title: FLTK filled polygon
body: <p>I am using <a href="http://www.fltk.org/index.php" rel="nofollow">FLTK</a> to create a GUI and I have to draw onto the screen some polygons (shapes).</p>
  
  <p>From their documentation of fl_complex_polygon:</p>
  
  <pre><code>Start and end drawing a convex filled polygon.
  </code></pre>
  
  <p>The problem? The polygon is not filled, but only the stroke is displayed. How can I make the polygon a filled shape?</p>
  
  <p>My code looks like this:</p>
  
  <pre><code>fl_color(FL_RED);
  fl_begin_complex_polygon();
  fl_line(mX,mY, x, y);
  ....
  fl_line(mX,mY, x, y);
  fl_end_complex_polygon();
  </code></pre>
  
  <p>Other related question: How can I redraw a <code>FL_BOX</code>? Do I have to draw a blank (background-colored) rectangle over it, or is there some <code>FL_BOX::clear()</code> function?</p>