/* * A program to paint, centered on the canvas, a circle of randomly colored, black-framed squares. */ package npw; import painter.SPainter; import shapes.SCircle; import shapes.SSquare; import javax.swing.*; import java.awt.*; import java.util.Random; import java.util.Scanner; public class HirstSquares { private void paintTheImage(){ // Get the input information int radius = getNumber("circle radius"); int side = getNumber("square side length"); // Establish the painter SPainter painter = new SPainter("Circle of Squares", radius*2+50, radius*2+50); painter.setBrushWidth(3); SCircle circle = new SCircle(radius); SSquare square = new SSquare(side); // Paint the squares HirstSquares(painter, circle, square); } private void HirstSquares(SPainter painter, SCircle circle, SSquare square){ // Position the painter to begin drawing the rows painter.mfd(circle.radius()); painter.tr(); // Paint the circle of squares double moved = 0; while (moved < circle.diameter()) { double chord = chordLength(circle.radius() - moved, circle); int squares = squaresOnLineCount(chord, square.side()); paintRow(painter, square, squares); nextRow(painter, square.side()); moved = moved + square.side(); } // Make the method invariant with respect to painter position painter.tl(); painter.mfd(circle.radius()); } // Move to the next row private void nextRow(SPainter painter, double rowHeight){ painter.tr(); painter.mfd(rowHeight); painter.tl(); } // Assumes the painter is at the center of the row to paint, facing right. private void paintRow(SPainter painter, SSquare square, int squaresToPaint){ // Move backward 1/2 of the length we're painting to get ready to paint the row. double centerOffset = ( (squaresToPaint * square.side()) / 2) - square.side()/2; painter.mbk(centerOffset); // Paint the row of squares. int painted = 0; while (painted < squaresToPaint){ paintOneSquare(painter, square); painter.mfd(square.side()); painted = painted + 1; } // Make the method invariant with respect to painter position. painter.mbk(centerOffset + square.side()); } private void paintOneSquare(SPainter painter, SSquare square){ square.s2(); painter.setColor(randomColor()); painter.paint(square); painter.setColor(Color.BLACK); painter.draw(square); square.x2(); } private static int squaresOnLineCount(double lineLength, double sideLength){ int squares = ( (int)Math.ceil( ( lineLength - sideLength ) / sideLength ) + 1); return squares; } private double chordLength(double yOffset, SCircle circle){ double xLength = Math.sqrt(Math.pow(circle.radius(), 2) - Math.pow(yOffset, 2)); double chordLength = xLength * 2; return chordLength; } private static int getNumber(String prompt) { String nss = JOptionPane.showInputDialog(null,prompt+"?"); Scanner scanner = new Scanner(nss); return scanner.nextInt(); } private static Color randomColor() { Random rgen = new Random(); int r = rgen.nextInt(256); int g = rgen.nextInt(256); int b = rgen.nextInt(256); return new Color(r,g,b); } public HirstSquares() { paintTheImage(); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { new HirstSquares(); } }); } }