/****************************************************************************** * Compilation: javac Draw.java * Execution: java Draw * Dependencies: none * * Drawing library. This class provides a basic capability for creating * drawings with your programs. It uses a simple graphics model that * allows you to create drawings consisting of points, lines, and curves * in a window on your computer and to save the drawings to a file. * This is the object-oriented version of standard draw; it supports * multiple independent drawing windows. * * Todo * ---- * - Add support for gradient fill, etc. * * Remarks * ------- * - don't use AffineTransform for rescaling since it inverts * images and strings * - careful using setFont in inner loop within an animation - * it can cause flicker * ******************************************************************************/ import java.awt.BasicStroke; import java.awt.Color; import java.awt.Component; import java.awt.FileDialog; import java.awt.Font; import java.awt.FontMetrics; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Image; import java.awt.MediaTracker; import java.awt.RenderingHints; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.MouseMotionListener; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import java.util.Timer; import java.util.TimerTask; import java.awt.geom.Arc2D; import java.awt.geom.Ellipse2D; import java.awt.geom.GeneralPath; import java.awt.geom.Line2D; import java.awt.geom.Rectangle2D; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import java.net.MalformedURLException; import java.net.URL; import java.net.URI; import java.net.URISyntaxException; import java.util.ArrayList; import java.util.LinkedList; import java.util.TreeSet; import javax.imageio.ImageIO; import javax.swing.ImageIcon; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.KeyStroke; /** * The Draw data type provides a basic capability for * creating drawings with your programs. It uses a simple graphics model that * allows you to create drawings consisting of points, lines, and curves * in a window on your computer and to save the drawings to a file. * This is the object-oriented version of standard draw; it supports * multiple independent drawing windows. *

* For additional documentation, see * Section 3.1 of * Computer Science: An Interdisciplinary Approach by Robert Sedgewick and Kevin Wayne. * * @author Robert Sedgewick * @author Kevin Wayne */ public final class Draw implements ActionListener, MouseListener, MouseMotionListener, KeyListener { /** * The color aqua (0, 255, 255). */ public static final Color AQUA = new Color(0, 255, 255); /** * The color black (0, 0, 0). */ public static final Color BLACK = Color.BLACK; /** * The color blue (0, 0, 255). */ public static final Color BLUE = Color.BLUE; /** * The color cyan (0, 255, 255). */ public static final Color CYAN = Color.CYAN; /** * The color fuscia (255, 0, 255). */ public static final Color FUSCIA = new Color(255, 0, 255); /** * The color dark gray (64, 64, 64). */ public static final Color DARK_GRAY = Color.DARK_GRAY; /** * The color gray (128, 128, 128). */ public static final Color GRAY = Color.GRAY; /** * The color green (0, 128, 0). */ public static final Color GREEN = new Color(0, 128, 0); /** * The color light gray (192, 192, 192). */ public static final Color LIGHT_GRAY = Color.LIGHT_GRAY; /** * The color lime (0, 255, 0). */ public static final Color LIME = new Color(0, 255, 0); /** * The color magenta (255, 0, 255). */ public static final Color MAGENTA = Color.MAGENTA; /** * The color maroon (128, 0, 0). */ public static final Color MAROON = new Color(128, 0, 0); /** * The color navy (0, 0, 128). */ public static final Color NAVY = new Color(0, 0, 128); /** * The color olive (128, 128, 0). */ public static final Color OLIVE = new Color(128, 128, 0); /** * The color orange (255, 200, 0). */ public static final Color ORANGE = Color.ORANGE; /** * The color pink (255, 175, 175). */ public static final Color PINK = Color.PINK; /** * The color purple (128, 0, 128). */ public static final Color PURPLE = new Color(128, 0, 128); /** * The color red (255, 0, 0). */ public static final Color RED = Color.RED; /** * The color silver (192, 192, 192). */ public static final Color SILVER = new Color(192, 192, 192); /** * The color teal (0, 128, 128). */ public static final Color TEAL = new Color(0, 128, 128); /** * The color white (255, 255, 255). */ public static final Color WHITE = Color.WHITE; /** * The color yellow (255, 255, 0). */ public static final Color YELLOW = Color.YELLOW; /** * A 100% transparent color, for a transparent background. */ public static final Color TRANSPARENT = new Color(0, 0, 0, 0); /** * The shade of blue used in Introduction to Programming in Java. * It is Pantone 300U. The RGB values are approximately (9, 90, 166). */ public static final Color BOOK_BLUE = new Color(9, 90, 166); /** * The shade of light blue used in Introduction to Programming in Java. * The RGB values are approximately (103, 198, 243). */ public static final Color BOOK_LIGHT_BLUE = new Color(103, 198, 243); /** * The shade of red used in Algorithms, 4th edition. * It is Pantone 1805U. The RGB values are approximately (150, 35, 31). */ public static final Color BOOK_RED = new Color(150, 35, 31); /** * The shade of orange used in Princeton University's identity. * It is PMS 158. The RGB values are approximately (245, 128, 37). */ public static final Color PRINCETON_ORANGE = new Color(245, 128, 37); // default colors private static final Color DEFAULT_PEN_COLOR = BLACK; private static final Color DEFAULT_BACKGROUND_COLOR = WHITE; // boundary of drawing canvas, 0% border private static final double BORDER = 0.0; private static final double DEFAULT_XMIN = 0.0; private static final double DEFAULT_XMAX = 1.0; private static final double DEFAULT_YMIN = 0.0; private static final double DEFAULT_YMAX = 1.0; // default canvas size is SIZE-by-SIZE private static final int DEFAULT_SIZE = 512; // default pen radius private static final double DEFAULT_PEN_RADIUS = 0.002; // default font private static final Font DEFAULT_FONT = new Font("SansSerif", Font.PLAIN, 16); // default title of drawing window private static final String DEFAULT_WINDOW_TITLE = "Draw"; // current pen color private Color penColor = DEFAULT_PEN_COLOR; // background color private Color backgroundColor = DEFAULT_BACKGROUND_COLOR; // current title of drawing window private String windowTitle = DEFAULT_WINDOW_TITLE; // canvas size private int width = DEFAULT_SIZE; private int height = DEFAULT_SIZE; // current pen radius private double penRadius = DEFAULT_PEN_RADIUS; // show we draw immediately or wait until next show? private boolean defer = false; private double xmin = DEFAULT_XMIN; private double xmax = DEFAULT_XMAX; private double ymin = DEFAULT_YMIN; private double ymax = DEFAULT_YMAX; // for synchronization private final Object mouseLock = new Object(); private final Object keyLock = new Object(); // current font private Font font = DEFAULT_FONT; // the JLabel for drawing private JLabel draw; // double buffered graphics private BufferedImage offscreenImage, onscreenImage; private Graphics2D offscreen, onscreen; // the frame for drawing to the screen private JFrame frame; // is the JFrame visible (upon calling draw())? private static boolean isJFrameVisible = true; // mouse state private boolean isMousePressed = false; private double mouseX = 0; private double mouseY = 0; // keyboard state private final LinkedList keysTyped = new LinkedList(); private final TreeSet keysDown = new TreeSet(); // event-based listeners private final ArrayList listeners = new ArrayList(); // timer private Timer timer; /** * Initializes an empty drawing object. */ public Draw() { initCanvas(); initGUI(); } // initialize the drawing canvas private void initCanvas() { // BufferedImage stuff offscreenImage = new BufferedImage(2*width, 2*height, BufferedImage.TYPE_INT_ARGB); onscreenImage = new BufferedImage(2*width, 2*height, BufferedImage.TYPE_INT_ARGB); offscreen = offscreenImage.createGraphics(); onscreen = onscreenImage.createGraphics(); offscreen.scale(2.0, 2.0); // since we made it 2x as big // initialize drawing window offscreen.setBackground(DEFAULT_BACKGROUND_COLOR); offscreen.clearRect(0, 0, width, height); onscreen.setBackground(DEFAULT_BACKGROUND_COLOR); onscreen.clearRect(0, 0, 2*width, 2*height); // set the pen color offscreen.setColor(penColor); // add antialiasing RenderingHints hints = new RenderingHints(null); hints.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); hints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); offscreen.addRenderingHints(hints); } // initialize the GUI private void initGUI() { // create the JFrame (if necessary) if (frame == null) { frame = new JFrame(); frame.addKeyListener(this); // JLabel cannot get keyboard focus frame.setFocusTraversalKeysEnabled(false); // allow VK_TAB with isKeyPressed() frame.setResizable(false); // frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // closes all windows frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); // closes only current window frame.setTitle(windowTitle); frame.setJMenuBar(createMenuBar()); } // create the ImageIcon RetinaImageIcon icon = new RetinaImageIcon(onscreenImage); draw = new JLabel(icon); draw.addMouseListener(this); draw.addMouseMotionListener(this); // finish up the JFrame frame.setContentPane(draw); frame.pack(); frame.requestFocusInWindow(); frame.setVisible(false); } /** * Makes the drawing window visible or invisible. * * @param isVisible if {@code true}, makes the drawing window visible, * otherwise hides the drawing window. */ public void setVisible(boolean isVisible) { isJFrameVisible = isVisible; frame.setVisible(isVisible); } /** * Sets the upper-left hand corner of the drawing window to be (x, y), * where (0, 0) is upper left. * * @param x the number of pixels from the left * @param y the number of pixels from the top * @throws IllegalArgumentException if the width or height is 0 or negative */ public void setLocationOnScreen(int x, int y) { if (x <= 0 || y <= 0) throw new IllegalArgumentException(); frame.setLocation(x, y); } /** * Sets the default close operation. * * @param value the value, typically {@code JFrame.EXIT_ON_CLOSE} * (close all windows) or {@code JFrame.DISPOSE_ON_CLOSE} * (close current window) */ public void setDefaultCloseOperation(int value) { frame.setDefaultCloseOperation(value); } /** * Sets the canvas (drawing area) to be 512-by-512 pixels. * This also clears the current drawing using the default background color (white). * Ordinarily, this method is called once, at the very beginning of a program. */ public void setCanvasSize() { setCanvasSize(DEFAULT_SIZE, DEFAULT_SIZE); } /** * Sets the canvas (drawing area) to be width-by-height pixels. * This also clears the current drawing using the default background color (white). * Ordinarily, this method is called once, at the very beginning of a program. * * @param canvasWidth the width as a number of pixels * @param canvasHeight the height as a number of pixels * @throws IllegalArgumentException unless both {@code canvasWidth} * and {@code canvasHeight} are positive */ public void setCanvasSize(int canvasWidth, int canvasHeight) { if (canvasWidth < 1 || canvasHeight < 1) { throw new IllegalArgumentException("width and height must be positive"); } width = canvasWidth; height = canvasHeight; initCanvas(); initGUI(); } // create the menu bar private JMenuBar createMenuBar() { JMenuBar menuBar = new JMenuBar(); JMenu menu = new JMenu("File"); menuBar.add(menu); JMenuItem menuItem1 = new JMenuItem(" Save... "); menuItem1.addActionListener(this); // Java 11: use getMenuShortcutKeyMaskEx() // Java 8: use getMenuShortcutKeyMask() menuItem1.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_S, Toolkit.getDefaultToolkit().getMenuShortcutKeyMaskEx())); menu.add(menuItem1); return menuBar; } /** * Closes the drawing window. * This allows the client program to terminate instead of requiring * the user to close the drawing window manually. * Drawing after calling this method will restore the previous window state. */ public void close() { frame.dispose(); } /*************************************************************************** * Input validation helper methods. ***************************************************************************/ // throw an IllegalArgumentException if x is NaN or infinite private static void validate(double x, String name) { if (Double.isNaN(x)) throw new IllegalArgumentException(name + " is NaN"); if (Double.isInfinite(x)) throw new IllegalArgumentException(name + " is infinite"); } // throw an IllegalArgumentException if s is null private static void validateNonnegative(double x, String name) { if (x < 0) throw new IllegalArgumentException(name + " negative"); } // throw an IllegalArgumentException if s is null private static void validateNotNull(Object x, String name) { if (x == null) throw new IllegalArgumentException(name + " is null"); } /*************************************************************************** * Set the title of the drawing window. ***************************************************************************/ /** * Sets the title of the drawing window to the specified string. * * @param windowTitle the title of the window * @throws IllegalArgumentException if {@code title} is {@code null} */ public void setTitle(String windowTitle) { validateNotNull(windowTitle, "title"); this.windowTitle = windowTitle; frame.setTitle(windowTitle); } /*************************************************************************** * User and screen coordinate systems. ***************************************************************************/ /** * Sets the x-scale to the default range (between 0.0 and 1.0). */ public void setXscale() { setXscale(DEFAULT_XMIN, DEFAULT_XMAX); } /** * Sets the y-scale to the default range (between 0.0 and 1.0). */ public void setYscale() { setYscale(DEFAULT_YMIN, DEFAULT_YMAX); } /** * Sets the x-scale to the specified range. * * @param min the minimum value of the x-scale * @param max the maximum value of the x-scale * @throws IllegalArgumentException if {@code (max == min)} * @throws IllegalArgumentException if either {@code min} or {@code max} is either NaN or infinite */ public void setXscale(double min, double max) { validate(min, "min"); validate(max, "max"); double size = max - min; if (size == 0.0) throw new IllegalArgumentException("the min and max are the same"); xmin = min - BORDER * size; xmax = max + BORDER * size; } /** * Sets the y-scale to the specified range. * * @param min the minimum value of the y-scale * @param max the maximum value of the y-scale * @throws IllegalArgumentException if {@code (max == min)} * @throws IllegalArgumentException if either {@code min} or {@code max} is either NaN or infinite */ public void setYscale(double min, double max) { validate(min, "min"); validate(max, "max"); double size = max - min; if (size == 0.0) throw new IllegalArgumentException("the min and max are the same"); ymin = min - BORDER * size; ymax = max + BORDER * size; } /** * Sets both the x-scale and y-scale to the default range (between 0.0 and 1.0). */ public void setScale() { setXscale(); setYscale(); } /** * Sets both the x-scale and y-scale to the (same) specified range. * @param min the minimum value of the y-scale * @param max the maximum value of the y-scale * @throws IllegalArgumentException if {@code (max == min)} * @throws IllegalArgumentException if either {@code min} or {@code max} is either NaN or infinite */ public void setScale(double min, double max) { setXscale(min, max); setYscale(min, max); } // helper functions that scale from user coordinates to screen coordinates and back private double scaleX(double x) { return width * (x - xmin) / (xmax - xmin); } private double scaleY(double y) { return height * (ymax - y) / (ymax - ymin); } private double factorX(double w) { return w * width / Math.abs(xmax - xmin); } private double factorY(double h) { return h * height / Math.abs(ymax - ymin); } private double userX(double x) { return xmin + x * (xmax - xmin) / width; } private double userY(double y) { return ymax - y * (ymax - ymin) / height; } /** * Clears the screen using the default background color (white). */ public void clear() { clear(DEFAULT_BACKGROUND_COLOR); } /** * Clears the screen using the specified background color. * To make the background transparent, use {@code Draw.TRANSPARENT}. * * @param color the color to make the background * @throws IllegalArgumentException if {@code color} is {@code null} */ public void clear(Color color) { validateNotNull(color, "color"); backgroundColor = color; offscreen.setBackground(backgroundColor); offscreen.clearRect(0, 0, width, height); draw(); } /** * Returns the current pen radius. * * @return the current pen radius */ public double getPenRadius() { return penRadius; } /** * Sets the pen radius to the default (0.002). */ public void setPenRadius() { setPenRadius(DEFAULT_PEN_RADIUS); } /** * Sets the radius of the pen to the given size. * * @param radius the radius of the pen * @throws IllegalArgumentException if {@code radius} is negative, NaN, or infinite */ public void setPenRadius(double radius) { validate(radius, "pen radius"); validateNonnegative(radius, "pen radius"); penRadius = radius * DEFAULT_SIZE; BasicStroke stroke = new BasicStroke((float) penRadius, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND); // BasicStroke stroke = new BasicStroke((float) penRadius); offscreen.setStroke(stroke); } /** * Returns the current pen color. * * @return the current pen color */ public Color getPenColor() { return penColor; } /** * Returns the current background color. * * @return the current background color */ public Color getBackgroundColor() { return backgroundColor; } /** * Sets the pen color to the default color (black). */ public void setPenColor() { setPenColor(DEFAULT_PEN_COLOR); } /** * Sets the pen color to the given color. * * @param color the color to make the pen * @throws IllegalArgumentException if {@code color} is {@code null} */ public void setPenColor(Color color) { validateNotNull(color, "color"); penColor = color; offscreen.setColor(penColor); } /** * Sets the pen color to the given RGB color. * * @param red the amount of red (between 0 and 255) * @param green the amount of green (between 0 and 255) * @param blue the amount of blue (between 0 and 255) * @throws IllegalArgumentException if {@code red}, {@code green}, * or {@code blue} is outside its prescribed range */ public void setPenColor(int red, int green, int blue) { if (red < 0 || red >= 256) throw new IllegalArgumentException("red must be between 0 and 255"); if (green < 0 || green >= 256) throw new IllegalArgumentException("green must be between 0 and 255"); if (blue < 0 || blue >= 256) throw new IllegalArgumentException("blue must be between 0 and 255"); setPenColor(new Color(red, green, blue)); } /** * Turns on xor mode. */ public void xorOn() { offscreen.setXORMode(backgroundColor); } /** * Turns off xor mode. */ public void xorOff() { offscreen.setPaintMode(); } /** * Returns the current {@code JLabel} for use in some other GUI. * * @return the current {@code JLabel} */ public JLabel getJLabel() { return draw; } /** * Returns the current font. * * @return the current font */ public Font getFont() { return font; } /** * Sets the font to the default font (sans serif, 16 point). */ public void setFont() { setFont(DEFAULT_FONT); } /** * Sets the font to the given value. * * @param font the font * @throws IllegalArgumentException if {@code font} is {@code null} */ public void setFont(Font font) { validateNotNull(font, "font"); this.font = font; } /*************************************************************************** * Drawing geometric shapes. ***************************************************************************/ /** * Draws a line from (x0, y0) to (x1, y1). * * @param x0 the x-coordinate of the starting point * @param y0 the y-coordinate of the starting point * @param x1 the x-coordinate of the destination point * @param y1 the y-coordinate of the destination point * @throws IllegalArgumentException if any coordinate is either NaN or infinite */ public void line(double x0, double y0, double x1, double y1) { validate(x0, "x0"); validate(y0, "y0"); validate(x1, "x1"); validate(y1, "y1"); offscreen.draw(new Line2D.Double(scaleX(x0), scaleY(y0), scaleX(x1), scaleY(y1))); draw(); } /** * Draws one pixel at (x, y). * * @param x the x-coordinate of the pixel * @param y the y-coordinate of the pixel * @throws IllegalArgumentException if {@code x} or {@code y} is either NaN or infinite */ private void pixel(double x, double y) { validate(x, "x"); validate(y, "y"); offscreen.fillRect((int) Math.round(scaleX(x)), (int) Math.round(scaleY(y)), 1, 1); } /** * Draws a point at (x, y). * * @param x the x-coordinate of the point * @param y the y-coordinate of the point * @throws IllegalArgumentException if either {@code x} or {@code y} is either NaN or infinite */ public void point(double x, double y) { validate(x, "x"); validate(y, "y"); double xs = scaleX(x); double ys = scaleY(y); double r = penRadius; // double ws = factorX(2*r); // double hs = factorY(2*r); // if (ws <= 1 && hs <= 1) pixel(x, y); if (r <= 1) pixel(x, y); else offscreen.fill(new Ellipse2D.Double(xs - r/2, ys - r/2, r, r)); draw(); } /** * Draws a circle of the specified radius, centered at (x, y). * * @param x the x-coordinate of the center of the circle * @param y the y-coordinate of the center of the circle * @param radius the radius of the circle * @throws IllegalArgumentException if {@code radius} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void circle(double x, double y, double radius) { validate(x, "x"); validate(y, "y"); validate(radius, "radius"); validateNonnegative(radius, "radius"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*radius); double hs = factorY(2*radius); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.draw(new Ellipse2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a filled circle of the specified radius, centered at (x, y). * * @param x the x-coordinate of the center of the circle * @param y the y-coordinate of the center of the circle * @param radius the radius of the circle * @throws IllegalArgumentException if {@code radius} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void filledCircle(double x, double y, double radius) { validate(x, "x"); validate(y, "y"); validate(radius, "radius"); validateNonnegative(radius, "radius"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*radius); double hs = factorY(2*radius); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.fill(new Ellipse2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws an ellipse with the specified semimajor and semiminor axes, * centered at (x, y). * * @param x the x-coordinate of the center of the ellipse * @param y the y-coordinate of the center of the ellipse * @param semiMajorAxis is the semimajor axis of the ellipse * @param semiMinorAxis is the semiminor axis of the ellipse * @throws IllegalArgumentException if either {@code semiMajorAxis} * or {@code semiMinorAxis} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void ellipse(double x, double y, double semiMajorAxis, double semiMinorAxis) { validate(x, "x"); validate(y, "y"); validate(semiMajorAxis, "semimajor axis"); validate(semiMinorAxis, "semiminor axis"); validateNonnegative(semiMajorAxis, "semimajor axis"); validateNonnegative(semiMinorAxis, "semiminor axis"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*semiMajorAxis); double hs = factorY(2*semiMinorAxis); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.draw(new Ellipse2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a filled ellipse with the specified semimajor and semiminor axes, * centered at (x, y). * * @param x the x-coordinate of the center of the ellipse * @param y the y-coordinate of the center of the ellipse * @param semiMajorAxis is the semimajor axis of the ellipse * @param semiMinorAxis is the semiminor axis of the ellipse * @throws IllegalArgumentException if either {@code semiMajorAxis} * or {@code semiMinorAxis} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void filledEllipse(double x, double y, double semiMajorAxis, double semiMinorAxis) { validate(x, "x"); validate(y, "y"); validate(semiMajorAxis, "semimajor axis"); validate(semiMinorAxis, "semiminor axis"); validateNonnegative(semiMajorAxis, "semimajor axis"); validateNonnegative(semiMinorAxis, "semiminor axis"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*semiMajorAxis); double hs = factorY(2*semiMinorAxis); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.fill(new Ellipse2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a circular arc of the specified radius, * centered at (x, y), from angle1 to angle2 (in degrees). * * @param x the x-coordinate of the center of the circle * @param y the y-coordinate of the center of the circle * @param radius the radius of the circle * @param angle1 the starting angle. 0 would mean an arc beginning at 3 o'clock. * @param angle2 the angle at the end of the arc. For example, if * you want a 90 degree arc, then angle2 should be angle1 + 90. * @throws IllegalArgumentException if {@code radius} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void arc(double x, double y, double radius, double angle1, double angle2) { validate(x, "x"); validate(y, "y"); validate(radius, "arc radius"); validate(angle1, "angle1"); validate(angle2, "angle2"); validateNonnegative(radius, "arc radius"); while (angle2 < angle1) angle2 += 360; double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*radius); double hs = factorY(2*radius); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.draw(new Arc2D.Double(xs - ws/2, ys - hs/2, ws, hs, angle1, angle2 - angle1, Arc2D.OPEN)); draw(); } /** * Draws a square of the specified size, centered at (x, y). * * @param x the x-coordinate of the center of the square * @param y the y-coordinate of the center of the square * @param halfLength one half the length of any side of the square * @throws IllegalArgumentException if {@code halfLength} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void square(double x, double y, double halfLength) { validate(x, "x"); validate(y, "y"); validate(halfLength, "halfLength"); validateNonnegative(halfLength, "half length"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*halfLength); double hs = factorY(2*halfLength); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.draw(new Rectangle2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a square of the specified size, centered at (x, y). * * @param x the x-coordinate of the center of the square * @param y the y-coordinate of the center of the square * @param halfLength one half the length of any side of the square * @throws IllegalArgumentException if {@code halfLength} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void filledSquare(double x, double y, double halfLength) { validate(x, "x"); validate(y, "y"); validate(halfLength, "halfLength"); validateNonnegative(halfLength, "half length"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*halfLength); double hs = factorY(2*halfLength); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.fill(new Rectangle2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a rectangle of the specified size, centered at (x, y). * * @param x the x-coordinate of the center of the rectangle * @param y the y-coordinate of the center of the rectangle * @param halfWidth one half the width of the rectangle * @param halfHeight one half the height of the rectangle * @throws IllegalArgumentException if either {@code halfWidth} or {@code halfHeight} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void rectangle(double x, double y, double halfWidth, double halfHeight) { validate(x, "x"); validate(y, "y"); validate(halfWidth, "halfWidth"); validate(halfHeight, "halfHeight"); validateNonnegative(halfWidth, "half width"); validateNonnegative(halfHeight, "half height"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*halfWidth); double hs = factorY(2*halfHeight); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.draw(new Rectangle2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a filled rectangle of the specified size, centered at (x, y). * * @param x the x-coordinate of the center of the rectangle * @param y the y-coordinate of the center of the rectangle * @param halfWidth one half the width of the rectangle * @param halfHeight one half the height of the rectangle * @throws IllegalArgumentException if either {@code halfWidth} or {@code halfHeight} is negative * @throws IllegalArgumentException if any argument is either NaN or infinite */ public void filledRectangle(double x, double y, double halfWidth, double halfHeight) { validate(x, "x"); validate(y, "y"); validate(halfWidth, "halfWidth"); validate(halfHeight, "halfHeight"); validateNonnegative(halfWidth, "half width"); validateNonnegative(halfHeight, "half height"); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(2*halfWidth); double hs = factorY(2*halfHeight); if (ws <= 1 && hs <= 1) pixel(x, y); else offscreen.fill(new Rectangle2D.Double(xs - ws/2, ys - hs/2, ws, hs)); draw(); } /** * Draws a polygon with the vertices * (x₀, y₀), * (x₁, y₁), ..., * (x_n–1, y_n–1). * * @param x an array of all the x-coordinates of the polygon * @param y an array of all the y-coordinates of the polygon * @throws IllegalArgumentException unless {@code x[]} and {@code y[]} * are of the same length * @throws IllegalArgumentException if any coordinate is either NaN or infinite * @throws IllegalArgumentException if either {@code x[]} or {@code y[]} is {@code null} */ public void polygon(double[] x, double[] y) { validateNotNull(x, "x-coordinate array"); validateNotNull(y, "y-coordinate array"); for (int i = 0; i < x.length; i++) validate(x[i], "x[" + i + "]"); for (int i = 0; i < y.length; i++) validate(y[i], "y[" + i + "]"); int n1 = x.length; int n2 = y.length; if (n1 != n2) throw new IllegalArgumentException("arrays must be of the same length"); int n = n1; if (n == 0) return; GeneralPath path = new GeneralPath(); path.moveTo((float) scaleX(x[0]), (float) scaleY(y[0])); for (int i = 0; i < n; i++) path.lineTo((float) scaleX(x[i]), (float) scaleY(y[i])); path.closePath(); offscreen.draw(path); draw(); } /** * Draws a filled polygon with the vertices * (x₀, y₀), * (x₁, y₁), ..., * (x_n–1, y_n–1). * * @param x an array of all the x-coordinates of the polygon * @param y an array of all the y-coordinates of the polygon * @throws IllegalArgumentException unless {@code x[]} and {@code y[]} * are of the same length * @throws IllegalArgumentException if any coordinate is either NaN or infinite * @throws IllegalArgumentException if either {@code x[]} or {@code y[]} is {@code null} */ public void filledPolygon(double[] x, double[] y) { validateNotNull(x, "x-coordinate array"); validateNotNull(y, "y-coordinate array"); for (int i = 0; i < x.length; i++) validate(x[i], "x[" + i + "]"); for (int i = 0; i < y.length; i++) validate(y[i], "y[" + i + "]"); int n1 = x.length; int n2 = y.length; if (n1 != n2) throw new IllegalArgumentException("arrays must be of the same length"); int n = n1; if (n == 0) return; GeneralPath path = new GeneralPath(); path.moveTo((float) scaleX(x[0]), (float) scaleY(y[0])); for (int i = 0; i < n; i++) path.lineTo((float) scaleX(x[i]), (float) scaleY(y[i])); path.closePath(); offscreen.fill(path); draw(); } /*************************************************************************** * Drawing images. ***************************************************************************/ // get an image from the given filename private static Image getImage(String filename) { if (filename == null) throw new IllegalArgumentException(); // to read from file ImageIcon icon = new ImageIcon(filename); // try to read from URL if (icon.getImageLoadStatus() != MediaTracker.COMPLETE) { try { URI uri = new URI(filename); if (uri.isAbsolute()) { URL url = uri.toURL(); icon = new ImageIcon(url); } } catch (MalformedURLException | URISyntaxException e) { /* not a url */ } } // in case file is inside a .jar (classpath relative to Draw) if (icon.getImageLoadStatus() != MediaTracker.COMPLETE) { URL url = Draw.class.getResource(filename); if (url != null) icon = new ImageIcon(url); } // in case file is inside a .jar (classpath relative to root of jar) if (icon.getImageLoadStatus() != MediaTracker.COMPLETE) { URL url = Draw.class.getResource("/" + filename); if (url == null) throw new IllegalArgumentException("could not read image: '" + filename + "'"); icon = new ImageIcon(url); } return icon.getImage(); } /** * Draws the specified image centered at (x, y). * The supported image formats are typically JPEG, PNG, GIF, TIFF, and BMP. * As an optimization, the picture is cached, so there is no performance * penalty for redrawing the same image multiple times (e.g., in an animation). * However, if you change the picture file after drawing it, subsequent * calls will draw the original picture. * * @param x the center x-coordinate of the image * @param y the center y-coordinate of the image * @param filename the name of the image/picture, e.g., "ball.gif" * @throws IllegalArgumentException if the image filename is invalid * @throws IllegalArgumentException if either {@code x} or {@code y} is either NaN or infinite */ public void picture(double x, double y, String filename) { validate(x, "x"); validate(y, "y"); validateNotNull(filename, "filename"); Image image = getImage(filename); double xs = scaleX(x); double ys = scaleY(y); int ws = image.getWidth(null); int hs = image.getHeight(null); if (ws < 0 || hs < 0) throw new IllegalArgumentException("image " + filename + " is corrupt"); offscreen.drawImage(image, (int) Math.round(xs - ws/2.0), (int) Math.round(ys - hs/2.0), null); draw(); } /** * Draws the specified image centered at (x, y), * rotated given number of degrees. * The supported image formats are typically JPEG, PNG, GIF, TIFF, and BMP. * * @param x the center x-coordinate of the image * @param y the center y-coordinate of the image * @param filename the name of the image/picture, e.g., "ball.gif" * @param degrees is the number of degrees to rotate counterclockwise * @throws IllegalArgumentException if the image filename is invalid * @throws IllegalArgumentException if {@code x}, {@code y}, {@code degrees} is NaN or infinite * @throws IllegalArgumentException if {@code filename} is {@code null} */ public void picture(double x, double y, String filename, double degrees) { validate(x, "x"); validate(y, "y"); validate(degrees, "degrees"); validateNotNull(filename, "filename"); Image image = getImage(filename); double xs = scaleX(x); double ys = scaleY(y); int ws = image.getWidth(null); int hs = image.getHeight(null); if (ws < 0 || hs < 0) throw new IllegalArgumentException("image " + filename + " is corrupt"); offscreen.rotate(Math.toRadians(-degrees), xs, ys); offscreen.drawImage(image, (int) Math.round(xs - ws/2.0), (int) Math.round(ys - hs/2.0), null); offscreen.rotate(Math.toRadians(+degrees), xs, ys); draw(); } /** * Draws the specified image centered at (x, y), * rescaled to the specified bounding box. * The supported image formats are typically JPEG, PNG, GIF, TIFF, and BMP. * * @param x the center x-coordinate of the image * @param y the center y-coordinate of the image * @param filename the name of the image/picture, e.g., "ball.gif" * @param scaledWidth the width of the scaled image (in screen coordinates) * @param scaledHeight the height of the scaled image (in screen coordinates) * @throws IllegalArgumentException if either {@code scaledWidth} * or {@code scaledHeight} is negative * @throws IllegalArgumentException if the image filename is invalid * @throws IllegalArgumentException if {@code x} or {@code y} is either NaN or infinite * @throws IllegalArgumentException if {@code filename} is {@code null} */ public void picture(double x, double y, String filename, double scaledWidth, double scaledHeight) { validate(x, "x"); validate(y, "y"); validate(scaledWidth, "scaled width"); validate(scaledHeight, "scaled height"); validateNotNull(filename, "filename"); validateNonnegative(scaledWidth, "scaled width"); validateNonnegative(scaledHeight, "scaled height"); Image image = getImage(filename); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(scaledWidth); double hs = factorY(scaledHeight); if (ws < 0 || hs < 0) throw new IllegalArgumentException("image " + filename + " is corrupt"); if (ws <= 1 && hs <= 1) pixel(x, y); else { offscreen.drawImage(image, (int) Math.round(xs - ws/2.0), (int) Math.round(ys - hs/2.0), (int) Math.round(ws), (int) Math.round(hs), null); } draw(); } /** * Draws the specified image centered at (x, y), rotated * given number of degrees, and rescaled to the specified bounding box. * The supported image formats are typically JPEG, PNG, GIF, TIFF, and BMP. * * @param x the center x-coordinate of the image * @param y the center y-coordinate of the image * @param filename the name of the image/picture, e.g., "ball.gif" * @param scaledWidth the width of the scaled image (in screen coordinates) * @param scaledHeight the height of the scaled image (in screen coordinates) * @param degrees is the number of degrees to rotate counterclockwise * @throws IllegalArgumentException if either {@code scaledWidth} * or {@code scaledHeight} is negative * @throws IllegalArgumentException if the image filename is invalid */ public void picture(double x, double y, String filename, double scaledWidth, double scaledHeight, double degrees) { validate(x, "x"); validate(y, "y"); validate(scaledWidth, "scaled width"); validate(scaledHeight, "scaled height"); validate(degrees, "degrees"); validateNotNull(filename, "filename"); validateNonnegative(scaledWidth, "scaled width"); validateNonnegative(scaledHeight, "scaled height"); Image image = getImage(filename); double xs = scaleX(x); double ys = scaleY(y); double ws = factorX(scaledWidth); double hs = factorY(scaledHeight); if (ws < 0 || hs < 0) throw new IllegalArgumentException("image " + filename + " is corrupt"); if (ws <= 1 && hs <= 1) pixel(x, y); offscreen.rotate(Math.toRadians(-degrees), xs, ys); offscreen.drawImage(image, (int) Math.round(xs - ws/2.0), (int) Math.round(ys - hs/2.0), (int) Math.round(ws), (int) Math.round(hs), null); offscreen.rotate(Math.toRadians(+degrees), xs, ys); draw(); } /*************************************************************************** * Drawing text. ***************************************************************************/ /** * Writes the given text string in the current font, centered at (x, y). * * @param x the center x-coordinate of the text * @param y the center y-coordinate of the text * @param text the text to write * @throws IllegalArgumentException if {@code text} is {@code null} * @throws IllegalArgumentException if {@code x} or {@code y} is either NaN or infinite */ public void text(double x, double y, String text) { validate(x, "x"); validate(y, "y"); validateNotNull(text, "text"); offscreen.setFont(font); FontMetrics metrics = offscreen.getFontMetrics(); double xs = scaleX(x); double ys = scaleY(y); int ws = metrics.stringWidth(text); int hs = metrics.getDescent(); offscreen.drawString(text, (float) (xs - ws/2.0), (float) (ys + hs)); draw(); } /** * Writes the given text string in the current font, centered at (x, y) and * rotated by the specified number of degrees. * @param x the center x-coordinate of the text * @param y the center y-coordinate of the text * @param text the text to write * @param degrees is the number of degrees to rotate counterclockwise * @throws IllegalArgumentException if {@code text} is {@code null} * @throws IllegalArgumentException if {@code x}, {@code y}, or {@code degrees} is either NaN or infinite */ public void text(double x, double y, String text, double degrees) { validate(x, "x"); validate(y, "y"); validate(degrees, "degrees"); validateNotNull(text, "text"); double xs = scaleX(x); double ys = scaleY(y); offscreen.rotate(Math.toRadians(-degrees), xs, ys); text(x, y, text); offscreen.rotate(Math.toRadians(+degrees), xs, ys); } /** * Writes the given text string in the current font, left-aligned at (x, y). * @param x the x-coordinate of the text * @param y the y-coordinate of the text * @param text the text * @throws IllegalArgumentException if {@code text} is {@code null} * @throws IllegalArgumentException if {@code x} or {@code y} is either NaN or infinite */ public void textLeft(double x, double y, String text) { validate(x, "x"); validate(y, "y"); validateNotNull(text, "text"); offscreen.setFont(font); FontMetrics metrics = offscreen.getFontMetrics(); double xs = scaleX(x); double ys = scaleY(y); // int ws = metrics.stringWidth(text); int hs = metrics.getDescent(); offscreen.drawString(text, (float) xs, (float) (ys + hs)); draw(); } /** * Writes the given text string in the current font, right-aligned at (x, y). * * @param x the x-coordinate of the text * @param y the y-coordinate of the text * @param text the text to write * @throws IllegalArgumentException if {@code text} is {@code null} * @throws IllegalArgumentException if {@code x} or {@code y} is either NaN or infinite */ public void textRight(double x, double y, String text) { validate(x, "x"); validate(y, "y"); validateNotNull(text, "text"); offscreen.setFont(font); FontMetrics metrics = offscreen.getFontMetrics(); double xs = scaleX(x); double ys = scaleY(y); int ws = metrics.stringWidth(text); int hs = metrics.getDescent(); offscreen.drawString(text, (float) (xs - ws), (float) (ys + hs)); draw(); } /** * Copies the offscreen buffer to the onscreen buffer, pauses for t milliseconds * and enables double buffering. * @param t number of milliseconds * @throws IllegalArgumentException if {@code t} is negative * @deprecated replaced by {@link #enableDoubleBuffering()}, {@link #show()}, and {@link #pause(int t)} */ @Deprecated public void show(int t) { show(); pause(t); enableDoubleBuffering(); } /** * Pause for t milliseconds. This method is intended to support computer animations. * @param t number of milliseconds * @throws IllegalArgumentException if {@code t} is negative */ public void pause(int t) { try { Thread.sleep(t); } catch (InterruptedException e) { System.out.println("Error sleeping"); } } /** * Copies offscreen buffer to onscreen buffer. There is no reason to call * this method unless double buffering is enabled. */ public void show() { onscreen.setBackground(backgroundColor); onscreen.clearRect(0, 0, 2*width, 2*height); onscreen.drawImage(offscreenImage, 0, 0, null); // make frame visible upon first call to show() if (frame.isVisible() != isJFrameVisible) { frame.setVisible(isJFrameVisible); } frame.repaint(); } // draw onscreen if defer is false private void draw() { if (!defer) show(); } /** * Enable double buffering. All subsequent calls to * drawing methods such as {@code line()}, {@code circle()}, * and {@code square()} will be deferred until the next call * to show(). Useful for animations. */ public void enableDoubleBuffering() { defer = true; } /** * Disable double buffering. All subsequent calls to * drawing methods such as {@code line()}, {@code circle()}, * and {@code square()} will be displayed on screen when called. * This is the default. */ public void disableDoubleBuffering() { defer = false; } /** * Saves the drawing to a file in a supported file format * (typically JPEG, PNG, GIF, TIFF, and BMP). * The filetype extension must be {@code .jpg}, {@code .png}, {@code .gif}, * {@code .bmp}, or {@code .tif}. * * @param filename the name of the file * @throws IllegalArgumentException if {@code filename} is {@code null} * @throws IllegalArgumentException if {@code filename} is the empty string * @throws IllegalArgumentException if {@code filename} has invalid filetype extension * @throws IllegalArgumentException if cannot write the file {@code filename} */ public void save(String filename) { validateNotNull(filename, "filename"); if (filename.length() == 0) { throw new IllegalArgumentException("argument to save() is the empty string"); } File file = new File(filename); String suffix = filename.substring(filename.lastIndexOf('.') + 1); if (!filename.contains(".") || suffix.length() == 0) { throw new IllegalArgumentException("the filename '" + filename + "' has no file extension, such as .jpg or .png"); } try { // if the file format supports transparency (such as PNG or GIF) if (ImageIO.write(onscreenImage, suffix, file)) return; // if the file format does not support transparency (such as JPEG or BMP) BufferedImage saveImage = new BufferedImage(2*width, 2*height, BufferedImage.TYPE_INT_RGB); saveImage.createGraphics().drawImage(onscreenImage, 0, 0, Color.WHITE, null); if (ImageIO.write(saveImage, suffix, file)) return; // failed to save the file; probably wrong format throw new IllegalArgumentException("the filetype '" + suffix + "' is not supported"); } catch (IOException e) { throw new IllegalArgumentException("could not write the file + " + filename, e); } } /** * This method cannot be called directly. */ @Override public void actionPerformed(ActionEvent event) { FileDialog chooser = new FileDialog(frame, "Use a .png or .jpg extension", FileDialog.SAVE); chooser.setVisible(true); String selectedDirectory = chooser.getDirectory(); String selectedFilename = chooser.getFile(); if (selectedDirectory != null && selectedFilename != null) { try { save(selectedDirectory + selectedFilename); } catch (IllegalArgumentException e) { System.err.println(e.getMessage()); } } } /*************************************************************************** * Event-based interactions. ***************************************************************************/ /** * Adds a {@link DrawListener} to listen to keyboard and mouse events. * * @param listener the {\tt DrawListener} argument */ public void addListener(DrawListener listener) { // ensure there is a window for listening to events show(); listeners.add(listener); } /*************************************************************************** * Mouse interactions. ***************************************************************************/ /** * Returns true if the mouse is being pressed. * * @return {@code true} if the mouse is being pressed; * {@code false} otherwise */ public boolean isMousePressed() { synchronized (mouseLock) { return isMousePressed; } } /** * Returns true if the mouse is being pressed. * * @return {@code true} if the mouse is being pressed; * {@code false} otherwise * @deprecated replaced by {@link #isMousePressed()} */ @Deprecated public boolean mousePressed() { synchronized (mouseLock) { return isMousePressed; } } /** * Returns the x-coordinate of the mouse. * @return the x-coordinate of the mouse */ public double mouseX() { synchronized (mouseLock) { return mouseX; } } /** * Returns the y-coordinate of the mouse. * * @return the y-coordinate of the mouse */ public double mouseY() { synchronized (mouseLock) { return mouseY; } } /** * This method cannot be called directly. */ @Override public void mouseEntered(MouseEvent event) { // this body is intentionally left empty } /** * This method cannot be called directly. */ @Override public void mouseExited(MouseEvent event) { // this body is intentionally left empty } /** * This method cannot be called directly. */ @Override public void mousePressed(MouseEvent event) { synchronized (mouseLock) { mouseX = userX(event.getX()); mouseY = userY(event.getY()); isMousePressed = true; } if (event.getButton() == MouseEvent.BUTTON1) { for (DrawListener listener : listeners) listener.mousePressed(userX(event.getX()), userY(event.getY())); } } /** * This method cannot be called directly. */ @Override public void mouseReleased(MouseEvent event) { synchronized (mouseLock) { isMousePressed = false; } if (event.getButton() == MouseEvent.BUTTON1) { for (DrawListener listener : listeners) listener.mouseReleased(userX(event.getX()), userY(event.getY())); } } /** * This method cannot be called directly. */ @Override public void mouseClicked(MouseEvent event) { if (event.getButton() == MouseEvent.BUTTON1) { for (DrawListener listener : listeners) listener.mouseClicked(userX(event.getX()), userY(event.getY())); } } /** * This method cannot be called directly. */ @Override public void mouseDragged(MouseEvent event) { synchronized (mouseLock) { mouseX = userX(event.getX()); mouseY = userY(event.getY()); } // doesn't seem to work if a button is specified for (DrawListener listener : listeners) listener.mouseDragged(userX(event.getX()), userY(event.getY())); } /** * This method cannot be called directly. */ @Override public void mouseMoved(MouseEvent event) { synchronized (mouseLock) { mouseX = userX(event.getX()); mouseY = userY(event.getY()); } } /*************************************************************************** * Keyboard interactions. ***************************************************************************/ /** * Returns true if the user has typed a key. * * @return {@code true} if the user has typed a key; {@code false} otherwise */ public boolean hasNextKeyTyped() { synchronized (keyLock) { return !keysTyped.isEmpty(); } } /** * The next key typed by the user. * * @return the next key typed by the user */ public char nextKeyTyped() { synchronized (keyLock) { return keysTyped.removeLast(); } } /** * Returns true if the keycode is being pressed. *

* This method takes as an argument the keycode (corresponding to a physical key). * It can handle action keys (such as F1 and arrow keys) and modifier keys * (such as shift and control). * See {@link KeyEvent} for a description of key codes. * * @param keycode the keycode to check * @return {@code true} if {@code keycode} is currently being pressed; * {@code false} otherwise */ public boolean isKeyPressed(int keycode) { synchronized (keyLock) { return keysDown.contains(keycode); } } /** * This method cannot be called directly. */ @Override public void keyTyped(KeyEvent event) { synchronized (keyLock) { keysTyped.addFirst(event.getKeyChar()); } // notify all listeners for (DrawListener listener : listeners) listener.keyTyped(event.getKeyChar()); } /** * This method cannot be called directly. */ @Override public void keyPressed(KeyEvent event) { synchronized (keyLock) { keysDown.add(event.getKeyCode()); } // notify all listeners for (DrawListener listener : listeners) listener.keyPressed(event.getKeyCode()); } /** * This method cannot be called directly. */ @Override public void keyReleased(KeyEvent event) { synchronized (keyLock) { keysDown.remove(event.getKeyCode()); } // notify all listeners for (DrawListener listener : listeners) listener.keyReleased(event.getKeyCode()); } /*************************************************************************** * Timer events. ***************************************************************************/ /** * Sets a timer that calls update() method a specified number of times * per second. *

* @param callsPerSecond calls per second */ public void enableTimer(int callsPerSecond) { disableTimer(); timer = new Timer(); timer.schedule(new MyTimerTask(), 0, (int) Math.round(1000.0 / callsPerSecond)); } public void disableTimer() { if (timer != null) timer.cancel(); } private class MyTimerTask extends TimerTask { public void run() { for (DrawListener listener : listeners) listener.update(); } } /*************************************************************************** * For improved resolution on Mac Retina displays. ***************************************************************************/ private static class RetinaImageIcon extends ImageIcon { public RetinaImageIcon(Image image) { super(image); } public int getIconWidth() { return super.getIconWidth() / 2; } /** * Returns the height of the icon. * * @return the height in pixels of this icon */ public int getIconHeight() { return super.getIconHeight() / 2; } public synchronized void paintIcon(Component c, Graphics g, int x, int y) { Graphics2D g2 = (Graphics2D) g.create(); g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC); g2.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2.scale(0.5, 0.5); super.paintIcon(c, g2, x * 2, y * 2); g2.dispose(); } } /** * Test client. * * @param args the command-line arguments */ public static void main(String[] args) { // create one drawing window Draw draw1 = new Draw(); draw1.setTitle("Test client 1"); draw1.square(0.2, 0.8, 0.1); draw1.filledSquare(0.8, 0.8, 0.2); draw1.circle(0.8, 0.2, 0.2); draw1.setPenColor(Draw.MAGENTA); draw1.setPenRadius(0.02); draw1.arc(0.8, 0.2, 0.1, 200, 45); // create another one Draw draw2 = new Draw(); draw2.setCanvasSize(900, 200); draw2.setTitle("Test client 2"); // draw a blue diamond draw2.setPenRadius(); draw2.setPenColor(Draw.BLUE); double[] x = { 0.1, 0.2, 0.3, 0.2 }; double[] y = { 0.2, 0.3, 0.2, 0.1 }; draw2.filledPolygon(x, y); // text draw2.setPenColor(Draw.BLACK); draw2.text(0.2, 0.5, "black text"); draw2.setPenColor(Draw.WHITE); draw2.text(0.2, 0.2, "white text"); } }