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How to add an image into a hexagon in a hexagonal grid?

I have a problem with a hexagonal grid. I found this code you can see below on Internet, so it's not mine. There are two public classes: hexgame which generates the grid and hexmech which draws and fills every single hexagon. What I'd like to do is basically insert an image into a specific hexagon, but I don't know how to code this and in which part of the classes I should put it. Am I thinking the wrong way?
Thank you very much for your help!
Hexgame
package hex;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class hexgame
{
private hexgame() {
initGame();
createAndShowGUI();
}
final static Color COLOURBACK = Color.WHITE;
final static Color COLOURCELL = Color.WHITE;
final static Color COLOURGRID = Color.BLACK;
final static Color COLOURONE = new Color(255,255,255,200);
final static Color COLOURONETXT = Color.BLUE;
final static Color COLOURTWO = new Color(0,0,0,200);
final static Color COLOURTWOTXT = new Color(255,100,255);
final static Color COLOURSAFE = Color.WHITE;
final static Color COLOURDANGEROUS = Color.LIGHT_GRAY;
final static int EMPTY = 0;
final static int UNKNOWN = -1;
final static int SAFE = 1;
final static int DANGEROUS = 2;
final static int CLICKED = 3;
final static int COLUMN_SIZE = 23;
final static int ROW_SIZE = 14;
final static int HEXSIZE = 45;
final static int BORDERS = 15;
int[][] board = new int[COLUMN_SIZE][ROW_SIZE];
void initGame(){
hexmech.setXYasVertex(false);
hexmech.setHeight(HEXSIZE);
hexmech.setBorders(BORDERS);
for (int i=0;i<COLUMN_SIZE;i++) {
for (int j=0;j<ROW_SIZE;j++) {
board[i][j]=EMPTY;
}
}
board[5][5] = SAFE;
board[5][6] = SAFE;
board[5][7] = SAFE;
board[6][5] = SAFE;
board [6][6] = SAFE;
board[4][4] = UNKNOWN;
}
private void createAndShowGUI()
{
DrawingPanel panel = new DrawingPanel();
JFrame frame = new JFrame("Hex Testing 4");
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
Container content = frame.getContentPane();
content.add(panel);
frame.setSize(825, 630);
frame.setResizable(true);
frame.setLocationRelativeTo( null );
frame.setVisible(true);
}
class DrawingPanel extends JPanel
{
public DrawingPanel()
{
setBackground(COLOURBACK);
MyMouseListener ml = new MyMouseListener();
addMouseListener(ml);
}
public void paintComponent(Graphics g)
{
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g.setFont(new Font("TimesRoman", Font.PLAIN, 15));
super.paintComponent(g2);
for (int i=0;i<COLUMN_SIZE;i++) {
for (int j=0;j<ROW_SIZE;j++) {
if (board[i][j] != UNKNOWN)
hexmech.drawHex(i,j,g2);
}
}
for (int i=0;i<COLUMN_SIZE;i++) {
for (int j=0;j<ROW_SIZE;j++) {
if (board[i][j] != UNKNOWN)
hexmech.fillHex(i,j,board[i][j],g2);
}
}
}
class MyMouseListener extends MouseAdapter {
public void mouseClicked(MouseEvent e) {
int x = e.getX();
int y = e.getY();
Point p = new Point( hexmech.pxtoHex(e.getX(),e.getY()) );
if (p.x < 0 || p.y < 0 || p.x >= COLUMN_SIZE || p.y >= ROW_SIZE) return;
board[p.x][p.y] = CLICKED;
repaint();
}
}
}
}
Hexmech
package hex;
import java.awt.*;
import javax.swing.*;
public class hexmech
{
#define HEXEAST 0
#define HEXSOUTHEAST 1
#define HEXSOUTHWEST 2
#define HEXWEST 3
#define HEXNORTHWEST 4
#define HEXNORTHEAST 5
public final static boolean orFLAT= true;
public final static boolean orPOINT= false;
public static boolean ORIENT= orFLAT;
public static boolean XYVertex=true;
private static int BORDERS=50
private static int s=0; // length of one side
private static int t=0; // short side of 30o triangle outside of each hex
private static int r=0; // radius of inscribed circle (centre to middle of each side). r= h/2
private static int h=0; // height. Distance between centres of two adjacent hexes. Distance between two opposite sides in a hex.
public static void setXYasVertex(boolean b) {
XYVertex=b;
}
public static void setBorders(int b){
BORDERS=b;
}
public static void setSide(int side) {
s=side;
t = (int) (s / 2); //t = s sin(30) = (int) CalculateH(s);
r = (int) (s * 0.8660254037844);
h=2*r;
}
public static void setHeight(int height) {
h = height;
r = h/2; // r = radius of inscribed circle
s = (int) (h / 1.73205); // s = (h/2)/cos(30)= (h/2) / (sqrt(3)/2) = h / sqrt(3)
t = (int) (r / 1.73205); // t = (h/2) tan30 = (h/2) 1/sqrt(3) = h / (2 sqrt(3)) = r / sqrt(3)
}
public static Polygon hex (int x0, int y0) {
int y = y0 + BORDERS;
int x = x0 + BORDERS;
if (s == 0 || h == 0) {
System.out.println("ERROR: size of hex has not been set");
return new Polygon();
}
int[] cx,cy;
if (XYVertex)
cx = new int[] {x,x+s,x+s+t,x+s,x,x-t}; //this is for the top left vertex being at x,y. Which means that some of the hex is cutoff.
else
cx = new int[] {x+t,x+s+t,x+s+t+t,x+s+t,x+t,x}; //this is for the whole hexagon to be below and to the right of this point
cy = new int[] {y,y,y+r,y+r+r,y+r+r,y+r};
return new Polygon(cx,cy,6);
}
public static void drawHex(int i, int j, Graphics2D g2) {
int x = i * (s+t);
int y = j * h + (i%2) * h/2;
Polygon poly = hex(x,y);
g2.setColor(hexgame.COLOURCELL);
//g2.fillPolygon(hexmech.hex(x,y));
g2.fillPolygon(poly);
g2.setColor(hexgame.COLOURGRID);
g2.drawString(String.format("%c;%d", 'A'+i, j+1), x+20, y+40);
g2.drawPolygon(poly);
}
public static void fillHex(int i, int j, int n, Graphics2D g2) {
char c='o';
int x = i * (s+t);
int y = j * h + (i%2) * h/2;
/*if (n < 0) {
g2.setColor(hexgame.COLOURONE);
g2.fillPolygon(hex(x,y));
g2.setColor(hexgame.COLOURONETXT);
c = (char)(-n);
g2.drawString(""+c, x+r+BORDERS, y+r+BORDERS+4); //FIXME: handle XYVertex
//g2.drawString(x+","+y, x+r+BORDERS, y+r+BORDERS+4);
}
if (n > 0) {
g2.setColor(hexgame.COLOURTWO);
g2.fillPolygon(hex(x,y));
g2.setColor(hexgame.COLOURTWOTXT);
c = (char)n;
if (n==3) {
g2.setColor(hexgame.COLOURTWO);
g2.fillPolygon(hex(x,y));
g2.setColor(hexgame.COLOURTWOTXT);
}
}
public static Point pxtoHex(int mx, int my) {
Point p = new Point(-1,-1);
//correction for BORDERS and XYVertex
mx -= BORDERS;
my -= BORDERS;
if (XYVertex) mx += t;
int x = (int) (mx / (s+t));
int y = (int) ((my - (x%2)*r)/h);
int dx = mx - x*(s+t);
int dy = my - y*h;
if (my - (x%2)*r < 0) return p; // prevent clicking in the open halfhexes at the top of the screen
//System.out.println("dx=" + dx + " dy=" + dy + " > " + dx*r/t + " <");
//even columns
if (x%2==0) {
if (dy > r) { //bottom half of hexes
if (dx * r /t < dy - r) {
x--;
}
}
if (dy < r) { //top half of hexes
if ((t - dx)*r/t > dy ) {
x--;
y--;
}
}
} else { // odd columns
if (dy > h) { //bottom half of hexes
if (dx * r/t < dy - h) {
x--;
y++;
}
}
if (dy < h) { //top half of hexes
//System.out.println("" + (t- dx)*r/t + " " + (dy - r));
if ((t - dx)*r/t > dy - r) {
x--;
}
}
}
p.x=x;
p.y=y;
return p;
}

In your implementation of paintComponent(), invoke setClip() with a suitable Shape, such as Polygon. You can size and translate the Polygon to match the destination hexagon using the createTransformedShape() method of AffineTransform. Use the coordinates of the polygon's boundary as the basis for the coordinates used in your call to drawImage(). A related example using Ellipse2D is shown here.

Graphics paint component and loop trouble

I can not seem to figure out why my concentric circles are not lining up. My loops seem correct to me and the measurements are correct but for some reason the last few circles are off-centered. That's the first issue I'm having. The second issue is, i can't seem to get the concentric circles to print in each square. Once again, i can't seem to find any issue in my logic, but obviously there is an issue. Any help on this at all would be great.
This should be the end product
*Now this is my source code- ExampleGUI.java *
import javax.swing.*;
public class ExampleGUI {
public static void main(String args []) {
JFrame frame = new JFrame("Example Graphics");
ExamplePanel panel = new ExamplePanel();
frame.getContentPane().add(panel);
frame.setDefaultCloseOperation(3);
frame.pack();
frame.setVisible(true);
}
}
* ExamplePanel.java *
import java.awt.*;
import javax.swing.*;
public class ExamplePanel extends JPanel{
public ExamplePanel() {
setPreferredSize(new Dimension (600, 600));
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
int x = 0;
int x2 = 5;
int y = 500;
int y2 = 505;
int w = 100;
int w2 = 90;
int h = 100;
int h2 = 90;
int i, j, k;
for(j = 1; j < 7; j++) {
x = 0;
x2 = x + 5;
for(i = 1; i < 7; i++) {
if ((i + j) % 2 == 0) {
g.setColor(Color.white);
} else {
g.setColor(Color.yellow);
}
g.fillRect(x, y, w, h);
g.setColor(Color.black);
g.drawRect(x, y, w, h);
g.setColor(Color.green);
g.fillOval(x2, y2, w2, h2);
for(k = 1; k < 7; k++) {
g.setColor(Color.black);
g.drawOval(x2, y2, w2, h2);
x2 = x2 + 5;
y2 = y2 + 5;
w2 = w2 - 10;
h2 = h2 - 10;
}
x = x + w;
x2 = x2 + w2 + 10;
}
x = x + w;
y = y - h;
y2 = (y2 - h2) - 10;
}
}
}
* This is what my program looks like when i run it. It doesn't look like the other picture for some reason *

Basically, you "spiral" loop is modifying the state of variables that are required elsewhere
What I would do, is create a new series of variables, initialized to the current state and modify those instead...
int ix = x2;
int iy = y2;
int ih = h2;
int iw = w2;
for (k = 1; k < 7; k++) {
g.setColor(Color.black);
g.drawOval(ix, iy, iw, ih);
ix = ix + 5;
iy = iy + 5;
iw = iw - 10;
ih = ih - 10;
}

Parabolas within bounds

I have a JPanel 200x200.
I trying to create a function that will generate random parabola's with the bounds of the JPanel, with a constraint that the height can't be lower than a 100 (middle of the screen), I basically want to move a shape around these parabolas
Here is some code I'm using to get started:
Random random = new Random(); int y; int x;
int size = random.nextInt(10);
int translation = random.nextInt(50);
int height = random.nextInt(100) - 200; //between 100 and 200
//Parabola functions : y = ((x/7 - 30))^2
// x and y are coordiates of where the shape is drawn
while(y != 200){
y = (float)Math.pow((float)xloc / size - translation ,2) + height;
x++;
}
I've been researching about FlatteningPathIterator but not too sure how to use them. my function
y = (float)Math.pow((float)xloc / size - translation ,2) + height;`
prints parabola's sometimes outside the bounds, how would i edit it to print parabola's inside the bounds?

There is a Java Swing shape generator for this called Quad2dCurve. The getPathIterator call gives you an enumerator for points on the curve.
Here is some example code:
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.Random;
import javax.swing.*;
final class TestCanvas extends JComponent {
int size = 200;
int n = 10;
float[] ph = new float[n];
float[] pw = new float[n];
float[] px = new float[n];
Random gen = new Random();
TestCanvas() {
makeRandomParabolas();
setFocusable(true);
addKeyListener(new KeyAdapter() {
#Override
public void keyPressed(KeyEvent e) {
makeRandomParabolas();
repaint();
float [] coords = new float [6];
for (int i = 0; i < n; i++) {
PathIterator pi = getQuadCurve(i).getPathIterator(null, 0.1);
System.out.print(i + ":");
while (!pi.isDone()) {
switch (pi.currentSegment(coords)) {
case PathIterator.SEG_MOVETO:
System.out.print(" move to");
break;
case PathIterator.SEG_LINETO:
System.out.print(" line to");
break;
default:
System.out.print(" unexpected");
break;
}
System.out.println(" (" + coords[0] + "," + coords[1]+")");
pi.next();
}
System.out.println();
}
}
});
}
QuadCurve2D.Float getQuadCurve(int i) {
return new QuadCurve2D.Float(px[i] - pw[i], size,
px[i], size - (2 * ph[i]),
px[i] + pw[i], size);
}
void makeRandomParabolas() {
for (int i = 0; i < n; i++) {
float x = 0.2f + 0.6f * gen.nextFloat();
px[i] = size * x;
pw[i] = size * (Math.min(x, 1 - x) * gen.nextFloat());
ph[i] = size * (0.5f + 0.5f * gen.nextFloat());
}
}
#Override
protected void paintComponent(Graphics g0) {
Graphics2D g = (Graphics2D) g0;
for (int i = 0; i < n; i++) {
g.draw(getQuadCurve(i));
}
}
}
public class Main extends JFrame {
public Main() {
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
getContentPane().add(new TestCanvas());
getContentPane().setPreferredSize(new Dimension(200, 200));
pack();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Main().setVisible(true);
}
});
}
}

How do I draw rectangles in jpanel based on calculated averages

I have a gui where data is entered and the averages are calculated for 5 different sets of data. These are stored in an array with the five averages in the five positions.
How do I make it draw rectangles in a jpanel to look like a graph of those 5 averages ?

..make it draw rectangles in a jpanel to look like a graph...
Assuming, youre talking about bar graph,
Have a look at this example :
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class SimpleBarChart extends JPanel {
private double[] value;
private String[] languages;
private String title;
public SimpleBarChart(double[] val, String[] lang, String t) {
languages = lang;
value = val;
title = t;
}
#Override
public void paintComponent(Graphics graphics) {
super.paintComponent(graphics);
if (value == null || value.length == 0) {
return;
}
double minValue = 0;
double maxValue = 0;
for (int i = 0; i < value.length; i++) {
if (minValue > value[i]) {
minValue = value[i];
}
if (maxValue < value[i]) {
maxValue = value[i];
}
}
Dimension dim = getSize();
int clientWidth = dim.width;
int clientHeight = dim.height;
int barWidth = clientWidth / value.length;
Font titleFont = new Font("Book Antiqua", Font.BOLD, 15);
FontMetrics titleFontMetrics = graphics.getFontMetrics(titleFont);
Font labelFont = new Font("Book Antiqua", Font.PLAIN, 10);
FontMetrics labelFontMetrics = graphics.getFontMetrics(labelFont);
int titleWidth = titleFontMetrics.stringWidth(title);
int q = titleFontMetrics.getAscent();
int p = (clientWidth - titleWidth) / 2;
graphics.setFont(titleFont);
graphics.drawString(title, p, q);
int top = titleFontMetrics.getHeight();
int bottom = labelFontMetrics.getHeight();
if (maxValue == minValue) {
return;
}
double scale = (clientHeight - top - bottom) / (maxValue - minValue);
q = clientHeight - labelFontMetrics.getDescent();
graphics.setFont(labelFont);
for (int j = 0; j < value.length; j++) {
int valueP = j * barWidth + 1;
int valueQ = top;
int height = (int) (value[j] * scale);
if (value[j] >= 0) {
valueQ += (int) ((maxValue - value[j]) * scale);
} else {
valueQ += (int) (maxValue * scale);
height = -height;
}
graphics.setColor(Color.blue);
graphics.fillRect(valueP, valueQ, barWidth - 2, height);
graphics.setColor(Color.black);
graphics.drawRect(valueP, valueQ, barWidth - 2, height);
int labelWidth = labelFontMetrics.stringWidth(languages[j]);
p = j * barWidth + (barWidth - labelWidth) / 2;
graphics.drawString(languages[j], p, q);
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setSize(350, 300);
double[] value = new double[5];
String[] languages = new String[5];
value[0] = 1;
languages[0] = "Visual Basic";
value[1] = 2;
languages[1] = "PHP";
value[2] = 3;
languages[2] = "C++";
value[3] = 4;
languages[3] = "C";
value[4] = 5;
languages[4] = "Java";
frame.getContentPane().add(new SimpleBarChart(value, languages,
"Programming Languages"));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
Also see JFreeChart and if you dont mind using an external library.
Example that you might need via #trashGod : example and its source code.

How do I divide a picture into 4 sections and change each section?

In the body of the Picture class create a new public method named "specialEffect" that has return type void and takes no parameters.
The method should contain four loops that each iterate over the pixels of an image in such a way that each loop iterates through 1/4 of the total number of pixels and performs a different effect as follows:
The first loop is to apply an effect that removes the both the blue and green component from each pixel leaving the red component unchanged.
The next loop continuing from where the last left off is to remove the blue and red component from each pixel leaving the green component unchanged.
The next loop continuing from where the last left off it to remove the green and red component from each pixel leaving the blue component unchanged.
The final loop continuing from where the last off is to convert each pixel to greyscale.
How would I go about doing that? I only know how to divide it in half and change the top part.. not sure how to go about doing sections.
Thanks!

The code below produces this picture:
private static BufferedImage specialEffect(BufferedImage in) {
BufferedImage out = new BufferedImage(in.getWidth(), in.getHeight(),
BufferedImage.TYPE_INT_ARGB);
for (int x = 0; x < out.getWidth() / 2; x++) {
for (int y = 0; y < out.getHeight() / 2; y++) {
Color c = new Color(in.getRGB(x, y));
out.setRGB(x, y, new Color(c.getRed(), 0, 0).getRGB());
}
}
for (int x = out.getWidth() / 2; x < out.getWidth(); x++) {
for (int y = 0; y < out.getHeight() / 2; y++) {
Color c = new Color(in.getRGB(x, y));
out.setRGB(x, y, new Color(0, c.getGreen(), 0).getRGB());
}
}
for (int x = 0; x < out.getWidth() / 2; x++) {
for (int y = out.getHeight() / 2; y < out.getHeight(); y++) {
Color c = new Color(in.getRGB(x, y));
out.setRGB(x, y, new Color(0, 0, c.getBlue()).getRGB());
}
}
for (int x = out.getWidth() / 2; x < out.getWidth(); x++) {
for (int y = out.getHeight() / 2; y < out.getHeight(); y++) {
Color c = new Color(in.getRGB(x, y));
int m = Math.max(c.getRed(),Math.max(c.getGreen(),c.getBlue()));
out.setRGB(x, y, new Color(m, m, m).getRGB());
}
}
return out;
}
public static void main(String[] args) throws IOException {
JFrame frame = new JFrame("Test");
frame.add(new JComponent() {
BufferedImage image = specialEffect(ImageIO.read(new URL("http://upload.wikimedia.org/wikipedia/en/2/24/Lenna.png")));
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, this);
}
});
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
frame.setVisible(true);
}

I am assuming that your Picture class has the following methods:
int getNumberOfPixels()
float getRValueOfNthPixel(int n)
float getGValueOfNthPixel(int n)
float getBValueOfNthPixel(int n)
void setRValueOfNthPixel(int n, float r)
void setGValueOfNthPixel(int n, float g)
void setBValueOfNthPixel(int n, float b)
If the number of pixels is always a multiple of 4, then one possible implementation of "specialEffect" method would be:
public void specialEffect() {
int n = getNumberOfPixels();
int limit1 = 1 * n / 4;
int limit2 = 2 * n / 4;
int limit3 = 3 * n / 4;
int limit4 = 4 * n / 4;
/*
* The first loop is to apply an effect that removes the both the blue
* and green component from each pixel leaving the red component
* unchanged.
*/
for (int i = 0; i < limit1; i++) {
setBValueOfNthPixel(i, 0);
setGValueOfNthPixel(i, 0);
}
/*
* The next loop continuing from where the last left off is to remove
* the blue and red component from each pixel leaving the green
* component unchanged.
*/
for (int i = limit1; i < limit2; i++) {
setBValueOfNthPixel(i, 0);
setRValueOfNthPixel(i, 0);
}
/*
* The next loop continuing from where the last left off it to remove
* the green and red component from each pixel leaving the blue
* component unchanged.
*/
for (int i = limit2; i < limit3; i++) {
setGValueOfNthPixel(i, 0);
setRValueOfNthPixel(i, 0);
}
/*
* The final loop continuing from where the last off is to convert each
* pixel to greyscale.
*/
for (int i = limit3; i < limit4; i++) {
float grayValue = (getRValueOfNthPixel(i)
+ getGValueOfNthPixel(i)
+ getBValueOfNthPixel(i)) / 3;
setRValueOfNthPixel(i, grayValue);
setGValueOfNthPixel(i, grayValue);
setBValueOfNthPixel(i, grayValue);
}
}