1    /* 
2    A program to paint, centered on a canvas, a circle of colored circles spaced from each other. 
3     */
4    
5    package npw;
6    
7    import painter.SPainter;
8    import shapes.SCircle;
9    import shapes.SSquare;
10   
11   import javax.swing.*;
12   import java.awt.*;
13   import java.util.Random;
14   import java.util.Scanner;
15   
16   public class SimpleDots{
17   
18       private void paintTheImage(){
19           //Get input information
20           int radius = getNumber("large circle radius");
21           int side = getNumber("small circles radius");
22           String color = getString("green, blue, or red");
23   
24           //Establish the painter
25           SPainter painter = new SPainter("Simple Dots",((radius*2)+50),((radius*2)+50));
26           painter.setBrushWidth(3);
27           SCircle circle = new SCircle(radius);
28           SCircle hirst = new SCircle(side);
29   
30           //Paint the squares
31           paintCircleOfSquares(color, painter,circle,hirst);
32       }
33   
34       private void paintCircleOfSquares(String color, SPainter painter, SCircle circle, SCircle hirst){
35           //Position the painter to begin drawing the rows
36           painter.mfd(circle.radius());
37           painter.tr();
38           //Paint the circle of squares
39           double moved=0;
40           while (moved < circle.diameter()) {
41               double chord = chordLength(circle.radius()-moved, circle);
42               int squares = squaresOnLineCount(chord, hirst.diameter());
43               paintRow(color, painter, hirst, squares);
44               nextRow(painter, hirst.diameter());
45               moved=moved+hirst.diameter();
46           }
47           //Make the method invariant with respect to painter position
48           painter.tl();
49           painter.mfd(circle.radius());
50       }
51   
52       //Move to the next row
53       private void nextRow(SPainter painter, double rowHeight){
54           painter.tr();
55           painter.mfd(rowHeight);
56           painter.tl();
57       }
58   
59       //Assumes the painter is at the center of the row to paint, facing right
60       private void paintRow(String color, SPainter painter, SCircle hirst, int squaresToPaint){
61           //Move backward 1/2 of the length we're painting to get ready to paint the row
62           double centerOffset = (((squaresToPaint*hirst.diameter())/2)-hirst.diameter()/2);
63           painter.mbk(centerOffset);
64   
65           //Paint the row of squares
66           int painted=0;
67           while (painted < squaresToPaint) {
68               paintOneSquare(color,painter,hirst);
69               painter.mfd(hirst.diameter());
70               painted=painted+1;
71           }
72   
73           //make the method invariant with respect to painter position
74           painter.mbk(centerOffset+hirst.diameter());
75       }
76   
77       private void paintOneSquare(String color, SPainter painter, SCircle hirst){
78           hirst.s2();
79           painter.setColor(color(color));
80           painter.paint(hirst);
81           hirst.x2();
82       }
83   
84       private static int squaresOnLineCount(double lineLength, double sideLength){
85           int hirsts = ((int)Math.ceil((lineLength-sideLength)/sideLength)+1);
86           return hirsts;
87       }
88   
89       private double chordLength(double yOffset, SCircle circle){
90           double xLength=Math.sqrt(Math.pow(circle.radius(),2)-Math.pow(yOffset,2));
91           double chordLength=xLength*2;
92           return chordLength;
93       }
94   
95       private static int getNumber(String prompt) {
96           String nss = JOptionPane.showInputDialog(null,prompt+"?");
97           Scanner scanner = new Scanner(nss);
98           return scanner.nextInt();
99       }
100  
101      private static String getString(String prompt) {
102          String nss = JOptionPane.showInputDialog(null,prompt+"?");
103          Scanner scanner = new Scanner(nss);
104          return scanner.next();
105      }
106  
107      private static Color color(String color) {
108          if (color.equalsIgnoreCase("green")) {
109              return Color.GREEN;
110          } else if (color.equalsIgnoreCase("blue")) {
111              return Color.BLUE;
112          } else if (color.equalsIgnoreCase("red")) {
113              return Color.RED;
114          } else {
115              return Color.BLACK;
116          }
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  }