e provides a number of facilities to ease interoperability with
      other C and C++ libraries including <a href="http://en.wikipedia.org/wiki/OpenGL" target="_top">OpenGL</a>,
      <a href="http://opencv.org/" target="_top">OpenCV</a>, <a href="http://eigen.tuxfamily.org" target="_top">Eigen</a>,
      <a href="http://qt-project.org/" target="_top">Qt</a>, and <a href="http://vtk.org/" target="_top">VTK</a>.
    </p>
<p>
      All of the interop headers are located in the <code class="computeroutput"><sp