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How can I produce 5 x 7 dot matrix type digits for a clock project?
Here's an example of what I'm looking for.
I manually coded the position of each dot in each digit.
Is there a better way to create dot matrix digits?
By better I mean easier to code, easier to verify, makes use of existing fonts or other components, or anything else an experienced Swing developer might consider as an important consideration.
The rest of this question is the context for the naysayers that claim I didn't put enough effort into formulating my question.
Since I'm providing an answer to this question, I'm not posting fake bad code in the question. Sure, we appreciate it when people show their efforts. The code and text in my answer should supplement the question, in my opinion.
A few days ago, as I'm writing this, someone posted a question about making a clock with dot-matrix digits. The person posting the question provided code and a picture of what they had created. The person had created a BufferedImage where they had hardcoded the position of each square dot in his 4 x 7 dot matrix digits.
I was impressed with how much work the person had put into his BufferedImage, so I went off to my Eclipse to figure out how to generalize what he had done.
While I was away, people commented and closed his question. By the time I got back with my answer, the person had deleted his question.
Since I had what I thought was a good answer, I searched for an appropriate question. When I didn't find an appropriate question, I created a question.
Sure, I focused more on my answer than my question. Silly me, I thought that the answer would help provide context for the question.
Well, I hope that this explanation sheds some more light on why I thought this topic was important enough to create a question and ask for answers.
Unfortunately, you have to code the position of each dot in each digit.
However, you can do this in a flexible way.
Here's what I mean. A 5 x 7 dot matrix digit can be represented as a two-dimensional int array. It could also be represented as a boolean array, but a matrix of 0 and 1 values is easier to visually verify.
As an example. here's a method to code the zero digit. You can see that the ones create a visual outline that can be easily verified.
private int[][] defineZeroMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 1, 0, 0, 0, 1 };
matrix[3] = new int[] { 1, 0, 0, 0, 1 };
matrix[4] = new int[] { 1, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
It took me about 15 minutes to code all of the dot matrix digit matrices.
It's possible to code a dot matrix digit using a sparse matrix. Unfortunately, that idea leads to more code that's visually harder to verify.
Here's an example of the dot matrix digit two coded as a sparse matrix of coordinates.
private Point[] defineTwoCoordinates() {
Point[] array = new Point[14];
array[0] = new Point(0, 1);
array[1] = new Point(1, 0);
array[2] = new Point(2, 0);
array[3] = new Point(3, 0);
array[4] = new Point(4, 1);
array[5] = new Point(4, 2);
array[6] = new Point(3, 3);
array[7] = new Point(2, 4);
array[8] = new Point(1, 5);
array[9] = new Point(0, 6);
array[10] = new Point(1, 6);
array[11] = new Point(2, 6);
array[12] = new Point(3, 6);
array[13] = new Point(4, 6);
return array;
}
After we've coded all of the digit matrices, we'll create an array of matrices.
private int[][][] matrices;
The leftmost index is the digit, from 0 to 9. The second index is the row of the digit matrix. The third index is the column of the digit matrix.
Finally, we extend a JPanel and override the paintComponent method to actually paint the dot matrix digit.
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(dotColor);
for (int row = 0; row < matrices[digit].length; row++) {
for (int column = 0; column < matrices[digit][row].length; column++) {
if (matrices[digit][row][column] != 0) {
int x = margin + column * pixelWidth;
int y = margin + row * pixelWidth;
g.fillOval(x, y, dotWidth, dotWidth);
}
}
}
}
Here's a complete runnable example of how you would create a dot matrix digit panel by extending a JPanel, and use several dot matrix digit panels to create whatever GUI you want.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class DotMatrixDigits implements Runnable {
public static void main(String[] args) {
SwingUtilities.invokeLater(new DotMatrixDigits());
}
#Override
public void run() {
JFrame frame = new JFrame("Dot Matrix Digits");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(defineTopPanel(), BorderLayout.BEFORE_FIRST_LINE);
frame.add(defineBottomPanel(), BorderLayout.AFTER_LAST_LINE);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
private JPanel defineTopPanel() {
JPanel panel = new JPanel();
panel.add(new DotMatrixDigit(0, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(1, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(2, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(3, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(4, Color.YELLOW, Color.BLACK));
return panel;
}
private JPanel defineBottomPanel() {
JPanel panel = new JPanel();
panel.add(new DotMatrixDigit(5, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(6, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(7, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(8, Color.YELLOW, Color.BLACK));
panel.add(new DotMatrixDigit(9, Color.YELLOW, Color.BLACK));
return panel;
}
/**
* <p>
* The <code>DotMatrixDigit</code> class creates a dot-matrix digit panel by
* extending <code>JPanel</code>. The dot matrix digit is 5 positions across and
* 7 positions down. The size of the dot and distance between dots are defined
* in the constructor of this class. The shape of the dot is determined in the
* <code>paintComponent</code> method.
* </p>
*
* #author Gilbert G. Le Blanc
* #version 1.8 - 20 October 2020
*
* #see JPanel
* #see Color
*/
public class DotMatrixDigit extends JPanel {
private static final long serialVersionUID = 1L;
/** int field to hold the digit to display **/
private int digit;
/** int field to hold the width of the dot in pixels **/
private int dotWidth;
/** int field to hold the distance between the
* top left corner of the dots in pixels **/
private int pixelWidth;
/** int field to hold the margin size in
* pixels surrounding the digit **/
private int margin;
private final Color dotColor;
private int[][][] matrices;
/**
* <p>
* This constructor creates a dot matrix digit panel. The preferred size of the
* panel is determined by the pixel width of each dot, including the space
* between the dots.
* </p>
*
* #param digit - The initial digit to display from 0 through 9.
* #param dotColor - The <code>Color</code> of the dots.
* #param backgroundColor - The background <code>Color</code> of the dot matrix
* digit panel.
*
*/
public DotMatrixDigit(int digit, Color dotColor, Color backgroundColor) {
this.digit = digit;
this.dotColor = dotColor;
this.dotWidth = 10;
this.pixelWidth = 15;
this.margin = dotWidth;
this.matrices = defineDigitMatricies();
int width = 4 * pixelWidth + dotWidth + margin + margin;
int height = 6 * pixelWidth + dotWidth + margin + margin;
this.setBackground(backgroundColor);
this.setPreferredSize(new Dimension(width, height));
}
private int[][][] defineDigitMatricies() {
int[][][] matrices = new int[10][][];
matrices[0] = defineZeroMatrix();
matrices[1] = defineOneMatrix();
matrices[2] = defineTwoMatrix();
matrices[3] = defineThreeMatrix();
matrices[4] = defineFourMatrix();
matrices[5] = defineFiveMatrix();
matrices[6] = defineSixMatrix();
matrices[7] = defineSevenMatrix();
matrices[8] = defineEightMatrix();
matrices[9] = defineNineMatrix();
return matrices;
}
private int[][] defineZeroMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 1, 0, 0, 0, 1 };
matrix[3] = new int[] { 1, 0, 0, 0, 1 };
matrix[4] = new int[] { 1, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
private int[][] defineOneMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 0, 1, 0, 0 };
matrix[1] = new int[] { 0, 1, 1, 0, 0 };
matrix[2] = new int[] { 1, 0, 1, 0, 0 };
matrix[3] = new int[] { 0, 0, 1, 0, 0 };
matrix[4] = new int[] { 0, 0, 1, 0, 0 };
matrix[5] = new int[] { 0, 0, 1, 0, 0 };
matrix[6] = new int[] { 1, 1, 1, 1, 1 };
return matrix;
}
private int[][] defineTwoMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 0, 0, 0, 0, 1 };
matrix[3] = new int[] { 0, 0, 0, 1, 0 };
matrix[4] = new int[] { 0, 0, 1, 0, 0 };
matrix[5] = new int[] { 0, 1, 0, 0, 0 };
matrix[6] = new int[] { 1, 1, 1, 1, 1 };
return matrix;
}
private int[][] defineThreeMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 0, 0, 0, 0, 1 };
matrix[3] = new int[] { 0, 0, 1, 1, 0 };
matrix[4] = new int[] { 0, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
private int[][] defineFourMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 0, 0, 1, 0 };
matrix[1] = new int[] { 0, 0, 1, 1, 0 };
matrix[2] = new int[] { 0, 1, 0, 1, 0 };
matrix[3] = new int[] { 1, 0, 0, 1, 0 };
matrix[4] = new int[] { 1, 1, 1, 1, 1 };
matrix[5] = new int[] { 0, 0, 0, 1, 0 };
matrix[6] = new int[] { 0, 0, 0, 1, 0 };
return matrix;
}
private int[][] defineFiveMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 1, 1, 1, 1, 1 };
matrix[1] = new int[] { 1, 0, 0, 0, 0 };
matrix[2] = new int[] { 1, 0, 0, 0, 0 };
matrix[3] = new int[] { 1, 1, 1, 1, 0 };
matrix[4] = new int[] { 0, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
private int[][] defineSixMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 1, 0, 0, 0, 0 };
matrix[3] = new int[] { 1, 1, 1, 1, 0 };
matrix[4] = new int[] { 1, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
private int[][] defineSevenMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 1, 1, 1, 1, 1 };
matrix[1] = new int[] { 0, 0, 0, 0, 1 };
matrix[2] = new int[] { 0, 0, 0, 0, 1 };
matrix[3] = new int[] { 0, 0, 0, 1, 0 };
matrix[4] = new int[] { 0, 0, 1, 0, 0 };
matrix[5] = new int[] { 0, 0, 1, 0, 0 };
matrix[6] = new int[] { 0, 0, 1, 0, 0 };
return matrix;
}
private int[][] defineEightMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 1, 0, 0, 0, 1 };
matrix[3] = new int[] { 0, 1, 1, 1, 0 };
matrix[4] = new int[] { 1, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
private int[][] defineNineMatrix() {
int[][] matrix = new int[7][];
matrix[0] = new int[] { 0, 1, 1, 1, 0 };
matrix[1] = new int[] { 1, 0, 0, 0, 1 };
matrix[2] = new int[] { 1, 0, 0, 0, 1 };
matrix[3] = new int[] { 0, 1, 1, 1, 1 };
matrix[4] = new int[] { 0, 0, 0, 0, 1 };
matrix[5] = new int[] { 1, 0, 0, 0, 1 };
matrix[6] = new int[] { 0, 1, 1, 1, 0 };
return matrix;
}
/**
* <p>
* The <code>setDigit</code> method sets the digit to display and repaints the
* panel.
* </p>
*
* #param digit - A digit from 0 through 9.
*/
public void setDigit(int digit) {
this.digit = digit;
this.repaint();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(dotColor);
for (int row = 0; row < matrices[digit].length; row++) {
for (int column = 0; column < matrices[digit][row].length; column++) {
if (matrices[digit][row][column] != 0) {
int x = margin + column * pixelWidth;
int y = margin + row * pixelWidth;
g.fillOval(x, y, dotWidth, dotWidth);
}
}
}
}
}
}
Is there a better way to create dot matrix digits?
Don't know if 'better' (depends on whether effort or accuracy is the primary consideration) but there is a way to calculate the array based on the Shape of the digit.
Here is the result for a (bold) version of the default Monospaced font on this machine.
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.font.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
public class FontToDotMatrix {
private JComponent ui = null;
Shape[] shapes = new Shape[10];
JComboBox fonts;
PixelArray[] pixelArrays = new PixelArray[10];
FontToDotMatrix() {
initUI();
}
public final void initUI() {
if (ui != null) {
return;
}
ui = new JPanel(new BorderLayout(4, 4));
ui.setBorder(new EmptyBorder(4, 4, 4, 4));
String[] fontFamilies = GraphicsEnvironment.
getLocalGraphicsEnvironment().getAvailableFontFamilyNames();
fonts = new JComboBox(fontFamilies);
ui.add(fonts, BorderLayout.PAGE_START);
JPanel digitPanel = new JPanel(new GridLayout(2, 5, 4, 4));
ui.add(digitPanel);
digitPanel.setBackground(Color.RED);
for (int ii = 0; ii < 10; ii++) {
PixelArray pixelArray = new PixelArray();
pixelArrays[ii] = pixelArray;
digitPanel.add(pixelArray);
}
ActionListener listener = (ActionEvent e) -> {
for (int ii = 0; ii < 10; ii++) {
pixelArrays[ii].updatePixels(getLitPixels("" + ii));
}
};
fonts.addActionListener(listener);
fonts.setSelectedItem("Monospaced");
}
private Shape moveShapeToCenter(Shape shape) {
int w = 50;
int h = 70;
Rectangle2D b = shape.getBounds2D();
double xOff = -b.getX() + ((w - b.getWidth()) / 2d);
double yOff = -b.getY() + ((h - b.getHeight()) / 2d);
AffineTransform move = AffineTransform.getTranslateInstance(xOff, yOff);
return move.createTransformedShape(shape);
}
private boolean[][] getLitPixels(String digit) {
Font font = new Font(fonts.getSelectedItem().toString(), Font.BOLD, 70);
Shape shape = getShapeOfCharacter(font, digit);
Rectangle2D rect = shape.getBounds2D();
double h = rect.getHeight();
double ratio = 70d / h;
AffineTransform scale = AffineTransform.getScaleInstance(ratio, ratio);
shape = moveShapeToCenter(scale.createTransformedShape(shape));
boolean[][] bools = new boolean[5][7];
for (int yy = 0; yy < 7; yy++) {
for (int xx = 0; xx < 5; xx++) {
Point point = new Point((xx * 10) + 5, (yy * 10) + 5);
bools[xx][yy] = shape.contains(point);
}
}
return bools;
}
public JComponent getUI() {
return ui;
}
private Shape getShapeOfCharacter(Font font, String digit) {
BufferedImage bi = new BufferedImage(
1, 1, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bi.createGraphics();
FontRenderContext frc = g.getFontRenderContext();
GlyphVector gv = font.createGlyphVector(frc, digit);
return gv.getOutline();
}
public static void main(String[] args) {
Runnable r = () -> {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception useDefault) {
}
FontToDotMatrix o = new FontToDotMatrix();
JFrame f = new JFrame(o.getClass().getSimpleName());
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(o.getUI());
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
};
SwingUtilities.invokeLater(r);
}
}
class PixelArray extends JPanel {
JLabel[][] labels = new JLabel[5][7];
PixelArray() {
setLayout(new GridLayout(7, 5));
BufferedImage bi = new BufferedImage(10, 10, BufferedImage.TYPE_INT_ARGB);
ImageIcon icon = new ImageIcon(bi);
for (int yy = 0; yy < labels[0].length; yy++) {
for (int xx = 0; xx < labels.length; xx++) {
JLabel l = new JLabel(icon);
labels[xx][yy] = l;
l.setOpaque(true);
add(l);
}
}
}
public void updatePixels(boolean[][] bools) {
for (int xx = 0; xx < labels.length; xx++) {
for (int yy = 0; yy < labels[0].length; yy++) {
JLabel l = labels[xx][yy];
if (bools[xx][yy]) {
l.setBackground(Color.WHITE);
} else {
l.setBackground(Color.BLACK);
}
}
}
}
}
Related
I'm building a program that can recognise images from the air.
I am able to load the image and convert it to black and white, but I'm having trouble attempting to get the pixel values into an array so that I can use a union find to link clusters of white pixels and black pixels.
Here is what I have so far:
import javafx.stage.FileChooser;
import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
public class Image {
public static void main(String args[])
{
new Image();
}
public Image()
{
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
JFrame frame = new JFrame("Image");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //closes application properly
frame.add(new ImagePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ImagePane extends JPanel {
private BufferedImage image;
private BufferedImage bwImage;
public ImagePane() {
try {
FileChooser fileChooser = new FileChooser();
image = ImageIO.read(new File("C:/Users/Connor/Desktop/image.jpg"));
this.image = image;
bwImage = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_BYTE_BINARY);
this.bwImage = bwImage;
Graphics2D g2d = bwImage.createGraphics();
g2d.drawImage(image, 0, 0, this);
g2d.dispose();
} catch (IOException ex) {
ex.printStackTrace();
}
}
public Dimension getPreferredSize() {
Dimension size = super.getPreferredSize();
if (image != null) {
size = new Dimension(image.getWidth() * 2, image.getHeight());
}
return size;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (image != null) {
int x = (getWidth() - (image.getWidth() * 2)) / 2;
int y = (getHeight() - (image.getHeight()));
g.drawImage(image, x, y, this);
x += image.getWidth();
g.drawImage(bwImage, x, y, this);
}
}
}
}
I'm hoping to get some output like the following:
{ 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1 },
{ 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0 },
{ 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0 },
{ 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1 },
{ 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0 },
{ 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0 },
{ 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0 }
So a way to do this would be using a BitSet.
A small code example how to go about this:
//img is your black and white image of type BufferedImage
// Get the width and height of your image
int width = img.getWidth();
int height = img.getHeight();
// create a BitSet of the correct size
BitSet bits = new BitSet(width * height);
// Iterate through your image's pixels and set the correct bits.
for (int y = 0; y < height; ++y)
{
for (int x = 0; x < width; ++x)
{
// Check against 0xffffffff which is the RGB value of white.
if (img.getRGB(x, y) == 0xffffffff)
{
bits.set(y * width + x);
}
}
}
After this you have a BitSet with a set bit representing the color white and an unset bit representing the color black. You can now do mathematical analysis on that as you please.
I need to find the best fitting regression line for a set of points.
For example for this matrix:
int b [][] = { { 3, 1, 0, 0, 0, 0, 0, 0, 0 },
{ 1, 2, 3, 1, 0, 1, 0, 0, 0 },
{ 0, 1, 2, 1, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 3, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 1, 3, 0, 0 },
{ 0, 0, 0, 0, 0, 1, 2, 3, 1 },
{ 0, 0, 0, 0, 0, 1, 1, 1, 2 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 1 } };
Every number represents the amount of data points (weight I suppose) at that location (where rows are the X axis and Columns are for the Y).
I have attempted to use the SimpleRegression class from the apache mathematics library and am having some issues.
First, it doesn't appear to support weights. Second I believe that I'm doing something wrong, even for a matrix that is nothing but 1's on the main diagonal the slope/intercept results make no sense.
public static void main(String[] args) {
double a[][] = new double[9][9];
for (int i = 0; i < 9; i++)
a[i][i] = 1;
SimpleRegression r = new SimpleRegression(true);
r.addData(a);
System.out.println("Slope = " + r.getSlope());
System.out.println("Intercept = " + r.getIntercept());
}
This gives me results that are incorrect. I would assume that this matrix represents the function f(x) = x yet the slope I'm getting is -0.12499..
Could anyone point me at what I'm doing wrong?
I have a feeling I'm not only misusing the code but also the mathematics.
As the comments say, addData() expects a 2xN matrix of x y positions or individual x y positions. The following example returns a slope of 1 for a diagonal matrix as expected:
public static void main(String[] args) {
double a[][] = new double[9][9];
for (int i = 0; i < 9; i++)
a[i][i] = 1;
SimpleRegression r = new SimpleRegression(true);
addData(r, a);
System.out.println("Slope = " + r.getSlope());
System.out.println("Intercept = " + r.getIntercept());
}
public static void addData(SimpleRegression r, double[][] data) {
for(int x=0; x<data.length; x++) {
for(int y=0; y<data[0].length; y++) {
for(int i=0; i<data[x][y]; i++) {
r.addData(x, y);
}
}
}
}
The example assumes that index 0 corresponds to a position of 0, index 1 corresponds to a position of 1 and so on. If this is not the case you need to add a function to transform index to position.
I have a new problem with the repaint methode.
There is a frame in which I paint several graphics together. When I click in a specific range of coordinates, it should change the status of one graphic and then repaint this specific range. But this repaint doesn't work...
This is the method that initialize the graphics (the declaration of the graphics isn't shown):
private void initComponents() {
Painter painter = new Painter();
setExtendedState(MAXIMIZED_BOTH);
int width = (int) getContentPane().getBounds().getWidth();
int height = (int) getContentPane().getBounds().getHeight();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
g0 = new Gleis(25, 1, 4, 0, 0);
g1 = new Gleis(26, 1, 0, 1, 0);
k0 = new KnopfRot(26, 1, 0, false);
g2 = new Gleis(27, 1, 0, 2, 0);
g3 = new Gleis(28, 1, 0, 3, 0);
g4 = new Gleis(29, 1, 0, 4, 0);
g5 = new Gleis(30, 1, 0, 5, 0);
g6 = new Gleis(31, 1, 0, 6, 0);
g7 = new Gleis(32, 1, 0, 7, 0);
g8 = new Gleis(33, 1, 0, 8, 0);
g9 = new Gleis(34, 1, 0, 9, 0);
g10 = new Gleis(35, 1, 0, 10, 0);
g11 = new Gleis(36, 1, 0, 11, 0);
g12 = new Gleis(37, 1, 0, 12, 0);
g13 = new Gleis(38, 1, 0, 13, 0);
k1 = new KnopfRot(38, 1, 1, false);
painter.addGleis(g0);
painter.addGleis(g1);
painter.addKnopfRot(k0);
painter.addGleis(g2);
painter.addGleis(g3);
painter.addGleis(g4);
painter.addGleis(g5);
painter.addGleis(g6);
painter.addGleis(g7);
painter.addGleis(g8);
painter.addGleis(g9);
painter.addGleis(g10);
painter.addGleis(g11);
painter.addGleis(g12);
painter.addGleis(g13);
painter.addKnopfRot(k1);
this.addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent e) {
double x = e.getX();
double y = e.getY();
frameMouseClicked(x, y);
}
});
this.getContentPane().add(painter);
this.setVisible(true);
}
public void frameMouseClicked(double x, double y) {
if(x >= 306 && x <= 314 && y >= 55 && y <= 63){ //x+11 y+32
Painter painter = new Painter();
painter.updateKnopfRot(k0, 26, 1, 306, 55);
repaint();
}
else{}
}
Then my class KnopfRot:
public class KnopfRot {
int xposition;
int yposition;
int type;
int id;
boolean status;
//Konstruktor
public KnopfRot(int xpos, int ypos, int id, boolean status){
this.xposition = xpos * 11 + 12;
this.yposition = ypos * 11 + 12;
this.id = id; //zur eindeutigen Bezeichnung der Gleiselemente
this.status = status;
}
public void draw(Graphics2D g) {
if (!status) {
Ellipse2D.Double aussen = new Ellipse2D.Double(xposition, yposition, 8, 8);
Ellipse2D.Double innen = new Ellipse2D.Double(xposition + 1, yposition + 1, 6, 6);
g.setColor(Color.black);
g.fill(aussen);
g.setColor(Color.red);
g.fill(innen);
}
else if (status){
Ellipse2D.Double aussen = new Ellipse2D.Double(xposition, yposition, 7, 7);
Ellipse2D.Double innen = new Ellipse2D.Double(xposition + 1, yposition + 1, 5, 5);
g.setColor(Color.black);
g.fill(aussen);
g.setColor(Color.red);
g.fill(innen);
}
else {}
}
}
And the Painter-Class with the method updateKnopfRot which is callen in the MouseEvent:
public class Painter extends JPanel {
private List<Gleis> gleisList = new ArrayList<>();
private List<KnopfRot> knopfList = new ArrayList<>();
//fügt ein neues Element der Liste gleisList hinzu
public void addGleis(Gleis gleis) {
gleisList.add(gleis);
}
public void addKnopfRot(KnopfRot knopf) {
knopfList.add(knopf);
}
public void updateKnopfRot(KnopfRot knopf, int x, int y, int xpos, int ypos) {
knopfList.remove(knopf);
addKnopfRot(new KnopfRot(x, y, 0, true));
}
//paint-Methode geht jedes Element der Liste gleisList durch und führt die draw-Methode in Gleis.java aus
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
for (Gleis gleis : gleisList) {
gleis.draw(g2);
}
for (KnopfRot knopf : knopfList) {
knopf.draw(g2);
}
}
}
Sorry for so much code but I can't reduce it to explain/show the problem.
Can somebody help?
You're creating a new Painter(...) object within your frameMouseClicked(...) method, and then changing the state of this object, but this will have no effect on the completely different visualized Painter object. Your solution -- don't create a new Painter object, but rather use a reference to the original, and then try to change its state.
Regarding:
Sorry for so much code but I can't reduce it to explain/show the problem.
If this answer doesn't solve your problem, then yes, you can reduce this code and make it runnable as we've discussed in the past. Yes it will take some effort on your part to create and post a valid MCVE, but it's worth it.
How to add multiple finish line in traverse? example the player needs to go to the 1st finish line, then to next, then up to the last. this is the code. i want to have 1 up to 4 traversing point. this is the code. i dunno where to put the statement.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class MazeSearchGUI extends JPanel implements ActionListener, Runnable {
private static final long serialVersionUID = 1L;
private final int WALL = 0; // A wall position value
private final int EMPTY = 1; // An empty position value
private final int TRIED = 3; // Previously tried path value
private final int PATH = 7; // Successful path value
private final int HEADERSZ = 60; // Height in header area
private int width, height; // Width and Height
private Image brick; // Brick images for walls
private Image flag; // Flag finish line images
private Image mole; // Flag finish line images
private int brickWidth, brickHeight; // Brick dimensions
private int flagWidth, flagHeight; // Flag image dimensions
private int moleWidth, moleHeight; // Flag image dimensions
private Color backCol = Color.white; // Header background color
private Color mazeCol = Color.yellow; // Maze background color
private Color triedCol = Color.lightGray; // Tried path color
private Color successCol = Color.green; // Successful path color
private Timer timer; // Timer to start game
private int startDelay = 3000; // Delay to start traversal
private int stepDelay = 1000; // Delay between each step
private static JPanel mainPanel; // Main game panel
private static String headLabel; // String at top
private static boolean success = false; // Flags successful path
private static int xPos, yPos; // Current position
// Data structure of Grid
private static int[][] grid = { { 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1 },
{ 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1 },
{ 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0 },
{ 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1 },
{ 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1 },
{ 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1 },
{ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 } };
// No Arg Constructor - the thread process runs this
public MazeSearchGUI() {
}
// One Arg Constructor - main panel process runs this
public MazeSearchGUI(String label) {
headLabel = label;
backCol = new Color(255, 182, 193);
xPos = 0;
yPos = 0;
brick = new ImageIcon("brick.png").getImage();
flag = new ImageIcon("flag.png").getImage();
mole = new ImageIcon("mole.png").getImage();
MediaTracker track = new MediaTracker(this);
track.addImage(brick, 0);
track.addImage(flag, 0);
track.addImage(mole, 0);
try {
track.waitForAll();
} catch (InterruptedException e) {
}
brickWidth = brick.getWidth(null);
brickHeight = brick.getHeight(null);
flagWidth = flag.getWidth(null);
flagHeight = flag.getHeight(null);
moleWidth = mole.getWidth(null);
moleHeight = mole.getHeight(null);
width = brickWidth * grid[0].length;
height = brickHeight * grid.length + HEADERSZ;
setBackground(backCol);
setPreferredSize(new Dimension(width, height));
setFocusable(true);
timer = new Timer(startDelay, this);
timer.start();
}
// runs once just to start the traversal thread
public void actionPerformed(ActionEvent event) {
timer.stop();
(new Thread(new MazeSearchGUI())).start();
}
// starts the traversal thread
public void run() {
if (traverse(0, 0)) {
success = true;
headLabel = "I Found A Way Out!";
mainPanel.repaint();
// JOptionPane.showMessageDialog(null,"A successful path was found!");
} else {
headLabel = "There's No Way Out!";
mainPanel.repaint();
// JOptionPane.showMessageDialog(null,"There is no way out of this maze!");
}
}
// Updates the window
public void paintComponent(Graphics page) {
super.paintComponent(page);
page.setColor(backCol);
page.fillRect(0, 0, width, HEADERSZ);
page.setColor(mazeCol);
page.fillRect(0, HEADERSZ, width, height - HEADERSZ);
page.setColor(Color.black);
page.setFont(new Font("Arial", Font.BOLD, 24));
FontMetrics metrics = page.getFontMetrics();
int labelWidth = metrics.stringWidth(headLabel);
page.drawString(headLabel, (width - labelWidth) / 2, HEADERSZ - 20);
page.drawImage(flag, grid[0].length * brickWidth
- (brickWidth + flagWidth) / 2, height
- (brickHeight + flagHeight) / 2, null);
for (int row = 0; row < grid.length; ++row) {
for (int col = 0; col < grid[row].length; ++col) {
if (grid[row][col] == WALL)
page.drawImage(brick, col * brickWidth, row * brickHeight
+ HEADERSZ, null);
else if (success) {
if (grid[row][col] == PATH) {
page.setColor(successCol);
page.fillRect(col * brickWidth, row * brickHeight
+ HEADERSZ, brickWidth, brickHeight);
}
} else if (grid[row][col] == TRIED
&& (row != yPos || col != xPos)) {
page.setColor(triedCol);
page.fillRect(col * brickWidth, row * brickHeight
+ HEADERSZ, brickWidth, brickHeight);
}
}
}
page.drawImage(mole, (xPos + 1) * brickWidth - (brickWidth + moleWidth)
/ 2, HEADERSZ + (yPos + 1) * brickHeight
- (brickHeight + moleHeight) / 2, null);
}
// Attempts to recursively traverse the maze. Inserts special
// characters indicating locations that have been tried and that
// eventually become part of the solution.
public boolean traverse(int row, int col) {
boolean done = false;
if (valid(row, col)) {
pause(stepDelay); // half second waits
xPos = col;
yPos = row;
grid[row][col] = TRIED; // this cell has been tried
mainPanel.repaint();
if (row == grid.length - 1 && col == grid[0].length - 1)
done = true; // the maze is solved
else {
done = traverse(row + 1, col); // down
if (!done)
done = traverse(row, col + 1); // right
if (!done)
done = traverse(row - 1, col); // up
if (!done)
done = traverse(row, col - 1); // left
}
if (done) // this location is part of the final path
grid[row][col] = PATH;
}
return done;
}
// Determines if a specific location is valid.
private boolean valid(int row, int col) {
// check if cell is in the bounds of the matrix
if (row >= 0 && row < grid.length && col >= 0 && col < grid[row].length)
// check if cell is not blocked and not previously tried
if (grid[row][col] == EMPTY)
return true;
return false;
}
public void pause(long millisecs) {
try {
Thread.sleep(millisecs);
} catch (InterruptedException e) {
}
}
public static void main(String[] args) {
JFrame frame = new JFrame("Maze Search GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainPanel = new MazeSearchGUI("Trying To Traverse This Maze...");
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setVisible(true);
}
}
Your code seems pretty procedural (meaning you have lots of code in a single class, without having different objects with state and behaviour). Applying changes will be very difficult and complex. Try to write object oriented code with different classes, each having their own state and responsibility.
This way you could have one class for the character sprite, one for the grid, one for the traversing points. If you want the points to have a certain order in which they need to be visited, an option would be to implement the state pattern.
Have a look at this https://en.wikipedia.org/wiki/State_pattern
and this http://gameprogrammingpatterns.com/state.html for the state pattern.
For more specific answers, please reduce your code example to the minimum needed to understand your question, and provide more information about the game itself.
I am developing a steganography program for a computer programming class. It appears to gives random ascii symbols. The output is supposed to be BINARY. The encode message method was given to us by my teacher. We just have to program the decode part.
import java.awt.*;
class HideMessage {
public void encodeMessage(Picture stegoObject, int[] binaryArray) {
Pixel pixelTarget = new Pixel(stegoObject, 0, 0);
Pixel[] pixelArray = stegoObject.getPixels();
Color pixelColor = null;
int redValue = 0;
for (int x = 0; x < binaryArray.length; x++) {
redValue = binaryArray[x];
pixelTarget = pixelArray[x];
pixelTarget.setRed(redValue);
}
pixelTarget = pixelArray[binaryArray.length];
pixelTarget.setRed(255);
System.out.println("FinishedPic");
stegoObject.write("SecretMessage.bmp");
stegoObject.explore();
}
public void decodeMessage(Picture decodepic) {
int redValue = 0;
Pixel targetPixel = null;
Color pixelColor = null;
int sum = 0;
for (int x = 0; redValue < 2; x++) {
//inside nested loop to traverse the image from left to right
for (int count = 1; count < 9; count++) {
targetPixel =
decodepic.getPixel(count + (8 * x), 0);
//gets the x,y coordinate of the target pixel
pixelColor = targetPixel.getColor();
//gets the color of the target pixel
redValue = pixelColor.getRed();
if (redValue == 1) {
if (count == 1) {
sum = sum + 128;
}
if (count == 2) {
sum = sum + 64;
}
if (count == 3) {
sum = sum + 32;
}
if (count == 4) {
sum = sum + 16;
}
if (count == 5) {
sum = sum + 8;
}
if (count == 6) {
sum = sum + 4;
}
if (count == 7) {
sum = sum + 2;
}
if (count == 8) {
sum = sum + 1;
}
}
System.out.println(sum);
}
System.out.println((char)sum);
sum = 0;
} //end of the inner for loop
}
}
public class HideMessageTester {
public static void main(String[] args) {
int[] bitArray =
{ 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1,
0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0,
1, 1, 1, 1, 0, 0, 1 };
//int[] bitArray =
{ 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1,
0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1,
1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0,
0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1,
0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0,
0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1,
0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1,
0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0,
0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1,
0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1,
1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0,
0, 1, 0, 0, 0, 0, 1};
Picture stegoObject = new Picture("Earth.bmp");
HideMessage stego = new HideMessage();
stego.encodeMessage(stegoObject, bitArray);
Picture decodeObject = new Picture("SecretMessage.bmp");
System.out.println("Now Decoding");
stego.decodeMessage(decodeObject);
}
}
First, some general pieces of advice: I think your program is overly complicated because the functions are commingling their responsibilities:
Picture stegoObject = new Picture("Earth.bmp");
HideMessage stego = new HideMessage();
stego.encodeMessage(stegoObject, bitArray);
Picture decodeObject = new Picture("SecretMessage.bmp");
System.out.println("Now Decoding");
stego.decodeMessage(decodeObject);
I was very surprised to see SecretMessage.bmp; it wasn't at all obvious that were trying to decode the object you had just created. Sure, upon reading the encodeMessage() method it was easy enough to determine where it came from, but I think this flow would have been easier:
/* encode */
Picture pic_to_steg = new Picture("foo.bmp");
HideMessage stego = new HideMessage();
Picture secret = stego.encodeMessage(pic_to_steg, bitArray);
secret.write("SecretMessage.bmp");
/* decode */
Picture pic_with_message = new Picture("SecretMessage.bmp");
int[] hidden = stego.decodeMessage(pic_with_message);
/* output `hidden` and compare against `bitArray` */
In other words: leave the file IO entirely up to the main flow of the program. Perhaps your routines will be called from a network server in the future, and the pictures will never be saved to disk. That modification will be far easier if the routines operate on Pictures and return amended Pictures and int[].
Can you test your encodeMessage() method in isolation? Perhaps look at the differences in what it does between an input file and an output file. This section looks troublesome:
public void encodeMessage(Picture stegoObject, int[] binaryArray) {
Pixel pixelTarget = new Pixel(stegoObject, 0, 0);
Pixel[] pixelArray = stegoObject.getPixels();
Color pixelColor = null;
int redValue = 0;
for (int x = 0; x < binaryArray.length; x++) {
redValue = binaryArray[x];
pixelTarget = pixelArray[x];
pixelTarget.setRed(redValue);
}
pixelTarget = pixelArray[binaryArray.length];
pixelTarget.setRed(255);
Is the pixelArray really a reference into the image that can be updated through simple assignment? I'd really expect the design to look more like this pseudo-code:
pixel p = image.getPixel(x, y);
p.setred(binaryArray[i]);
image.setPixel(x, y, p);
The decoding has some strange loops:
for (int x = 0; redValue < 2; x++) {
//inside nested loop to traverse the image from left to right
for (int count = 1; count < 9; count++) {
This loop might work exactly as you designed it, but upon a first reading, it feels very wrong: You start with x=0, you increment x each time through the loop, but you use redValue < 2 as your loop termination rule.
I would so much rather see the loop written like this:
int x = 0;
while (redValue < 2) {
/* stuff */
x++;
}
(It isn't identical; x is still valid outside the loop, which can be dangerous. However, I think this is much more clear.)
There are cases where the termination clause of a for loop isn't related to the setup or increment clauses -- in my experience, they are very rare.
In this case though, it feels like a mistake; the condition redValue < 2 a loop invariant, but the inner loop assumes it will only happen on pixels that are multiples of 8, which is an assumption that is not enforced in the encodeMessage() method.
Trying to compute an integer value from your redValues as you read them is needlessly complicating your decode routine. I suggest removing the inner loop and return an array exactly like the array passed into the encodeMessage() routine. This will be (a) easier (b) easier to debug (c) easier to test (d) a thousand times easier to handle writing bit arrays that aren't evenly divisible by 8.
Then write a second method that turns the bit array output into the sum, or ASCII characters, or EBCDIC characters, or RSA key parameters, or whatever it is that's being encoded. Don't try to do too much at once. Writing a separate method to decode the array of bits will be (a) easier (b) easier to debug (c) easier to test (d) thousand time easier to handle arbitrary output modifications.
I hope these hints help.