#include <iostream>
#include <opencv/cv.h>
#include <opencv/highgui.h>
#include <math.h>

int floatsign(double x, double y)
{
    double px = (0.5 + x * pow(2, -53));
    double py = (0.5 + y * pow(2, -53));
    double value = (12 - px)*(24 - py) - (12 - py)*(24 - px);

    if(value == 0)
        return 0;
    else if(value > 0)
        return 1;
    else if(value < 0)
        return -1;
}

int main(int argc, char** argv)
{
    IplImage* image = cvCreateImage(cvSize(256,256), IPL_DEPTH_8U, 3);

    for(int x = 0; x < 256; ++x)
    {
        for(int y = 0; y < 256; ++y)
        {
            int sign = floatsign(x, y);
            switch(sign)
            {
                case -1:
                    image->imageData[x*256*3 + y*3 + 0] = 255;
                    image->imageData[x*256*3 + y*3 + 1] = 0;
                    image->imageData[x*256*3 + y*3 + 2] = 0;
                    break;
                case 1:
                    image->imageData[x*256*3 + y*3 + 0] = 0;
                    image->imageData[x*256*3 + y*3 + 1] = 0;
                    image->imageData[x*256*3 + y*3 + 2] = 255;
                    break;
                case 0:
                    image->imageData[x*256*3 + y*3 + 0] = 0;
                    image->imageData[x*256*3 + y*3 + 1] = 255;
                    image->imageData[x*256*3 + y*3 + 2] = 255;
                    break;
            }
        }
    }
    cvFlip(image, image, 0);
    std::cout<<"write"<<std::endl;
    cvSaveImage("image.png", image);
    return 0;
}