[Paraview] Problem using Generate Surface Normals

[Adriano Gagliardi]

Dear All,

I have a custom reader that works fine and loads mesh and data in as I
require. However, when I try to execute 'Generate Surface Normals' on it, I
get the error below. The process I am following is:

-> Read in mesh and data(multi-block data-set, vtkUnstructuredGrid stored in
each block)
-> Extract blocks
-> Extract surface (outputs vtkPolyData)
-> Generate Surface Normals 
-> Error message

ERROR: In /usr/Paraview/ParaView3/VTK/Filtering/vtkExecutive.cxx, line 757
vtkCompositeDataPipeline (0x8135e40): Algorithm vtkTestReader(0x7ecf280)
returned failure for request: vtkInformation (0x1c9cf730)
  Debug: Off
  Modified Time: 369530
  Reference Count: 1
  Registered Events: (none)
  Request: REQUEST_DATA
  FORWARD_DIRECTION: 0
  ALGORITHM_AFTER_FORWARD: 1
  FROM_OUTPUT_PORT: 0

Notably, after this happens the data in the entire pipeline is messed up.
Can someone point me to something that may be missing in my reader?

Best regards,

Adriano

===================================

Adriano Gagliardi MEng PhD
Project Scientist
Computational Aerodynamics
Aircraft Research Association Ltd.
Manton Lane
Bedford

Tel: 01234 32 4644
E-mail: agagliardi at ara.co.uk
Url: www.ara.co.uk 


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