title: QT X11 and OpenGL
body: <ol>
  <li>How can I build Qt for X11 with OpenGL support?
  I have Hardware acceleration on my device(GPU), but when I config the qt(qml) application to work with opengl I can’t see any improvment with the performance… it become more slower performance.</li>
  </ol>
  
  <p>I use the command: 
  <code>QApplication::setGraphicsSystem("opengl");</code></p>
  
  <p>I use Qt lighthouse(not qt embedded-linux).</p>
  
  <ol>
  <li>How can I ensure that the Qt is really use the gpu acceleration to paint qt/qml widgets on the screen?</li>
  </ol>