1    /* 
2     * A program to paint, centered on the canvas, a circle of a red, blue, green, or black set of circles that are spaced out based on users input 
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.Scanner;
13   
14   public class SimpleDots {
15   
16       private void paintTheImage() {
17           // Get the input information
18           int radius = getNumber("circle radius");
19           int dotradius = getNumber("dotcircle radius");
20           String dotColor = getColor("color of dot");
21   
22   
23           // Establish the painter
24           SPainter painter = new SPainter("SimpleDots", radius * 2 + 50, radius * 2 + 50);
25           painter.setBrushWidth(3);
26           SCircle circle = new SCircle(radius);
27           SCircle dot = new SCircle(dotradius);
28   
29           // Paint the squares
30           paintSimpleDots(painter, circle, dot, dotColor);
31       }
32   
33       private void paintSimpleDots(SPainter painter, SCircle circle, SCircle dot, String dotColor) {
34           // Position the painter to begin drawing the rows
35           painter.mfd(circle.radius());
36           painter.tr();
37           // Paint the circle of squares
38           double moved = 0;
39           while (moved < circle.diameter()) {
40               double chord = chordLength(circle.radius() - moved, circle);
41               int squares = squaresOnLineCount(chord, dot.radius());
42               paintRow(painter, dot, squares, dotColor);
43               nextRow(painter, dot.radius());
44               moved = moved + dot.radius();
45           }
46           // Make the method invariant with respect to painter position
47           painter.tl();
48           painter.mfd(circle.radius());
49       }
50   
51       // Move to the next row
52       private void nextRow(SPainter painter, double rowHeight) {
53           painter.tr();
54           painter.mfd(rowHeight);
55           painter.tl();
56       }
57   
58       // Assumes the painter is at the center of the row to paint, facing right.
59       private void paintRow(SPainter painter, SCircle dot, int squaresToPaint, String dotColor) {
60           // Move backward 1/2 of the length we're painting to get ready to paint the row.
61           double centerOffset = ((squaresToPaint * dot.radius()) / 2) - dot.radius() / 2;
62           painter.mbk(centerOffset);
63   
64           // Paint the row of squares.
65           int painted = 0;
66           while (painted < squaresToPaint) {
67               paintOneDot(painter, dot, dotColor);
68               painter.mfd(dot.radius());
69               painted = painted + 1;
70           }
71   
72           // Make the method invariant with respect to painter position.
73           painter.mbk(centerOffset + dot.radius());
74       }
75   
76       private void paintOneDot(SPainter painter, SCircle dot, String dotColor) {
77           // Color dots based on input
78           if (dotColor.equalsIgnoreCase("blue")) {
79               painter.setColor(Color.blue);
80           } else if (dotColor.equalsIgnoreCase("red")){
81               painter.setColor(Color.red);
82           } else if (dotColor.equalsIgnoreCase("green")) {
83               painter.setColor(Color.green);
84           } else {
85               painter.setColor(Color.black);
86           }
87   
88           dot.s2();
89           dot.s2();
90           painter.paint(dot);
91           dot.x2();
92           dot.x2();
93   
94       }
95   
96       private static int squaresOnLineCount(double lineLength, double sideLength) {
97           int squares = ((int) Math.ceil((lineLength - sideLength) / sideLength) + 1);
98           return squares;
99       }
100  
101      private double chordLength(double yOffset, SCircle circle) {
102          double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2));
103          double chordLength = xLength * 2;
104          return chordLength;
105      }
106  
107      private static int getNumber(String prompt) {
108          String nss = JOptionPane.showInputDialog(null, prompt + "?");
109          Scanner scanner = new Scanner(nss);
110          return scanner.nextInt();
111      }
112  
113      private static String getColor(String prompt) {
114          String nss = JOptionPane.showInputDialog(null, prompt + "?");
115          Scanner scanner = new Scanner(nss);
116          return scanner.next();
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  }