk(centerOffset);
73   
74           // Paint the row of squares.
75           int painted = 0;
76           while (painted < squaresToPaint){
77               paintOneCircle(painter, circle, color);
78               painter.mfd(circle.diameter());
79               painted = painted + 1;
80           }
81   
82           // Make the method invariant with respect to painter position.
83           painter.mbk(centerOffset + circle.diameter());
84       }
85   
86       private void paintOneCircle(SPainter painter, SCircle square, Color color){
87           painter.setColor(color);
88           square.s2();
89           painter.paint(square);
90           painter.setColor(Color.BLACK);
91           square.x2();
92       }
93   
94       private static int squaresOnLineCount(double lineLength, double sideLength){
95           int squares = ( (int)Math.ceil( ( lineLength - sideLength ) / sideLength ) + 1);
96           return squares;
97       }
98   
99       private double chordLength(double yOffset, SCircle circle){
100          double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2));
101          double chordLength = xLength * 2;
102          return chordLength;
103      }
104  
105      private static int getNumber(String prompt) {
106          String nss = JOptionPane.showInputDialog(null,prompt+"?");
107          Scanner scanner = new Scanner(nss);
108          return scanner.nextInt();
109      }
110  
111      private static Color randomColor() {
112          Random rgen = new Random();
113          int r = rgen.nextInt(256);
114          int g = rgen.nextInt(256);
115          int b = rgen.nextInt(256);
116          return new Color(r,g,b);
117      }
118  
119      public SimpleDots() {
120          paintTheImage();
121      }
122  
123      public static void main(String[] args) {
124          SwingUtilities.invokeLater(new Runnable() {
125              public void run() {
126                  new SimpleDots();
127              }
128          });
129      }
130  }
131