#include <stdio.h>
#include <stdlib.h>

#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glut.h>

void mydisplay(void);

void main(int argc, char **argv)
{
  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_SINGLE|GLUT_RGBA);
  glutCreateWindow (argv[0]);

  glutDisplayFunc(mydisplay);
  glutMainLoop();
}

void mydisplay(void)
{
  glClearColor(0.0, 0.0, 0.0, 0.0);
  glColor3f(1.0, 1.0, 1.0);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);

  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();

  glClear(GL_COLOR_BUFFER_BIT);

  glPushMatrix();

    glRotatef(13.0, 0.5, 0.2, 1.0);

    glBegin(GL_LINE_LOOP);

      glVertex2f(-0.5, -0.5);
      glVertex2f(-0.5,  0.5);
      glVertex2f( 0.5,  0.5);
      glVertex2f( 0.5, -0.5);

    glEnd();

  glPopMatrix();

  glFlush();
}