title: Eigen, rotate a vector3d with a quaternion?
body: <p>I have an array of  3D points, as an <code>std::vector&lt;Eigen::Vector3d&gt;</code>.</p>
  <p>I need to transform these points with a position and quaternion.</p>
  <p>My questions are:</p>
  <p>How can I rotate these points with a quaternion? And is there a faster way than:</p>
  <pre><code>    Eigen::Vector3d Trans; // position to move by
      Eigen::Quaterniond quats;  // quat to rotate by
  
  for (int p = 0; p &lt; objectPoints.size(); p++)
          {
              Eigen::Vector3d pnt;
              //add pose
              pnt.x = objectPointsTri[p].x + -Trans.x();
              pnt.y = objectPointsTri[p].y + -Trans.y();
              pnt.z = objectPointsTri[p].z + -Trans.z();
  
              Eigen::Vector3d pntRot = // rotate pnt by the quaternion
  
  
  
          }
  </code></pre>