[Paraview] Open vtk with zlib

[Brad King]

Sébastien Blaise wrote:
> ERROR: In 
> /build/buildd/paraview-3.2.2/VTK/IO/vtkXMLUnstructuredDataReader.cxx, 
> line 515
> vtkXMLUnstructuredGridReader (0xa030228): Cannot read points array from 
> Points in piece 0. The data array in the element may be too short.

Note that the error occurs when reading the Points array, not your data array.
The problem is here:

<Points>
  <DataArray type="Float64" NumberOfComponents="3" format="appended" offset="16420"/>
</Points>

The offset needs to point at the offset from '_' to the beginning of the
compression header for the Points array.  The offset you give is the
uncompressed size, but it should account for the compressed size of the
array before it.

Note that files written by VTK have extra whitespace after the offset field
because they actually reserve space to seek back and set it *after* writing
earlier arrays to the AppendedData section.

-Brad