问测试一致性的基准问题

EN

#include <cstdlib> //for atoi
#include <iostream>
#include <iomanip> //for setw and setfill
#include <vector>

#include "bitmap_Image.h" //for saving the mandelbrot as a bmp

#include <pthread.h>

pthread_mutex_t mutexCounter;
int sharedCounter(0);
int percent(0);

int horizPixels(0);
int vertPixels(0);
int maxiter(0);

//doesn't need to be locked
std::vector<std::vector<int> > result; //create 2 dimensional vector

void *DoThread(void *null) {
    double curX,curY,xSquare,ySquare,x,y;
    int i, intx, inty, counter;
    counter = 0;

    do {
        counter++;
        pthread_mutex_lock (&mutexCounter); //lock
            intx = int((sharedCounter / vertPixels) + 0.5);
            inty = sharedCounter % vertPixels;
            sharedCounter++;
        pthread_mutex_unlock (&mutexCounter); //unlock

        //exit thread when finished
        if (intx >= horizPixels) {
            std::cout << "exited thread - I did " << counter << " calculations" << std::endl;
            pthread_exit((void*) 0);
        }

        //set x and y to the correct value now -> in the range like singlethread
        x = (3.0 / horizPixels) * (intx - (horizPixels / 1.5));
        y = (3.0 / vertPixels) * (inty - (vertPixels / 2));

        curX = x + x*x - y*y;
        curY = y + x*y + x*y;
        ySquare = curY*curY;
        xSquare = curX*curX;

        for (i=0; i<maxiter && ySquare + xSquare < 4;i++){
          ySquare = curY*curY;
          xSquare = curX*curX;
          curY = y + curX*curY + curX*curY;
          curX = x - ySquare + xSquare;
        }
        result[intx][inty] = i;
     } while (true);
}

int DoSingleThread(const double x, const double y) {
    double curX,curY,xSquare,ySquare;
    int i;

    curX = x + x*x - y*y;
    curY = y + x*y + x*y;
    ySquare = curY*curY;
    xSquare = curX*curX;

    for (i=0; i<maxiter && ySquare + xSquare < 4;i++){
      ySquare = curY*curY;
      xSquare = curX*curX;
      curY = y + curX*curY + curX*curY;
      curX = x - ySquare + xSquare;
    }
    return i;

}

void SingleThreaded(std::vector<std::vector<int> >&  result) {
    for(int x = horizPixels - 1; x != -1; x--) {
        for(int y = vertPixels - 1; y != -1; y--) {
            //3.0 -> so we always have -1.5 -> 1.5 as the window; (x - (horizPixels / 2) will go from -horizPixels/2 to +horizPixels/2
            result[x][y] = DoSingleThread((3.0 / horizPixels) * (x - (horizPixels / 1.5)),(3.0 / vertPixels) * (y - (vertPixels / 2)));
        }
    }
}

void MultiThreaded(int threadCount, std::vector<std::vector<int> >&  result) {
    /* Initialize and set thread detached attribute */
    pthread_t thread[threadCount];
    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);


    for (int i = 0; i < threadCount - 1; i++) {
        pthread_create(&thread[i], &attr, DoThread, NULL);
    }
    std::cout << "all threads created" << std::endl;

    for(int i = 0; i < threadCount - 1; i++) {
        pthread_join(thread[i], NULL);
    }
    std::cout << "all threads joined" << std::endl;
}

int main(int argc, char* argv[]) {
    //first arg = length along horizontal axis
    horizPixels = atoi(argv[1]);

    //second arg = length along vertical axis
    vertPixels = atoi(argv[2]);

    //third arg = iterations
    maxiter = atoi(argv[3]);

    //fourth arg = threads
    int threadCount = atoi(argv[4]);

    result = std::vector<std::vector<int> >(horizPixels, std::vector<int>(vertPixels,21)); // init 2-dimensional vector
    if (threadCount <= 1) {
        SingleThreaded(result);
    } else {
        MultiThreaded(threadCount, result);
    }


    //TODO: remove these lines
    bitmapImage image(horizPixels, vertPixels);
    for(int y = 0; y < vertPixels; y++) {
      for(int x = 0; x < horizPixels; x++) {
            image.setPixelRGB(x,y,16777216*result[x][y]/maxiter % 256, 65536*result[x][y]/maxiter % 256, 256*result[x][y]/maxiter % 256);
            //std::cout << std::setw(2) << std::setfill('0') << std::hex << result[x][y] << " ";
        }
        std::cout << std::endl;
    }

    image.saveToBitmapFile("~/Desktop/test.bmp",32);
}