Computer Graphics: Fractals generation using Mandelbrot Set with C/C++ in Code::Blocks

Computer Graphics: Fractals generation using Mandelbrot Set with C/C++ in Code::Blocks - tutorial advance

“Clouds are not spheres, mountains are not cones, coastlines are not circles, and bark is not smooth, nor does lightning travel in a straight line.” – Benoit Mandelbrot
The Mandelbrot set is created by a general technique where a function of the form
z_n+1 = f(z_n)
is used to create a series of a complex variable. In the case of the Mandelbrot, the function is
f(z_n) = z_n² + z_o
This series is generated for every initial point z_o on some partition of the complex plane separating the complex plane into two categories:

Points inside the Mandelbrot set
Points outside the Mandelbrot set

Source Code :

 #include <windows.h> #include <stdio.h> #include <math.h> #define ROUND(a) ((int) (a + 0.5))  /* set window handle */ static HWND sHwnd; COLORREF color;  typedef struct {     float x, y; } Complex;  void SetWindowHandle(HWND hwnd){     sHwnd=hwnd; }  void setPixel(int x,int y,COLORREF color){     if(sHwnd==NULL){         MessageBox(NULL,"sHwnd was not initialized !","Error",MB_OK|MB_ICONERROR);         exit(0);     }     HDC hdc=GetDC(sHwnd);     SetPixel(hdc,x,y,color);     ReleaseDC(sHwnd,hdc);     return; }  Complex complexSquare(Complex c){     Complex cSq;      cSq.x = c.x * c.x - c.y * c.y;     cSq.y = 2 * c.x * c.y;     return cSq; }  int iterate (Complex zInit, int maxIter){     Complex z = zInit;     int cnt = 0;      while((z.x * z.x + z.y * z.y <= 4)&& (cnt < maxIter)){         z = complexSquare(z);         z.x += zInit.x;         z.y += zInit.y;         cnt++;     }     return cnt; } void madelbrot(int nx, int ny, int maxIter, float realMin, float realMax, float imagMin, float imagMax){     float realInc = (realMax - realMin) / nx;     float imagInc = (imagMax - imagMin) / ny;     Complex z;     int x, y;     int cnt;     for(x = 0, z.x = realMin; x < nx; x++, z.x += realInc)        for(y = 0, z.y = imagMin; y < ny; y++, z.y += imagInc ){             cnt = iterate(z, maxIter);             if(cnt == maxIter)                 color = RGB(255, 0, 0);             else{                 color = RGB(0, cnt, 0);              }             setPixel(x, y, color);        } } /* Window Procedure WndProc */ LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam){     switch(message){         case WM_PAINT:             SetWindowHandle(hwnd);             madelbrot(750, 500, 500, -2.4,0.8,-1.4 ,1.4);             break;         case WM_CLOSE: // FAIL THROUGH to call DefWindowProc             break;         case WM_DESTROY:             PostQuitMessage(0);             return 0;         default:         break; // FAIL to call DefWindowProc //     }     return DefWindowProc(hwnd,message,wParam,lParam); } int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int iCmdShow){     static TCHAR szAppName[] = TEXT("Fractals");     WNDCLASS wndclass;     wndclass.style         = CS_HREDRAW|CS_VREDRAW ;     wndclass.lpfnWndProc   = WndProc ;     wndclass.cbClsExtra    = 0 ;     wndclass.cbWndExtra    = 0 ;     wndclass.hInstance     = hInstance ;     wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION) ;     wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;     wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;     wndclass.lpszMenuName  = NULL ;     wndclass.lpszClassName = szAppName ;     // Register the window //     if(!RegisterClass(&wndclass)){         MessageBox(NULL,"Registering the class failled","Error",MB_OK|MB_ICONERROR);         exit(0);     }     // Createw indow //     HWND hwnd=CreateWindow(szAppName,"Mandelbrot Fractal - Programming Techniques",                 WS_OVERLAPPEDWINDOW,                  CW_USEDEFAULT,                  CW_USEDEFAULT,                  CW_USEDEFAULT,                  CW_USEDEFAULT,                  NULL,                  NULL,                  hInstance,                  NULL);     if(!hwnd){         MessageBox(NULL,"Window Creation Failed!","Error",MB_OK);         exit(0);     }     // ShowWindow and UpdateWindow //     ShowWindow(hwnd,iCmdShow);     UpdateWindow(hwnd);     // Message Loop //     MSG msg;     while(GetMessage(&msg,NULL,0,0)){         TranslateMessage(&msg);         DispatchMessage(&msg);     }     /* return no error to the operating system */     return 0; }

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#include <windows.h>

#include <stdio.h>

#include <math.h>

#define ROUND(a) ((int) (a + 0.5))

/* set window handle */

static HWND sHwnd;

COLORREF color;

typedef struct {

float x, y;

} Complex;

void SetWindowHandle(HWND hwnd){

sHwnd=hwnd;

}

void setPixel(int x,int y,COLORREF color){

if(sHwnd==NULL){

MessageBox(NULL,"sHwnd was not initialized !","Error",MB_OK|MB_ICONERROR);

exit(0);

}

HDC hdc=GetDC(sHwnd);

SetPixel(hdc,x,y,color);

ReleaseDC(sHwnd,hdc);

return;

}

Complex complexSquare(Complex c){

Complex cSq;

cSq.x = c.x * c.x - c.y * c.y;

cSq.y = 2 * c.x * c.y;

return cSq;

}

int iterate (Complex zInit, int maxIter){

Complex z = zInit;

int cnt = 0;

while((z.x * z.x + z.y * z.y <= 4)&& (cnt < maxIter)){

z = complexSquare(z);

z.x += zInit.x;

z.y += zInit.y;

cnt++;

}

return cnt;

}

void madelbrot(int nx, int ny, int maxIter, float realMin, float realMax, float imagMin, float imagMax){

float realInc = (realMax - realMin) / nx;

float imagInc = (imagMax - imagMin) / ny;

Complex z;

int x, y;

int cnt;

for(x = 0, z.x = realMin; x < nx; x++, z.x += realInc)

for(y = 0, z.y = imagMin; y < ny; y++, z.y += imagInc ){

cnt = iterate(z, maxIter);

if(cnt == maxIter)

color = RGB(255, 0, 0);

else{

color = RGB(0, cnt, 0);

}

setPixel(x, y, color);

}

/* Window Procedure WndProc */

LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam){

switch(message){

case WM_PAINT:

SetWindowHandle(hwnd);

madelbrot(750, 500, 500, -2.4,0.8,-1.4 ,1.4);

break;

case WM_CLOSE: // FAIL THROUGH to call DefWindowProc

break;

case WM_DESTROY:

PostQuitMessage(0);

return 0;

default:

break; // FAIL to call DefWindowProc //

}

return DefWindowProc(hwnd,message,wParam,lParam);

}

int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int iCmdShow){

static TCHAR szAppName[] = TEXT("Fractals");

WNDCLASS wndclass;

wndclass.style = CS_HREDRAW|CS_VREDRAW ;

wndclass.lpfnWndProc = WndProc ;

wndclass.cbClsExtra = 0 ;

wndclass.cbWndExtra = 0 ;

wndclass.hInstance = hInstance ;

wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;

wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;

wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;

wndclass.lpszMenuName = NULL ;

wndclass.lpszClassName = szAppName ;

// Register the window //

if(!RegisterClass(&wndclass)){

MessageBox(NULL,"Registering the class failled","Error",MB_OK|MB_ICONERROR);

exit(0);

}

// Createw indow //

HWND hwnd=CreateWindow(szAppName,"Mandelbrot Fractal - Programming Techniques",

WS_OVERLAPPEDWINDOW,

CW_USEDEFAULT,

NULL,

hInstance,

NULL);

if(!hwnd){

MessageBox(NULL,"Window Creation Failed!","Error",MB_OK);

exit(0);

}

// ShowWindow and UpdateWindow //

ShowWindow(hwnd,iCmdShow);

UpdateWindow(hwnd);

// Message Loop //

MSG msg;

while(GetMessage(&msg,NULL,0,0)){

TranslateMessage(&msg);

DispatchMessage(&msg);

}

/* return no error to the operating system */

return 0;

}

Output

 <a href="http://lh5.ggpht.com/-jhvgSQpawZg/T1zNGEe8vsI/AAAAAAAAASU/QU37ocmJvpw/s1600-h/Mandelbrot%252520Set%25255B4%25255D.jpg"><img style="display: inline; border-width: 0px;" title="Mandelbrot Set" src="http://lh4.ggpht.com/-GoSyQm15LN0/T1zNHrOVhjI/AAAAAAAAASc/vOXy0WDW0NU/Mandelbrot%252520Set_thumb%25255B2%25255D.jpg?imgmax=800" alt="Mandelbrot Set" width="454" height="333" border="0" /></a>