/*
   compilation command:

   g++ -std=c++11 -Wall -o gdk-pixbuf-demo `pkg-config --cflags --libs gdk-pixbuf-2.0` gdk-pixbuf-demo.cpp
*/

#include <gdk-pixbuf/gdk-pixbuf.h>

int main() {
   unsigned int width = 96; unsigned int height = 96;
   GdkPixbuf* pixbuf = gdk_pixbuf_new(GDK_COLORSPACE_RGB, FALSE, 8,
      width, height);
   int n_channels = gdk_pixbuf_get_n_channels(pixbuf);
   int rowstride = gdk_pixbuf_get_rowstride(pixbuf);
   guchar* pixels = gdk_pixbuf_get_pixels(pixbuf);
   for (unsigned int i = 0; i < height; ++i) {
      for (unsigned int j = 0; j < width; ++j) {
	 guchar* pp = pixels + i * rowstride + j * n_channels;
	 if ((i / (height/8) + j / (width/8)) % 2 == 0) {
	    pp[0] = 25; /* red */
	    pp[1] = 7; /* green */
	    pp[2] = 26; /* blue */
	 } else {
	    pp[0] = 248; /* red */
	    pp[1] = 201; /* green */
	    pp[2] = 95; /* blue */
	 }
      }
   }
   gdk_pixbuf_save(pixbuf, "output.jpg", "jpeg",
      nullptr, "quality", "100", nullptr);
}