mandelbrot_slave.c

PVM下mandel_brot集并行化代码

/**
 * The mandelbrot set PVM source code.
 * Author:	Amal Cao
 * Since:	Dec. 18th 2008
 *  GPL v2.0
 */

#include <stdlib.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdio.h>
#include "pvm3.h"

#define ENCODING  PvmDataDefault
#define		X_RESN	800       /* x resolution */
#define		Y_RESN	800       /* y resolution */
#define  		H_MAX    360   /* HSB color space constant */
#define		DELAY   10	  /* delay factor: to make the program
                                    run slower and give more interesting
                                    timing result */

typedef struct complextype
{
        float real, imag;
} Compl;
	
int *val;

int main(void)
{
    int mytid;   /* my task id */
    int cc,ptid;
    
    int n = 0;
    int tmp[3];

    //double rsl_value=0.0;
    
    mytid = pvm_mytid();
    
    /* tell parent I am ready */
    ptid=pvm_parent();
    
    pvm_setopt(PvmRoute, PvmRouteDirect);
    pvm_initsend(ENCODING);
    pvm_send(ptid, 0);
    
    /* pack mytid in buffer */
    
    cc=pvm_recv(ptid,mytid);
    pvm_upkint(tmp,3,1);
    //rsl_value=flex(tmp[0],tmp[1]);
    
    int size = X_RESN/tmp[1];
    if (tmp[0] == tmp[1]-1)
    	size += X_RESN%tmp[1];
    int loop_step = tmp[2];
    int start = tmp[0]*X_RESN/tmp[1];
    
    val = (int *)malloc(size*Y_RESN*sizeof(int));
    
    int i, j, k;
    Compl z, c;
	float	lengthsq, temp;
     
    for(i=0; i < size; i++) {
        for(j=0; j < Y_RESN; j++) {

          z.real = z.imag = 0.0;
          c.real = ((float) j - 400.0)/200.0;               /* scale factors for 800 x 800 window */
	  c.imag = ((float)(i+start) - 400.0)/200.0;
          k = 0;

          do  {                                             /* iterate for pixel color */

            temp = z.real*z.real - z.imag*z.imag + c.real;
            z.imag = 2.0*z.real*z.imag + c.imag;
            z.real = temp;
            lengthsq = z.real*z.real+z.imag*z.imag;
            k++;

          } while (lengthsq < 4.0 && k < H_MAX * loop_step);
          val[i*X_RESN+j] = (k >= H_MAX * loop_step) ? H_MAX-1 : (k % H_MAX);

        }
    }
    
    pvm_initsend(ENCODING);
    pvm_pkint(val,size*Y_RESN,1);
    pvm_send(ptid,mytid);
    
    free(val);
    

}