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StdDraw.java
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package conwaygame;
/******************************************************************************
* Compilation: javac StdDraw.java
* Execution: java StdDraw
* Dependencies: none
*
* Standard 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 geometric shapes (e.g.,
* points, lines, circles, rectangles) in a window on your computer
* and to save the drawings to a file.
*
* Todo
* ----
* - Add support for gradient fill, etc.
* - Fix setCanvasSize() so that it can be called only once.
* - Should setCanvasSize() reset xScale(), yScale(), penRadius(),
* penColor(), and font()
* - On some systems, drawing a line (or other shape) that extends way
* beyond canvas (e.g., to infinity) dimensions does not get drawn.
*
* Remarks
* -------
* - don't use AffineTransform for rescaling since it inverts
* images and strings
*
******************************************************************************/
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.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.awt.image.DirectColorModel;
import java.awt.image.WritableRaster;
import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.LinkedList;
import java.util.TreeSet;
import java.util.NoSuchElementException;
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 {@code StdDraw} 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, squares,
* circles, and other geometric shapes in a window on your computer and
* to save the drawings to a file. Standard drawing also includes
* facilities for text, color, pictures, and animation, along with
* user interaction via the keyboard and mouse.
* <p>
* <b>Getting started.</b>
* To use this class, you must have {@code StdDraw.class} in your
* Java classpath. If you used our autoinstaller, you should be all set.
* Otherwise, either download
* <a href = "https://introcs.cs.princeton.edu/java/code/stdlib.jar">stdlib.jar</a>
* and add to your Java classpath or download
* <a href = "https://introcs.cs.princeton.edu/java/stdlib/StdDraw.java">StdDraw.java</a>
* and put a copy in your working directory.
* <p>
* Now, cut-and-paste the following short program into your editor:
* <pre>
* public class TestStdDraw {
* public static void main(String[] args) {
* StdDraw.setPenRadius(0.05);
* StdDraw.setPenColor(StdDraw.BLUE);
* StdDraw.point(0.5, 0.5);
* StdDraw.setPenColor(StdDraw.MAGENTA);
* StdDraw.line(0.2, 0.2, 0.8, 0.2);
* }
* }
* </pre>
* If you compile and execute the program, you should see a window
* appear with a thick magenta line and a blue point.
* This program illustrates the two main types of methods in standard
* drawing—methods that draw geometric shapes and methods that
* control drawing parameters.
* The methods {@code StdDraw.line()} and {@code StdDraw.point()}
* draw lines and points; the methods {@code StdDraw.setPenRadius()}
* and {@code StdDraw.setPenColor()} control the line thickness and color.
* <p>
* <b>Points and lines.</b>
* You can draw points and line segments with the following methods:
* <ul>
* <li> {@link #point(double x, double y)}
* <li> {@link #line(double x1, double y1, double x2, double y2)}
* </ul>
* <p>
* The <em>x</em>- and <em>y</em>-coordinates must be in the drawing area
* (between 0 and 1 and by default) or the points and lines will not be visible.
* <p>
* <b>Squares, circles, rectangles, and ellipses.</b>
* You can draw squares, circles, rectangles, and ellipses using
* the following methods:
* <ul>
* <li> {@link #circle(double x, double y, double radius)}
* <li> {@link #ellipse(double x, double y, double semiMajorAxis, double semiMinorAxis)}
* <li> {@link #square(double x, double y, double halfLength)}
* <li> {@link #rectangle(double x, double y, double halfWidth, double halfHeight)}
* </ul>
* <p>
* All of these methods take as arguments the location and size of the shape.
* The location is always specified by the <em>x</em>- and <em>y</em>-coordinates
* of its <em>center</em>.
* The size of a circle is specified by its radius and the size of an ellipse is
* specified by the lengths of its semi-major and semi-minor axes.
* The size of a square or rectangle is specified by its half-width or half-height.
* The convention for drawing squares and rectangles is parallel to those for
* drawing circles and ellipses, but may be unexpected to the uninitiated.
* <p>
* The methods above trace outlines of the given shapes. The following methods
* draw filled versions:
* <ul>
* <li> {@link #filledCircle(double x, double y, double radius)}
* <li> {@link #filledEllipse(double x, double y, double semiMajorAxis, double semiMinorAxis)}
* <li> {@link #filledSquare(double x, double y, double radius)}
* <li> {@link #filledRectangle(double x, double y, double halfWidth, double halfHeight)}
* </ul>
* <p>
* <b>Circular arcs.</b>
* You can draw circular arcs with the following method:
* <ul>
* <li> {@link #arc(double x, double y, double radius, double angle1, double angle2)}
* </ul>
* <p>
* The arc is from the circle centered at (<em>x</em>, <em>y</em>) of the specified radius.
* The arc extends from angle1 to angle2. By convention, the angles are
* <em>polar</em> (counterclockwise angle from the <em>x</em>-axis)
* and represented in degrees. For example, {@code StdDraw.arc(0.0, 0.0, 1.0, 0, 90)}
* draws the arc of the unit circle from 3 o'clock (0 degrees) to 12 o'clock (90 degrees).
* <p>
* <b>Polygons.</b>
* You can draw polygons with the following methods:
* <ul>
* <li> {@link #polygon(double[] x, double[] y)}
* <li> {@link #filledPolygon(double[] x, double[] y)}
* </ul>
* <p>
* The points in the polygon are ({@code x[i]}, {@code y[i]}).
* For example, the following code fragment draws a filled diamond
* with vertices (0.1, 0.2), (0.2, 0.3), (0.3, 0.2), and (0.2, 0.1):
* <pre>
* double[] x = { 0.1, 0.2, 0.3, 0.2 };
* double[] y = { 0.2, 0.3, 0.2, 0.1 };
* StdDraw.filledPolygon(x, y);
* </pre>
* <p>
* <b>Pen size.</b>
* The pen is circular, so that when you set the pen radius to <em>r</em>
* and draw a point, you get a circle of radius <em>r</em>. Also, lines are
* of thickness 2<em>r</em> and have rounded ends. The default pen radius
* is 0.005 and is not affected by coordinate scaling. This default pen
* radius is about 1/200 the width of the default canvas, so that if
* you draw 100 points equally spaced along a horizontal or vertical line,
* you will be able to see individual circles, but if you draw 200 such
* points, the result will look like a line.
* <ul>
* <li> {@link #setPenRadius(double radius)}
* </ul>
* <p>
* For example, {@code StdDraw.setPenRadius(0.025)} makes
* the thickness of the lines and the size of the points to be five times
* the 0.005 default.
* To draw points with the minimum possible radius (one pixel on typical
* displays), set the pen radius to 0.0.
* <p>
* <b>Pen color.</b>
* All geometric shapes (such as points, lines, and circles) are drawn using
* the current pen color. By default, it is black.
* You can change the pen color with the following methods:
* <ul>
* <li> {@link #setPenColor(int red, int green, int blue)}
* <li> {@link #setPenColor(Color color)}
* </ul>
* <p>
* The first method allows you to specify colors using the RGB color system.
* This <a href = "http://johndyer.name/lab/colorpicker/">color picker</a>
* is a convenient way to find a desired color.
* <p>
* The second method allows you to specify colors using the
* {@link Color} data type, which is defined in Java's {@link java.awt} pacakge.
* A number of colors are predefined in standard drawing:
* {@link #BLACK}, {@link #BLUE}, {@link #CYAN}, {@link #DARK_GRAY}, {@link #GRAY},
* {@link #GREEN}, {@link #LIGHT_GRAY}, {@link #MAGENTA}, {@link #ORANGE},
* {@link #PINK}, {@link #RED}, {@link #WHITE}, {@link #YELLOW},
* {@link #BOOK_BLUE}, {@link #BOOK_LIGHT_BLUE}, {@link #BOOK_RED}, and
* {@link #PRINCETON_ORANGE}.
* For example, {@code StdDraw.setPenColor(StdDraw.MAGENTA)} sets the
* pen color to magenta.
* <p>
* <b>Canvas size.</b>
* By default, all drawing takes places in a 512-by-512 canvas.
* The canvas does not include the window title or window border.
* You can change the size of the canvas with the following method:
* <ul>
* <li> {@link #setCanvasSize(int width, int height)}
* </ul>
* <p>
* This sets the canvas size to be <em>width</em>-by-<em>height</em> pixels.
* It also erases the current drawing and resets the coordinate system,
* pen radius, pen color, and font back to their default values.
* Ordinarly, this method is called only once, at the very beginning of a program.
* For example, {@code StdDraw.setCanvasSize(800, 800)}
* sets the canvas size to be 800-by-800 pixels.
* <p>
* <b>Canvas scale and coordinate system.</b>
* By default, all drawing takes places in the unit square, with (0, 0) at
* lower left and (1, 1) at upper right. You can change the default
* coordinate system with the following methods:
* <ul>
* <li> {@link #setXscale(double xmin, double xmax)}
* <li> {@link #setYscale(double ymin, double ymax)}
* <li> {@link #setScale(double min, double max)}
* </ul>
* <p>
* The arguments are the coordinates of the minimum and maximum
* <em>x</em>- or <em>y</em>-coordinates that will appear in the canvas.
* For example, if you wish to use the default coordinate system but
* leave a small margin, you can call {@code StdDraw.setScale(-.05, 1.05)}.
* <p>
* These methods change the coordinate system for subsequent drawing
* commands; they do not affect previous drawings.
* These methods do not change the canvas size; so, if the <em>x</em>-
* and <em>y</em>-scales are different, squares will become rectangles
* and circles will become ellipses.
* <p>
* <b>Text.</b>
* You can use the following methods to annotate your drawings with text:
* <ul>
* <li> {@link #text(double x, double y, String text)}
* <li> {@link #text(double x, double y, String text, double degrees)}
* <li> {@link #textLeft(double x, double y, String text)}
* <li> {@link #textRight(double x, double y, String text)}
* </ul>
* <p>
* The first two methods write the specified text in the current font,
* centered at (<em>x</em>, <em>y</em>).
* The second method allows you to rotate the text.
* The last two methods either left- or right-align the text at (<em>x</em>, <em>y</em>).
* <p>
* The default font is a Sans Serif font with point size 16.
* You can use the following method to change the font:
* <ul>
* <li> {@link #setFont(Font font)}
* </ul>
* <p>
* To specify the font, you use the {@link Font} data type,
* which is defined in Java's {@link java.awt} package.
* This allows you to
* choose the face, size, and style of the font. For example, the following
* code fragment sets the font to Arial Bold, 60 point.
* The <code>import</code> statement allows you to refer to <code>Font</code>
* directly, without needing the fully qualified name <code>java.awt.Font</code>.
* <pre>
* import java.awt.Font;
* ...
* Font font = new Font("Arial", Font.BOLD, 60);
* StdDraw.setFont(font);
* StdDraw.text(0.5, 0.5, "Hello, World");
* </pre>
* <p>
* <b>Images.</b>
* You can use the following methods to add images to your drawings:
* <ul>
* <li> {@link #picture(double x, double y, String filename)}
* <li> {@link #picture(double x, double y, String filename, double degrees)}
* <li> {@link #picture(double x, double y, String filename, double scaledWidth, double scaledHeight)}
* <li> {@link #picture(double x, double y, String filename, double scaledWidth, double scaledHeight, double degrees)}
* </ul>
* <p>
* These methods draw the specified image, centered at (<em>x</em>, <em>y</em>).
* The supported image formats are JPEG, PNG, and GIF.
* The image will display at its native size, independent of the coordinate system.
* Optionally, you can rotate the image a specified number of degrees counterclockwise
* or rescale it to fit snugly inside a width-by-height bounding box.
* <p>
* <b>Saving to a file.</b>
* You save your image to a file using the <em>File → Save</em> menu option.
* You can also save a file programatically using the following method:
* <ul>
* <li> {@link #save(String filename)}
* </ul>
* <p>
* The supported image formats are JPEG and PNG. The filename must have either the
* extension .jpg or .png.
* We recommend using PNG for drawing that consist solely of geometric shapes and JPEG
* for drawings that contains pictures.
* <p>
* <b>Clearing the canvas.</b>
* To clear the entire drawing canvas, you can use the following methods:
* <ul>
* <li> {@link #clear()}
* <li> {@link #clear(Color color)}
* </ul>
* <p>
* The first method clears the canvas to white; the second method
* allows you to specify a color of your choice. For example,
* {@code StdDraw.clear(StdDraw.LIGHT_GRAY)} clears the canvas to a shade
* of gray.
* <p>
* <b>Computer animations and double buffering.</b>
* Double buffering is one of the most powerful features of standard drawing,
* enabling computer animations.
* The following methods control the way in which objects are drawn:
* <ul>
* <li> {@link #enableDoubleBuffering()}
* <li> {@link #disableDoubleBuffering()}
* <li> {@link #show()}
* <li> {@link #pause(int t)}
* </ul>
* <p>
* By default, double buffering is disabled, which means that as soon as you
* call a drawing
* method—such as {@code point()} or {@code line()}—the
* results appear on the screen.
* <p>
* When double buffering is enabled by calling {@link #enableDoubleBuffering()},
* all drawing takes place on the <em>offscreen canvas</em>. The offscreen canvas
* is not displayed. Only when you call
* {@link #show()} does your drawing get copied from the offscreen canvas to
* the onscreen canvas, where it is displayed in the standard drawing window. You
* can think of double buffering as collecting all of the lines, points, shapes,
* and text that you tell it to draw, and then drawing them all
* <em>simultaneously</em>, upon request.
* <p>
* The most important use of double buffering is to produce computer
* animations, creating the illusion of motion by rapidly
* displaying static drawings. To produce an animation, repeat
* the following four steps:
* <ul>
* <li> Clear the offscreen canvas.
* <li> Draw objects on the offscreen canvas.
* <li> Copy the offscreen canvas to the onscreen canvas.
* <li> Wait for a short while.
* </ul>
* <p>
* The {@link #clear()}, {@link #show()}, and {@link #pause(int t)} methods
* support the first, third, and fourth of these steps, respectively.
* <p>
* For example, this code fragment animates two balls moving in a circle.
* <pre>
* StdDraw.setScale(-2, +2);
* StdDraw.enableDoubleBuffering();
*
* for (double t = 0.0; true; t += 0.02) {
* double x = Math.sin(t);
* double y = Math.cos(t);
* StdDraw.clear();
* StdDraw.filledCircle(x, y, 0.05);
* StdDraw.filledCircle(-x, -y, 0.05);
* StdDraw.show();
* StdDraw.pause(20);
* }
* </pre>
* <p>
* <b>Keyboard and mouse inputs.</b>
* Standard drawing has very basic support for keyboard and mouse input.
* It is much less powerful than most user interface libraries provide, but also much simpler.
* You can use the following methods to intercept mouse events:
* <ul>
* <li> {@link #isMousePressed()}
* <li> {@link #mouseX()}
* <li> {@link #mouseY()}
* </ul>
* <p>
* The first method tells you whether a mouse button is currently being pressed.
* The last two methods tells you the <em>x</em>- and <em>y</em>-coordinates of the mouse's
* current position, using the same coordinate system as the canvas (the unit square, by default).
* You should use these methods in an animation loop that waits a short while before trying
* to poll the mouse for its current state.
* You can use the following methods to intercept keyboard events:
* <ul>
* <li> {@link #hasNextKeyTyped()}
* <li> {@link #nextKeyTyped()}
* <li> {@link #isKeyPressed(int keycode)}
* </ul>
* <p>
* If the user types lots of keys, they will be saved in a list until you process them.
* The first method tells you whether the user has typed a key (that your program has
* not yet processed).
* The second method returns the next key that the user typed (that your program has
* not yet processed) and removes it from the list of saved keystrokes.
* The third method tells you whether a key is currently being pressed.
* <p>
* <b>Accessing control parameters.</b>
* You can use the following methods to access the current pen color, pen radius,
* and font:
* <ul>
* <li> {@link #getPenColor()}
* <li> {@link #getPenRadius()}
* <li> {@link #getFont()}
* </ul>
* <p>
* These methods are useful when you want to temporarily change a
* control parameter and, later, reset it back to its original value.
* <p>
* <b>Corner cases.</b>
* Here are some corner cases.
* <ul>
* <li> Drawing an object outside (or partly outside) the canvas is permitted.
* However, only the part of the object that appears inside the canvas
* will be visible.
* <li> Due to floating-point issues, an object drawn with an <em>x</em>- or
* <em>y</em>-coordinate that is way outside the canvas (such as the line segment
* from (0.5, –10^308) to (0.5, 10^308) may not be visible even in the
* part of the canvas where it should be.
* <li> Any method that is passed a {@code null} argument will throw an
* {@link IllegalArgumentException}.
* <li> Any method that is passed a {@link Double#NaN},
* {@link Double#POSITIVE_INFINITY}, or {@link Double#NEGATIVE_INFINITY}
* argument will throw an {@link IllegalArgumentException}.
* </ul>
* <p>
* <b>Performance tricks.</b>
* Standard drawing is capable of drawing large amounts of data.
* Here are a few tricks and tips:
* <ul>
* <li> Use <em>double buffering</em> for static drawing with a large
* number of objects.
* That is, call {@link #enableDoubleBuffering()} before
* the sequence of drawing commands and call {@link #show()} afterwards.
* Incrementally displaying a complex drawing while it is being
* created can be intolerably inefficient on many computer systems.
* <li> When drawing computer animations, call {@code show()}
* only once per frame, not after drawing each individual object.
* <li> If you call {@code picture()} multiple times with the same filename,
* Java will cache the image, so you do not incur the cost of reading
* from a file each time.
* </ul>
* <p>
* <b>Known bugs and issues.</b>
* <ul>
* <li> The {@code picture()} methods may not draw the portion of the image that is
* inside the canvas if the center point (<em>x</em>, <em>y</em>) is outside the
* canvas.
* This bug appears only on some systems.
* </ul>
* <p>
* <b>Reference.</b>
* For additional documentation,
* see <a href="https://introcs.cs.princeton.edu/15inout">Section 1.5</a> of
* <em>Computer Science: An Interdisciplinary Approach</em>
* by Robert Sedgewick and Kevin Wayne.
*
* @author Robert Sedgewick
* @author Kevin Wayne
*/
public final class StdDraw implements ActionListener, MouseListener, MouseMotionListener, KeyListener {
/**
* The color black.
*/
public static final Color BLACK = Color.BLACK;
/**
* The color blue.
*/
public static final Color BLUE = Color.BLUE;
/**
* The color cyan.
*/
public static final Color CYAN = Color.CYAN;
/**
* The color dark gray.
*/
public static final Color DARK_GRAY = Color.DARK_GRAY;
/**
* The color gray.
*/
public static final Color GRAY = Color.GRAY;
/**
* The color green.
*/
public static final Color GREEN = Color.GREEN;
/**
* The color light gray.
*/
public static final Color LIGHT_GRAY = Color.LIGHT_GRAY;
/**
* The color magenta.
*/
public static final Color MAGENTA = Color.MAGENTA;
/**
* The color orange.
*/
public static final Color ORANGE = Color.ORANGE;
/**
* The color pink.
*/
public static final Color PINK = Color.PINK;
/**
* The color red.
*/
public static final Color RED = Color.RED;
/**
* The color white.
*/
public static final Color WHITE = Color.WHITE;
/**
* The color yellow.
*/
public static final Color YELLOW = Color.YELLOW;
/**
* Shade of blue used in <em>Introduction to Programming in Java</em>.
* It is Pantone 300U. The RGB values are approximately (9, 90, 166).
*/
public static final Color BOOK_BLUE = new Color(9, 90, 166);
/**
* Shade of light blue used in <em>Introduction to Programming in Java</em>.
* The RGB values are approximately (103, 198, 243).
*/
public static final Color BOOK_LIGHT_BLUE = new Color(103, 198, 243);
/**
* Shade of red used in <em>Algorithms, 4th edition</em>.
* It is Pantone 1805U. The RGB values are approximately (150, 35, 31).
*/
public static final Color BOOK_RED = new Color(150, 35, 31);
/**
* 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_CLEAR_COLOR = WHITE;
// current pen color
private static Color penColor;
// default canvas size is DEFAULT_SIZE-by-DEFAULT_SIZE
private static final int DEFAULT_SIZE = 512;
private static int width = DEFAULT_SIZE;
private static int height = DEFAULT_SIZE;
// default pen radius
private static final double DEFAULT_PEN_RADIUS = 0.002;
// current pen radius
private static double penRadius;
// show we draw immediately or wait until next show?
private static boolean defer = false;
// boundary of drawing canvas, 0% border
// private static final double BORDER = 0.05;
private static final double BORDER = 0.00;
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;
private static double xmin, ymin, xmax, ymax;
// for synchronization
private static Object mouseLock = new Object();
private static Object keyLock = new Object();
// default font
private static final Font DEFAULT_FONT = new Font("SansSerif", Font.PLAIN, 16);
// current font
private static Font font;
// double buffered graphics
private static BufferedImage offscreenImage, onscreenImage;
private static Graphics2D offscreen, onscreen;
// singleton for callbacks: avoids generation of extra .class files
private static StdDraw std = new StdDraw();
// the frame for drawing to the screen
private static JFrame frame;
// mouse state
private static boolean isMousePressed = false;
private static double mouseX = 0;
private static double mouseY = 0;
// queue of typed key characters
private static LinkedList<Character> keysTyped;
// set of key codes currently pressed down
private static TreeSet<Integer> keysDown;
// singleton pattern: client can't instantiate
private StdDraw() { }
// static initializer
static {
init();
}
/**
* Sets the canvas (drawing area) to be 512-by-512 pixels.
* This also erases the current drawing and resets the coordinate system,
* pen radius, pen color, and font back to their default values.
* Ordinarly, this method is called once, at the very beginning
* of a program.
*/
public static void setCanvasSize() {
setCanvasSize(DEFAULT_SIZE, DEFAULT_SIZE);
}
/**
* Sets the canvas (drawing area) to be <em>width</em>-by-<em>height</em> pixels.
* This also erases the current drawing and resets the coordinate system,
* pen radius, pen color, and font back to their default values.
* Ordinarly, 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 static void setCanvasSize(int canvasWidth, int canvasHeight) {
if (canvasWidth <= 0) throw new IllegalArgumentException("width must be positive");
if (canvasHeight <= 0) throw new IllegalArgumentException("height must be positive");
width = canvasWidth;
height = canvasHeight;
init();
}
// init
private static void init() {
if (frame != null) frame.setVisible(false);
frame = new JFrame();
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
setXscale();
setYscale();
offscreen.setColor(DEFAULT_CLEAR_COLOR);
offscreen.fillRect(0, 0, width, height);
setPenColor();
setPenRadius();
setFont();
clear();
// initialize keystroke buffers
keysTyped = new LinkedList<Character>();
keysDown = new TreeSet<Integer>();
// add antialiasing
RenderingHints hints = new RenderingHints(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
hints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
offscreen.addRenderingHints(hints);
// frame stuff
RetinaImageIcon icon = new RetinaImageIcon(onscreenImage);
JLabel draw = new JLabel(icon);
draw.addMouseListener(std);
draw.addMouseMotionListener(std);
frame.setContentPane(draw);
frame.addKeyListener(std); // 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("Standard Draw");
frame.setJMenuBar(createMenuBar());
frame.pack();
frame.requestFocusInWindow();
frame.setVisible(true);
}
// create the menu bar (changed to private)
private static JMenuBar createMenuBar() {
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("File");
menuBar.add(menu);
JMenuItem menuItem1 = new JMenuItem(" Save... ");
menuItem1.addActionListener(std);
// Java 10+: replace getMenuShortcutKeyMask() with getMenuShortcutKeyMaskEx()
menuItem1.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_S,
Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
menu.add(menuItem1);
return menuBar;
}
/***************************************************************************
* User and screen coordinate systems.
***************************************************************************/
// 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");
}
/**
* Sets the <em>x</em>-scale to be the default (between 0.0 and 1.0).
*/
public static void setXscale() {
setXscale(DEFAULT_XMIN, DEFAULT_XMAX);
}
/**
* Sets the <em>y</em>-scale to be the default (between 0.0 and 1.0).
*/
public static void setYscale() {
setYscale(DEFAULT_YMIN, DEFAULT_YMAX);
}
/**
* Sets the <em>x</em>-scale and <em>y</em>-scale to be the default
* (between 0.0 and 1.0).
*/
public static void setScale() {
setXscale();
setYscale();
}
/**
* Sets the <em>x</em>-scale to the specified range.
*
* @param min the minimum value of the <em>x</em>-scale
* @param max the maximum value of the <em>x</em>-scale
* @throws IllegalArgumentException if {@code (max == min)}
* @throws IllegalArgumentException if either {@code min} or {@code max} is either NaN or infinite
*/
public static 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");
synchronized (mouseLock) {
xmin = min - BORDER * size;
xmax = max + BORDER * size;
}
}
/**
* Sets the <em>y</em>-scale to the specified range.
*
* @param min the minimum value of the <em>y</em>-scale
* @param max the maximum value of the <em>y</em>-scale
* @throws IllegalArgumentException if {@code (max == min)}
* @throws IllegalArgumentException if either {@code min} or {@code max} is either NaN or infinite
*/
public static 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");
synchronized (mouseLock) {
ymin = min - BORDER * size;
ymax = max + BORDER * size;
}
}
/**
* Sets both the <em>x</em>-scale and <em>y</em>-scale to the (same) specified range.
*
* @param min the minimum value of the <em>x</em>- and <em>y</em>-scales
* @param max the maximum value of the <em>x</em>- and <em>y</em>-scales
* @throws IllegalArgumentException if {@code (max == min)}
* @throws IllegalArgumentException if either {@code min} or {@code max} is either NaN or infinite
*/
public static void setScale(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");
synchronized (mouseLock) {
xmin = min - BORDER * size;
xmax = max + BORDER * size;
ymin = min - BORDER * size;
ymax = max + BORDER * size;
}
}
// helper functions that scale from user coordinates to screen coordinates and back
private static double scaleX(double x) { return width * (x - xmin) / (xmax - xmin); }
private static double scaleY(double y) { return height * (ymax - y) / (ymax - ymin); }
private static double factorX(double w) { return w * width / Math.abs(xmax - xmin); }
private static double factorY(double h) { return h * height / Math.abs(ymax - ymin); }
private static double userX(double x) { return xmin + x * (xmax - xmin) / width; }
private static double userY(double y) { return ymax - y * (ymax - ymin) / height; }
/**
* Clears the screen to the default color (white).
*/
public static void clear() {
clear(DEFAULT_CLEAR_COLOR);
}
/**
* Clears the screen to the specified color.
*
* @param color the color to make the background
* @throws IllegalArgumentException if {@code color} is {@code null}
*/
public static void clear(Color color) {
validateNotNull(color, "color");
offscreen.setColor(color);
offscreen.fillRect(0, 0, width, height);
offscreen.setColor(penColor);
draw();
}
/**
* Returns the current pen radius.
*
* @return the current value of the pen radius
*/
public static double getPenRadius() {
return penRadius;
}
/**
* Sets the pen size to the default size (0.002).
* The pen is circular, so that lines have rounded ends, and when you set the
* pen radius and draw a point, you get a circle of the specified radius.
* The pen radius is not affected by coordinate scaling.
*/
public static void setPenRadius() {
setPenRadius(DEFAULT_PEN_RADIUS);
}
/**
* Sets the radius of the pen to the specified size.
* The pen is circular, so that lines have rounded ends, and when you set the
* pen radius and draw a point, you get a circle of the specified radius.
* The pen radius is not affected by coordinate scaling.
*
* @param radius the radius of the pen
* @throws IllegalArgumentException if {@code radius} is negative, NaN, or infinite
*/
public static void setPenRadius(double radius) {
validate(radius, "pen radius");
validateNonnegative(radius, "pen radius");
penRadius = radius;
float scaledPenRadius = (float) (radius * DEFAULT_SIZE);
BasicStroke stroke = new BasicStroke(scaledPenRadius, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND);
// BasicStroke stroke = new BasicStroke(scaledPenRadius);
offscreen.setStroke(stroke);
}
/**
* Returns the current pen color.
*
* @return the current pen color
*/
public static Color getPenColor() {
return penColor;
}
/**
* Sets the pen color to the default color (black).
*/
public static void setPenColor() {
setPenColor(DEFAULT_PEN_COLOR);
}
/**
* Sets the pen color to the specified color.
* <p>
* The predefined pen colors are
* {@code StdDraw.BLACK}, {@code StdDraw.BLUE}, {@code StdDraw.CYAN},
* {@code StdDraw.DARK_GRAY}, {@code StdDraw.GRAY}, {@code StdDraw.GREEN},
* {@code StdDraw.LIGHT_GRAY}, {@code StdDraw.MAGENTA}, {@code StdDraw.ORANGE},
* {@code StdDraw.PINK}, {@code StdDraw.RED}, {@code StdDraw.WHITE}, and
* {@code StdDraw.YELLOW}.
*
* @param color the color to make the pen
* @throws IllegalArgumentException if {@code color} is {@code null}
*/
public static void setPenColor(Color color) {
validateNotNull(color, "color");
penColor = color;
offscreen.setColor(penColor);
}
/**
* Sets the pen color to the specified 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 static 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));
}
/**
* Returns the current font.
*
* @return the current font
*/
public static Font getFont() {
return font;
}
/**
* Sets the font to the default font (sans serif, 16 point).
*/
public static void setFont() {
setFont(DEFAULT_FONT);
}
/**
* Sets the font to the specified value.
*
* @param font the font
* @throws IllegalArgumentException if {@code font} is {@code null}
*/
public static void setFont(Font font) {
validateNotNull(font, "font");
StdDraw.font = font;
}
/***************************************************************************
* Drawing geometric shapes.
***************************************************************************/
/**
* Draws a line segment between (<em>x</em><sub>0</sub>, <em>y</em><sub>0</sub>) and
* (<em>x</em><sub>1</sub>, <em>y</em><sub>1</sub>).
*
* @param x0 the <em>x</em>-coordinate of one endpoint
* @param y0 the <em>y</em>-coordinate of one endpoint
* @param x1 the <em>x</em>-coordinate of the other endpoint