#include "include/glut.h"
#include <iostream>

void MyDrawFunction();

int main(int argc, char** argv)
{
     glutInit(&argc, argv);
     glutInitWindowSize(640, 480);
     glutInitWindowPosition(10, 10);
     glutCreateWindow("My OpenGL application");
    
     glClearColor(1.0, 1.0, 1.0, 0.0);
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
     gluOrtho2D(0.0, 640.0, 0.0, 480.0);

     glutDisplayFunc(MyDrawFunction);

     glutMainLoop();
     return 0;
}

void MyDrawFunction()
{
     glClear(GL_COLOR_BUFFER_BIT);
     glColor3f(1.0, 0.0, 0.0);
     glPointSize(2.0);

     // green color
     glColor3ub(0, 255, 0);

     // draw line (by pixel)
     for (int i = 100; i < 300; i++)
     {
          glBegin(GL_POINTS);
          glVertex2i(i, i); // x=i, y=i
          glEnd();
     }

     glFlush();
}