Question

If you search the web for fractal designs, you will find many inticate wonders beyond the Koch snowflake illustrated in this chapter. H-fractal, in which the repeated pattern is shaped hke an elongated letter H in which the horizontal bar and vertical lines on the sides have the same length. Thus, the order-0 Hfiactal looks like this: To create the order-l fractal, all you do is add four new H-fiactals-each one half of the original size-at each open end of the order-0 firactal, like this: To create the order-2 fractal, all you have to do is add even smaller H-fractals (again half the size of the fractal to which they connect) to each of the open endpoints. This process gives rise to the following order-2 fractal: 山|

/*
* File: HFractal.cpp
* ------------------
* This program draws an H-fractal on the graphics window.int main() {
*/
#include "gwindow.h"

/* Function prototypes */
void drawHFractal(GWindow & gw, double x, double y, double size, int order);

/* Main program */
int main() {
GWindow gw;
double xc = gw.getWidth() / 2;
double yc = gw.getHeight() / 2;
drawHFractal(gw, xc, yc, 100, 3);
return 0;
}

/*
* Function: drawHFractal
* Usage: drawHFractal(gw, x, y, size, order);
* -------------------------------------------
* Draws a fractal diagram consisting of an H in which each additional
* fractal layer draws half-size fractals at the four endpoints of each H.
*/
void drawHFractal(GWindow & gw, double x, double y, double size, int order) {
// @@@@
}

write a recursive function for @@@@

Answer 1

/*
* =====================================================================================
*
*       Filename: HFractal.cpp
*    Description: draw H-Fractal in which repeated pattern is shaped like
*    an elongated letter 'H'
*
* =====================================================================================
*/
#include <cmath>
#include <iostream>
#include "random.h"
#include "gwindow.h"

using namespace std;

void drawHFractal(GWindow gw, double x, double y, double size, int order);

//void drawHFractal(GWindow gw, double & x, double & y, double   size, int order);
int main(void)
{
    GWindow gw(600,600);
    double xc = gw.getWidth()/2;
    double yc = gw.getHeight()/2;
    drawHFractal(gw, xc, yc, 100, 3);

    return 0;
}

void drawHFractal(GWindow gw, double x, double y, double size, int order)
//void drawHFractal(GWindow gw, double & x, double & y, double   size, int order)
{
    int upleft_x = x - size/2;
    int upleft_y = y - size/2;
    int downright_x = x + size/2;
    int downright_y = y + size/2;
    gw.drawLine(upleft_x, upleft_y, upleft_x, downright_y );
    gw.drawLine(upleft_x, y, downright_x, y);
    gw.drawLine(downright_x, upleft_y, downright_x, downright_y);
    if(order == 0)
    {
        return;
    }
    drawHFractal(gw, upleft_x, upleft_y, size/2, order-1);
    drawHFractal(gw, upleft_x, downright_y, size/2, order-1);
    drawHFractal(gw, downright_x, upleft_y, size/2, order-1);
    drawHFractal(gw, downright_x, downright_y, size/2, order-1);
}