I agree with John. See VTK/Parallel/vtkVPICReader.cxx for an example.
David E DeMarle Kitware, Inc. R&D Engineer 21 Corporate Drive Clifton Park, NY 12065-8662 Phone: 518-881-4909 On Mon, Mar 5, 2012 at 2:34 PM, Biddiscombe, John A. <[email protected]> wrote: > Erik, > > I'd try 3, but instead of using sub extents (which I might have misunderstood > what that implies), I'd use the TableExtentTranslator so that each piece is > mapped to the already computed extents that you saved your data using. > > Essentially, you already have a mapping between pieces and extents, you can > set these up in the TableExtentTranslator and then when the downstream code > requests extents, they'll be calculated based on the values you've setup. > Even though the pipeline requests a structured VTK_3D_EXTENT from your > reader, the values in that Extent are calculated based on the mpi rank (piece > number), so by fooling it with a custom extent translator, all should work > (note that I say should, because I've used my own custom extent translator, > but not the table extent trans so I'm guessing - when Dave DeM reads this > he'll either put us right, or possibly concur). > > JB > > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Erik Wilson > Sent: 05 March 2012 17:22 > To: [email protected] > Subject: [Paraview] Multipiece Structured Dataset questions > > > Hello all, > > I am attempting to develop a Paraview plugin to read in parallel a multipiece > structured dataset through a custom I/O library. Since our data is already > broken up into pieces it would be nice to use a grid type which has a > DATA_EXTENT_TYPE of VTK_PIECES_EXTENT, otherwise when using VTK_3D_EXTENT > extra code will need to be created to calculate and subtract sub-extents such > as seen in vtkXMLPStructuredDataReader. There are three different options I > am considering for developing this reader: > > 1) Use an Unstructured Grid > > Simply translate our structured grid into a vtkUnstructuredGrid using > Hexahedron cells. Will unstructured grids be as efficient as structured grids > for operations such as cut planes and streamlines, or are there any > efficiency disadvantages to using unstructured grids in general? > > 2) Subclass Structured Grid > > Create a subclass of vtkStructuredGrid which uses has a DATA_EXTENT_TYPE of > VTK_PIECES_EXTENT. Is this even feasible, or any other issues? > > 3) Use a Structured Grid > > Just write the code to calculate and subtract 3d sub-extents, better than > above options? > > > Any feedback or advice is greatly appreciated. > > Thanks, > -Erik > > _______________________________________________ > Powered by www.kitware.com > > Visit other Kitware open-source projects at > http://www.kitware.com/opensource/opensource.html > > Please keep messages on-topic and check the ParaView Wiki at: > http://paraview.org/Wiki/ParaView > > Follow this link to subscribe/unsubscribe: > http://www.paraview.org/mailman/listinfo/paraview > _______________________________________________ > Powered by www.kitware.com > > Visit other Kitware open-source projects at > http://www.kitware.com/opensource/opensource.html > > Please keep messages on-topic and check the ParaView Wiki at: > http://paraview.org/Wiki/ParaView > > Follow this link to subscribe/unsubscribe: > http://www.paraview.org/mailman/listinfo/paraview _______________________________________________ Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview
