Configuring Server Environment Using *.pvx XML Files

When running pvserver/pvdataserver or pvrenderserver on a cluster, users may want to configure some environment variables eg. DISPLAY in case of multi-headed nodes for the processes. This can be done using the PVX configuration XML file.

Where to specify this?

• pvx file can be specified as the last command line argument for any of the server processes.
• Typically the pvx file is specified for all the executables whose environment is being changed using the pvx file. In case of data-server/render-server configuration, if you are setting up the environment for the two processes groups, then the pvx file must be passed as a command line option to both the executables: pvdataserver and pvrenderserver.
• When running in parallel the file is read on all nodes, hence must be present on all nodes.

Structure

<?xml version="1.0" ?>
<pvx>
  <Process Type="server|dataserver|renderserver">
    <!-- 
      The only supported Type values are "server", "dataserver" or "renderserver".
      This controls which executable this configuration is applicable to.
      There can be multiple <Process /> elements in the same pvx file.
      ------------------------------------------------------
      |  Executable     | Applicable Process Type          |
      |  pvserver       | server, dataserver, renderserver |
      |  pvrenderserver | server, renderserver             |
      |  pvdataserver   | server, dataserver               |
      ------------------------------------------------------
     -->
    <Machine name="hostname"
             Environment="DISPLAY=m1:0"
             LowerLeft="-1.0 -1.0 -1.0"
             LowerRight="1.0 -1.0 -1.0"
             UpperLeft="-1.0  1.0 -1.0">
      <!--
         There can be multiple <Machine> elements in a <Process> element, 
         each one identifying the configuration for a process. 
         All attributes are optional.
         name="hostname"
         Environment: the environment for the process.
         LowerLeft|LowerRight|UpperLeft : CAVE configuration parameters applicable
                                          for versions 3.8 or latter only.
 
       -->
    </Machine>
  </Process>
</pvx>

• Only 2 vectors ([LowerRight - LowerLef] and [UpperLeft - LowerLeft]) are needed, the third vector is computed from these 2.

Cave Rendering

Instructions

• Turn on PARAVIEW_USE_MPI and PARAVIEW_USE_ICE_T
• run the servers using the pvx file: mpiexec -np 2 pvserver cave.pvx
• start and connect a client

Notes

• See below for an example of a cave configuration file

<?xml version="1.0" ?>
<pvx>
 <Process Type="client" />
 <Process Type="server">
  <!-- 2 render windows will be created on the machine Erna: 
       the first rendering has a camera looking forward,
       the second rendering has a camera looking backward -->
  <Machine Name="Erna"
           Environment="DISPLAY=:0"
           FullScreen="0" <!-- since version v3.98.0-201-g1ae250c -->
           ShowBorders="0" <!-- since version v3.98.0-201-g1ae250c -->
           Geometry="1024x768+0+0" <!-- since version v3.98.0-123-ge32eeed -->
           <!-- Camera looks forward:
                 dx = 2, dy = 2, dz = -2
                 Z = -2 defines the view angle  -->
           LowerLeft="-1 -1 -2"
           LowerRight="1 -1 -2"
           UpperLeft="-1  1 -2" />
  <Machine Name="Erna"
           Environment="DISPLAY=:0"
           <!-- Camera looks backward:
                 dx = -2, dy = 2, dz = 2
                 Z = 2 defines the distance from the camera to the view plane  -->
           LowerLeft="1 -1 2"
           LowerRight="-1 -1 2"
           UpperLeft="1  1 2" />
  </Process>
</pvx>

• See vtkCaveRenderManager::ComputeCamera for more information on how the coordinates are used to configure the cameras
• The rendering on the server is full screen by default. If you want the windows to be smaller for debugging, set the environment variable PV_ICET_WINDOW_BORDERS=1 on the client machine.

Related Pages

• Immersive_ParaView