L-Systems Dragon Curve Fractal in Java

I just love generative art and fractals. I made another fractal called Dragon Curve in Java. In this post I will share the code for the fractal.

Here's the code

	package dragon;
	import java.awt.Color;
	import java.awt.Graphics;
	import java.awt.Graphics2D;
	import java.awt.GraphicsConfiguration;
	import java.awt.GraphicsDevice;
	import java.awt.GraphicsEnvironment;
	import java.awt.image.BufferedImage;
	import java.io.File;
	import java.io.FileOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;
	import javax.imageio.ImageIO;
	public final class DragonCurve {
	private BufferedImage img = null;
	private int IMG_WIDTH;
	private int IMG_HEIGHT;
	private GraphicsEnvironment ge = null;
	private GraphicsDevice gd = null;
	private GraphicsConfiguration gc = null;
	public DragonCurve() {
	IMG_WIDTH = 1400;
	IMG_HEIGHT = 1400;
	ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
	gd = ge.getDefaultScreenDevice();
	gc = gd.getDefaultConfiguration();
	}
	private void createDragonFractal() {
	Graphics g = null;
	Graphics2D g2d = (Graphics2D) g;
	img = gc.createCompatibleImage(IMG_WIDTH, IMG_HEIGHT);
	g2d = img.createGraphics();
	g2d.setColor(Color.black);
	g2d.fillRect(0, 0, IMG_WIDTH, IMG_HEIGHT);
	g2d.setColor(Color.red);
	dragonRecur(300, 500, 1000, 1100, 20, g2d);
	g2d.drawImage(img, 0, 0, null);
	g2d.dispose();
	writeImage();
	}
	private void writeImage() {
	File file = new File("pic.png");
	try {
	file.createNewFile();
	OutputStream out = new FileOutputStream(file);
	ImageIO.write(img, "png", out);
	out.close();
	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	private void dragonRecur(int x1, int y1, int x2, int y2, int k,
	Graphics2D g2d) {
	if (k > 0) {
	int xn = (x1 + x2) / 2 + (y2 - y1) / 2;
	int yn = (y1 + y2) / 2 - (x2 - x1) / 2;
	dragonRecur(x2, y2, xn, yn, k - 1, g2d);
	dragonRecur(x1, y1, xn, yn, k - 1, g2d);
	} else {
	g2d.drawLine(x1, y1, x2, y2);
	}
	}
	public static void main(String... strings) {
	new DragonCurve().createDragonFractal();
	}
	}

view raw DragonCurve.java hosted with ❤ by GitHub

Image generated

 

I simply modified it a bit again and got something like following :- 

 

Code for the modified one is as follows :- 

	package dragon;
	import java.awt.AlphaComposite;
	import java.awt.Color;
	import java.awt.Font;
	import java.awt.Graphics;
	import java.awt.Graphics2D;
	import java.awt.GraphicsConfiguration;
	import java.awt.GraphicsDevice;
	import java.awt.GraphicsEnvironment;
	import java.awt.RenderingHints;
	import java.awt.image.BufferedImage;
	import java.io.File;
	import java.io.FileOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;
	import javax.imageio.ImageIO;
	public final class DragonCurve {
	private BufferedImage img = null;
	private int IMG_WIDTH;
	private int IMG_HEIGHT;
	private GraphicsEnvironment ge = null;
	private GraphicsDevice gd = null;
	private GraphicsConfiguration gc = null;
	private Graphics2D g2d;
	public DragonCurve() {
	IMG_WIDTH = 1400;
	IMG_HEIGHT = 1400;
	ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
	gd = ge.getDefaultScreenDevice();
	gc = gd.getDefaultConfiguration();
	}
	private void createDragonFractal() {
	Graphics g = null;
	g2d = (Graphics2D) g;
	img = gc.createCompatibleImage(IMG_WIDTH, IMG_HEIGHT);
	g2d = img.createGraphics();
	g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
	RenderingHints.VALUE_INTERPOLATION_BICUBIC);
	g2d.setColor(Color.black);
	g2d.fillRect(0, 0, IMG_WIDTH, IMG_HEIGHT);
	g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
	.8f));
	dragonRecur(300, 500, 1000, 1100, 15, g2d);
	g2d.setFont(new Font("Courier New", Font.BOLD, 40));
	g2d.drawString("Dragon Fractal", 100, 1100);
	g2d.drawString("By Psycho_Coder", 100, 1200);
	g2d.drawImage(img, 0, 0, null);
	g2d.dispose();
	writeImage();
	}
	private void writeImage() {
	File file = new File("dragon_fractal.png");
	try {
	file.createNewFile();
	OutputStream out = new FileOutputStream(file);
	ImageIO.write(img, "png", out);
	out.close();
	} catch (IOException e) {
	e.printStackTrace();
	}
	}
	private void dragonRecur(int x1, int y1, int x2, int y2, int k,
	Graphics2D g2d) {
	if (k > 0) {
	int xn = (x1 + x2) / 2 + (y2 - y1) / 2;
	int yn = (y1 + y2) / 2 - (x2 - x1) / 2;
	dragonRecur(x2, y2, xn, yn, k - 1, g2d);
	g2d.setColor(Color.red);
	g2d.drawLine(x1, y1, x2, y2);
	dragonRecur(x1, y1, xn, yn, k - 1, g2d);
	} else {
	g2d.setColor(Color.white);
	g2d.drawLine(x1, y1, x2, y2);
	}
	}
	public static void main(String... strings) {
	new DragonCurve().createDragonFractal();
	}
	}

view raw DragonCurve.java hosted with ❤ by GitHub

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