package npw; import painter.SPainter; import shapes.SCircle; import javax.swing.*; import java.awt.*; import java.util.Scanner; public class HirstDots { public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { new HirstDots(); } }); } public HirstDots() { paintTheImage(); } private void paintTheImage(){ // Grab the input information int width = getNumber("width"); int height = getNumber("height"); int dotSpacing = getNumber("dot spacing"); // Establish the painter SPainter painter = new SPainter("Hirst Dots", width, height); SCircle dot = new SCircle(5); // Move the painter to the upper left corner to get ready to paint the gradient painter.mfd(height/2); painter.tl(90); painter.mfd(width/2 - 10); painter.tl(90); // Paint it! paintGradient(painter, dot, height, width, dotSpacing); } private static int getNumber(String prompt) { String nss = JOptionPane.showInputDialog(null,prompt+"?"); Scanner scanner = new Scanner(nss); return scanner.nextInt(); } private void paintGradient(SPainter painter, SCircle dot, int height, int width, int dotSpacing){ int cols = 0; // Calcuate the number of columns. We want to fill the screen, but we don't want // any dots only half on the canvas, so we subtract some space. int nrOfCols = ( width / dotSpacing ) - 2; while (cols < nrOfCols){ nextCol(painter, dotSpacing); paintColumn(painter, dot, height, dotSpacing); cols = cols + 1; } } private void paintOneDot(SPainter painter, SCircle dot){ painter.setColor(randomColor()); painter.paint(dot); } private static Color randomColor(){ int rv = (int)(Math.random()*256); int gv = (int)(Math.random()*256); int bv = (int)(Math.random()*256); return new Color(rv, gv, bv); } // Dots are spaced tighter together near the bottom of the canvas. private void paintColumn(SPainter painter, SCircle dot, int height, int dotSpacing) { int travel = 0; int totalDistanceTraveled = 0; // Paint a row with decreasing distance between dots. while(totalDistanceTraveled < height - (dot.radius() * 3)) { travel = dotSpacing; totalDistanceTraveled = totalDistanceTraveled + travel; painter.mfd(travel); paintOneDot(painter, dot); } // Make the method invariant with respect to painter position. painter.mbk(totalDistanceTraveled); } // Moves the painter to the next column. private void nextCol(SPainter painter, int dotSpacing){ painter.tl(90); painter.mfd(dotSpacing); painter.tr(90); } }