/* * A program to paint 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 HirstDots { private void paintTheImage(){ int radius = getNumber("circle radius"); int diameter = getNumber("dot diameter length"); SPainter painter = new SPainter("Circle of Dots", radius*2+50, radius*2+50); painter.setBrushWidth(3); SCircle circle = new SCircle(radius); SCircle dot = new SCircle(diameter/2.0); paintCircleOfDots(painter, circle, dot); } private void paintCircleOfDots(SPainter painter, SCircle circle, SCircle dot){ painter.mfd(circle.radius()); painter.tr(); double moved = 0; while (moved < circle.diameter()) { double chord = chordLength(circle.radius() - moved, circle); int dots = dotsOnLineCount(chord, dot.diameter()); paintRow(painter, dot, dots); nextRow(painter, dot.diameter()); moved = moved + dot.diameter(); } painter.tl(); painter.mfd(circle.radius()); } private void nextRow(SPainter painter, double rowHeight){ painter.tr(); painter.mfd(rowHeight); painter.tl(); } private void paintRow(SPainter painter, SCircle dot, int dotsToPaint){ double centerOffset = ( (dotsToPaint * dot.diameter()) / 2) - dot.diameter()/2; painter.mbk(centerOffset); int painted = 0; while (painted < dotsToPaint){ paintOneDot(painter, dot); painter.mfd(dot.diameter()); painted = painted + 1; } painter.mbk(centerOffset + dot.diameter()); } private void paintOneDot(SPainter painter, SCircle dot){ dot.s2(); painter.setColor(randomColor()); painter.paint(dot); dot.x2(); } private static int dotsOnLineCount(double lineLength, double diameter){ int dots = ( (int)Math.ceil( ( lineLength - diameter ) / diameter ) + 1); return dots; } 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 HirstDots() { paintTheImage(); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { new HirstDots(); } }); } }