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C/C++ Quellcode

/*
*   File: MANDEL.C
*
*        Mandelbrot set generator.
*        Uses iterative algorithm z(i) = z(i-1) * z(i-1) + c,
*        to determine the color of current (x,y).
*
*             DO NOT try to compile this using WCL386 !
*                Use "WCL -3" or Borland/C++ instead.
*
*                (c) Lenik Terenin, 1995
*/
    #include <stdio.h>
    #include <conio.h>
//    #include
 
    #define LIMIT 100        // Increase LIMIT to get more exact picture
 
    #ifdef __BORLANDC__
        void SetVmode( short mode )
        {
            asm {
                mov        ax, [mode]
                push        bp
                int        10h
                pop        bp
            }
        }
 
        #define PutPixel13(x,y,c) pokeb( 0xA000, (x) + (y) * 320, (c))
    #else
        #ifdef __386__
            #error Can't run in 32-bit mode, sorry...
        #endif
 
        void SetVmode(short);
        #pragma aux SetVmode =        \
            "push        bp"        \
            "int        10h"        \
            "pop        bp"        \
        parm [ax]
 
        void PutPixel13( short x, short y, short c);
        #pragma aux PutPixel13 = \
            "push ax"        \
            "mov ax, 0a000h"        \
            "mov es, ax"\
            "pop ax"        \
            "shl bx,6"        \
            "add di,bx"        \
            "shl bx,2"        \
            "add di,bx"        \
            "stosb"        \
        parm [di] [bx] [ax] modify [es] nomemory
    #endif
 
    int main()
    {
        int i, j, k;
        double z_i, z_r, c_i, c_r, tmp;
        double module;
 
        SetVmode( 0x13 );
 
        for( i=-160; i<160; i++) {
            c_i = ((double) i) / 100.0;
            for( j=-160; j<40; j++) {
                c_r = ((double) j) / 80.0;
                z_i = z_r = 0.0;
                for( k=0; k<LIMIT; k++) {
                    tmp = z_r * z_r - z_i * z_i;
 
                    z_i = 2 * z_r * z_i + c_i;      // z = z * z + c
                    z_r = tmp                + c_r;
 
                    module = z_r * z_r + z_i * z_i; // is |z| large enough?
                    if( module > 1.0E16 ) break;
                }
                if( k<LIMIT) {
                    PutPixel13( i+160, j+160, (k/15)*2+20);
                }
                else PutPixel13( i+160, j+160, 16);
            }
            if( kbhit() ) break;
        }
 
        getch();        
        SetVmode(3);
 
        return 0;
    }