title: Make openGL lines connected
body: <p>Right now I'v created a polygon, then I do the same thing but with line_loop to draw the outline.  My issue right now is if I set the line thickness to high, the lines arn't connected. Their ends would need to be (linewidth) longer... is there a way to fix this?</p>
  
  <p>Thanks</p>
  
  <pre><code>glMatrixMode (GL_PROJECTION);
          glLoadIdentity ();
          glOrtho (0, 600, 600, 0, 0, 1);
          glMatrixMode (GL_MODELVIEW);
  ......
  glLineWidth(5.0);
  glTranslatef(250,250,0);
  glRotated(x,0,0,50.0);
      glBegin(GL_POLYGON); //Begin quadrilateral coordinates
      //Trapezoid
      glColor3f(255,0,0);
  glVertex2f(0,0);
  glVertex2f(100,0);
  glVertex2f(100,100);
  glVertex2f(50,50);
  glVertex2f(0,100);
  
      glEnd(); //End quadrilateral coordinates
  
      glBegin(GL_LINE_LOOP); //Begin quadrilateral coordinates
  
      //Trapezoid
      glColor3f(0,255,0);
      glVertex2f(0,0);
      glVertex2f(100,0);
      glVertex2f(100,100);
      glVertex2f(50,50);
      glVertex2f(0,100);
  
      glEnd(); //End quadrilateral coordinates
  </code></pre>