#include <stdio.h>

  #define STB_IMAGE_WRITE_IMPLEMENTATION
  #include "stb_image_write.h"

  #define STB_IMAGE_IMPLEMENTATION
  #include "stb_image.h"

  int main(int argc, char** argv)
  {
     int w, h, n;

    //rgba
    //load image
    unsigned char *data = stbi_load("rgba.png", &w, &h, &n, 0);

    printf("%d, %d, %d\n", w, h, n);

    //change pixel

    //rgba,write 10 red pixel at line 11
    for (int dx = 0; dx < 10; ++dx)
    {
        data[n * w * 10 + dx * n + 0] = 255;
        data[n * w * 10 + dx * n + 1] = 0;
        data[n * w * 10 + dx * n + 2] = 0;
        data[n * w * 10 + dx * n + 3] = 255;
    }
    

    //write image
    stbi_write_png("write.png", w, h, n, data, w * 4);

    stbi_image_free(data);


    return 0;
  }