Java GUI program to convert 2D array value into graphic

Question

I am a beginner in Java & i have to make a java program that takes the input from a 2d array with dimensions 347*697 (array's value range from 2200 to 4200 ). I have to do such that for every 100 increase in range there is a set of specific color(for e.g 2200-2300 color(214,217,223) & so on). I have never done anything .. & this is the program i found little bit similar ... Can anyone give me idea how to convert it I know its too much to ask for , but tomorrow i have to give a ppt. & when every option is closed i came here. Please guys, I need help badly

import javax.swing.*;
import java.awt.*;
import java.util.Random;

public class Map extends JPanel {

public static final Color CITY = new Color(214,217,223);
public static final Color DESERT = new Color(255,204,102);
public static final Color DIRT_ROAD = new Color(153,102,0);
public static final Color FOREST = new Color(0,102,0);
public static final Color HILLS = new Color(51,153,0);
public static final Color LAKE = new Color(0,153,153);
public static final Color MOUNTAINS = new Color(102,102,255);
public static final Color OCEAN = new Color(0,0,153);
public static final Color PAVED_ROAD = new Color(51,51,0);
public static final Color PLAINS = new Color(102,153,0);

public static final Color[] TERRAIN = {
    CITY,
    DESERT,
    DIRT_ROAD,
    FOREST,
    HILLS,
    LAKE,
    MOUNTAINS,
    OCEAN,
    PAVED_ROAD,
    PLAINS
};

public static final int NUM_ROWS = 215;
public static final int NUM_COLS = 300;

public static final int PREFERRED_GRID_SIZE_PIXELS = 10;

// In reality you will probably want a class here to represent a map tile,
// which will include things like dimensions, color, properties in the
// game world.  Keeping simple just to illustrate.
private final Color[][] terrainGrid;

public Map(){
    this.terrainGrid = new Color[NUM_ROWS][NUM_COLS];
    Random r = new Random();
    // Randomize the terrain
    for (int i = 0; i < NUM_ROWS; i++) {
        for (int j = 0; j < NUM_COLS; j++) {
            int randomTerrainIndex = r.nextInt(TERRAIN.length);
            Color randomColor = TERRAIN[randomTerrainIndex];
            this.terrainGrid[i][j] = randomColor;
        }
    }
    int preferredWidth = NUM_COLS * PREFERRED_GRID_SIZE_PIXELS;
    int preferredHeight = NUM_ROWS * PREFERRED_GRID_SIZE_PIXELS;
    setPreferredSize(new Dimension(preferredWidth, preferredHeight));
}

@Override
public void paintComponent(Graphics g) {
    // Important to call super class method
    super.paintComponent(g);
    // Clear the board
    g.clearRect(0, 0, getWidth(), getHeight());
    // Draw the grid
    int rectWidth = getWidth() / NUM_COLS;
    int rectHeight = getHeight() / NUM_ROWS;

    for (int i = 0; i < NUM_ROWS; i++) {
        for (int j = 0; j < NUM_COLS; j++) {
            // Upper left corner of this terrain rect
            int x = i * rectWidth;
            int y = j * rectHeight;
            Color terrainColor = terrainGrid[i][j];
            g.setColor(terrainColor);
            g.fillRect(x, y, rectWidth, rectHeight);
        }
    }
}

public static void main(String[] args) {
    // http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            JFrame frame = new JFrame("Game");
            Map map = new Map();
            frame.add(map);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.pack();
            frame.setVisible(true);
        }
    });
}

}

This question appears to be off-topic because it is primarily a work or homework dump. — Hovercraft Full Of Eels, Jul 06 '14 at 13:44
@HovercraftFullOfEels I just need logic how can i use different colors for different values in an Array ... I don't want you to solve it dude ..Trust me its really important, & i just need a bit of help — Shirish, Jul 06 '14 at 13:47
Trust me, it's important to us that you show the fruits of your efforts. This is not a site to do your homework for you. — Hovercraft Full Of Eels, Jul 06 '14 at 13:51
I'm sorry you feel that way. Myself, I'm much more receptive to questions that show some effort, rather than simply dumping "found" code and throwing up the hands, that show **your** code attempt, that ask specific questions about **your** code attempt. That's just how I am. — Hovercraft Full Of Eels, Jul 06 '14 at 14:03
@HovercraftFullOfEels I already clarified it that i don't know java applets and GUI & the code output was also to explain everyone understand what i have in my mind(coz i m unaware of terms). I knew that i will encounter someone like you too... who will constantly remind me of my fault of not knowing this language instead of helping. U meant it or not, but none offense taken here.. take care mate :) — Shirish, Jul 06 '14 at 14:16

score 0 · Accepted Answer · edited May 23 '17 at 12:05

0

Create a byte[] with the rgb values for each pixel of the image you want. The byte[] length will be width * height * 3 (3 values for each pixel). Look at this for an example of how create a BufferedImage from the byte[].

Another alternative is to create a BufferedImage and set the rgb value for each pixel directly. In this case, you have to bit twiddle all 3 rgb values into a single int value.

edited May 23 '17 at 12:05

Community

1
1

answered Jul 06 '14 at 13:48

Brett Okken

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Second method u suggested , Can i define value of rgb to a range of values also by using a for loop? – Shirish Jul 06 '14 at 13:55
You must set the specific rgb value for each pixel. This would likely be done from within nested for loops over width and height. – Brett Okken Jul 06 '14 at 14:03
Thanks for your help. Now i know what i have to do. Thanks again :) – Shirish Jul 06 '14 at 14:10

Java GUI program to convert 2D array value into graphic

1 Answers1