title: Render RGB-D image from mesh
body: <p>I have a mesh model (.ply file) and I have rendered it with VTK and changed the camera viewpoint. </p>
  
  <p>From the new camera viewpoint how can I render an RGB and a depth image? I think this might be raytracing, but not sure</p>
  
  <p><strong>EDIT</strong> </p>
  
  <p>I want to generate a real depth map, as opposed to just a visualization of the depth. The visualization can be achieved by using values in Z buffer and scaling between 0-255 but this does not provide real depth information.</p>