title: Draw text in QGLWidget when using raw OpenGL
body: <p>I am writing Qt app that wraps an external 3D engine.I use QGLWidget to encapsulate the engine API.I don't use any Qt GL API methods though I do create GL context using Qt API:</p>
  
  <pre><code>QGLFormat format;
  format.setProfile(QGLFormat::CompatibilityProfile);
  format.setVersion(4,2);
  format.setDoubleBuffer(true);
  format.setSwapInterval(1);
  </code></pre>
  
  <p>Now,I was searching for a way to draw text in the viewport and found Qt's <a href="http://doc.qt.digia.com/4.1/qglwidget.html" rel="nofollow">rendeText()</a>.</p>
  
  <p>I have tried to use it but no text is begin drawn.
  That is how I do it:</p>
  
  <pre><code>    qglColor(Qt::black);
      this-&gt;renderText(50, 50, "Some text");
  </code></pre>
  
  <p>What do I miss here?</p>
  
  <p>Btw, my depth buffer is off.</p>