Recursive H Tree

Overview

This project is a visualization of a computer programming concept: Recursion. An H Tree is a fractal pattern that also has practical use in the layout of circuits inside of computer processors.

Recursion

Recursion is a strange concept at first to wrap your head around. It's the concept of calling on yourself, similar to a loop. If you've ever watched someone watching tv on tv, then you have sort of seen a form of recursion.

Java Code

	import edu.princeton.cs.algs4.StdDraw;

	public class RecursiveGraphic {
		public static int canvasSize = 256;
		public static int size = canvasSize /2;
		
		public static void main(String[]args)
		{
			StdDraw.setCanvasSize();
			StdDraw.setScale(0,canvasSize);
			StdDraw.setPenColor(0,0,0);
			StdDraw.setPenRadius(.001);
			htree(Integer.parseInt(args[0]), canvasSize/2, canvasSize/2, size);
		}
		
		public static void drawH(double x, double y, double size)
		{
			double newX = x -(size/2);
			StdDraw.line(newX, y, newX + size, y);
			StdDraw.line(newX, y-(size/2), newX, y+(size/2));
			StdDraw.line(newX+size, y-(size/2), newX + size, y + (size/2));
			StdDraw.show(020);
		}
		
		public static void htree(int n, double x, double y, double size)
		{
			if(n>1)
			{
				System.out.print(n + " ");
				drawH(x, y, size);
				htree(n-1, x-size/2, y+size/2, size/2);
				htree(n-1, x-size/2, y-size/2, size/2);
				htree(n-1, x + size/2, y + size/2, size/2);
				htree(n-1, x + size/2, y - size/2, size/2);
			}
			if(n==1)
			{
				System.out.print(n + " ");
				drawH(x, y, size);
			}
		}	
	}

Technologies Used

  • Java
  • Eclipse
  • GitHub
  • Princeton StdDraw

View on GitHub

GitHub