1    /* 
2     * Assignment 4 Problem 2: Circle Of Squares 
3     * A program to paint, centered on the canvas, a circle of randomly colored,black-framed squares 
4     */
5    
6    package npw;
7    
8    import painter.SPainter;
9    import shapes.SCircle;
10   import shapes.SSquare;
11   import javax.swing.*;
12   import java.awt.*;
13   import java.util.Random;
14   import java.util.Scanner;
15   
16   
17   public class CircleOfSquares {
18       public static void main(String[] args){
19           SwingUtilities.invokeLater(new Runnable() {
20               public void run() {
21                   new CircleOfSquares();
22               }
23           });
24       }
25       public CircleOfSquares() {
26           paintTheImage();
27       }
28   
29       private void paintTheImage() {
30           // Get the input information
31           // create new method named "getNumber" to scan from input
32           int radius = getNumber("circle radius");
33           int side = getNumber("square side length");
34   
35           // Establish the painter
36           // Create new painter with Canvas names "Circle of Squares" and side of Circle diameter plus 50
37           SPainter painter = new SPainter("Circle of Squares", radius*2+50, radius*2+50);
38           // Painter's brushWidth widen so that the side of the square could be more visible
39           painter.setBrushWidth(3);
40           SCircle circle = new SCircle(radius);
41           SSquare square = new SSquare(side);
42   
43           // Paint the squares
44           // Created new method named "paintCircleOfSquares" with parameter of painter,circle,and square
45           paintCircleOfSquares(painter, circle, square);
46       }
47   
48       private void paintCircleOfSquares(SPainter painter, SCircle circle, SSquare square) {
49           // Position the painter to begin drawing the rows
50           painter.mfd(circle.radius()); // painter move forward as circle radius
51           painter.tr(); 
52           // Paint the circle of squares
53           double moved = 0;
54           while (moved < circle.diameter()){
55               double chord = chordLength(circle.radius()-moved,circle);
56               // number of square on the chord line so that the painter can know how many square to paint on a line
57               int squares = squaresOnLineCount(chord,square.side());
58               paintRow(painter, square, squares);
59               nextRow(painter, square.side());
60               moved = moved+square.side();
61           }
62           // Make the method invariant with respect to painter position
63           painter.tl();
64           painter.mfd(circle.radius()); 
65       }
66   
67       // Move to next row
68       private void nextRow(SPainter painter, double rowHeight) {
69           painter.tr();
70           painter.mfd(rowHeight);
71           painter.tl();
72       }
73   
74       // Assumes the painter is at the center of the row to paint, facing right.
75       private void paintRow(SPainter painter, SSquare square, int squaresToPaint) {
76           double centerOffset= ((squaresToPaint*square.side())/2)- square.side()/2;
77           painter.mbk(centerOffset);
78   
79           // Paint the row of squares
80           int painted = 0;
81           while (painted < squaresToPaint){
82               paintOneSquare(painter,square);
83               painter.mfd(square.side());
84               painted = painted + 1;
85           }
86   
87           // Make the method invariant with respect to painter position.
88           painter.mbk(centerOffset + square.side());
89       }
90   
91       private void paintOneSquare(SPainter painter, SSquare square) {
92           painter.setColor(randomColor());
93           painter.paint(square);
94           painter.setColor(Color.BLACK);
95           painter.draw(square);
96       }
97   
98       private static Color randomColor() {
99           Random rgen = new Random();
100          int r = rgen.nextInt(256);
101          int g = rgen.nextInt(256);
102          int b = rgen.nextInt(256);
103          return new Color (r,g,b);
104      }
105  
106      // LineLength is the Chord Length, side Length is length of the square
107      private static int squaresOnLineCount(double lineLength, double sideLength) {
108          //Math.ceil return the smallest integer that is greater or equal to the input.
109          int squares = ((int)Math.ceil((lineLength-sideLength)/sideLength)+1);
110          return squares;
111      }
112  
113      private double chordLength(double yOffset, SCircle circle) {
114          double xLength = Math.sqrt(Math.pow(circle.radius(),2)-Math.pow(yOffset,2));
115          double chordLength = xLength * 2;
116          // chord length = 2 * Square root of (r2 * d*)
117          return chordLength;
118      }
119  
120      private static int getNumber(String prompt) {
121          // The input from the Input Dialog is a string so need to scanner to make sure it's a int.
122          String nss = JOptionPane.showInputDialog(null,prompt+"?");
123          Scanner scanner = new Scanner(nss);
124          return scanner.nextInt();
125      }
126  }
127