1    /* 
2     * A program to paint, centered on the canvas, a circle of randomly colored, black-framed squares. 
3     */
4    package npw;
5    
6    import painter.SPainter;
7    import shapes.SCircle;
8    
9    import javax.swing.*;
10   import java.awt.*;
11   import java.util.Scanner;
12   
13   public class SimpleDots {
14   
15       private void paintTheImage(){
16           // Get the input information
17           int radius = getNumber("circle radius");
18           int altRadius = getNumber("small circle radius");
19   
20           // Establish the painter
21           SPainter painter = new SPainter("Simple Dots", radius*2+50, radius*2+50);
22           painter.setBrushWidth(3);
23           SCircle circle = new SCircle(radius);
24           SCircle altCircle = new SCircle(altRadius);
25           Color Color = getColor();
26   
27           // Paint the circles
28           paintHirstCircles(painter, circle, altCircle,Color);
29       }
30   
31       private void paintHirstCircles(SPainter painter, SCircle circle, SCircle altCircle,Color Color){
32           // Position the painter to begin drawing the rows
33           painter.mfd(circle.radius());
34           painter.tr();
35           // Paint the circle of squares
36           double moved = 0;
37           while (moved < circle.diameter()) {
38               double chord = chordLength(circle.radius() - moved, circle);
39               int circles = circlesOnLineCount(chord, altCircle.radius());
40               paintRow(painter, altCircle, circles,Color);
41               nextRow(painter, altCircle.radius());
42               moved = moved + altCircle.radius();
43           }
44           // Make the method invariant with respect to painter position
45           painter.tl();
46           painter.mfd(circle.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 altCircle, int circlesToPaint,Color Color){
58           // Move backward 1/2 of the length we're painting to get ready to paint the row.
59           double centerOffset = ( (circlesToPaint * altCircle.radius()) / 2) - altCircle.radius()/2;
60           painter.mbk(centerOffset);
61   
62           // Paint the row of squares.
63           int painted = 0;
64           while (painted < circlesToPaint){
65               painter.setColor(Color);
66               altCircle.s3();
67               painter.paint(altCircle);
68               altCircle.x3();
69               painter.mfd(altCircle.radius());
70               painted = painted + 1;
71           }
72   
73           // Make the method invariant with respect to painter position.
74           painter.mbk(centerOffset + altCircle.radius());
75       }
76   
77       private void paintOneCircle(SPainter painter, SCircle altCircle) {
78           painter.setColor(getColor());
79           altCircle.s3();
80           painter.paint(altCircle);
81           altCircle.x3();
82       }
83   
84   
85       private static int circlesOnLineCount(double lineLength, double sideLength){
86           int circles = ( (int)Math.ceil( ( lineLength - sideLength ) / sideLength ) + 1);
87           return circles;
88       }
89   
90       private double chordLength(double yOffset, SCircle circle){
91           double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2));
92           double chordLength = xLength * 2;
93           return chordLength;
94       }
95   
96       private static int getNumber(String prompt) {
97           String nss = JOptionPane.showInputDialog(null,prompt+"?");
98           Scanner scanner = new Scanner(nss);
99           return scanner.nextInt();
100      }
101  
102      private static Color getColor() {
103          String color = JOptionPane.showInputDialog(null,"color?");
104          if (color.equalsIgnoreCase("blue")) {
105              return Color.BLUE;
106          } else if (color.equalsIgnoreCase("red")) {
107              return Color.RED;
108          } else if (color.equalsIgnoreCase("green")) {
109              return Color.GREEN;
110          } else {
111              return Color.BLACK;
112          }
113      }
114  
115  
116      public SimpleDots() {
117          paintTheImage();
118      }
119  
120      public static void main(String[] args) {
121          SwingUtilities.invokeLater(new Runnable() {
122              public void run() {
123                  new SimpleDots();
124              }
125          });
126      }
127  }
128