The documentation is fairly confusing and I know that I need to keep track of the actual grid location of my data. Writing a python script to convert binary data into this vtk format. I want to leave the legacy VTK behind so that I can utilize the parallelism that XML will give. Any help here is appreciated.
I recently came across a Python tool that claims to convert between all kinds of different mesh formats. I haven't gotten around to trying it yet, but maybe it can help you:
I don't think there is a good argument to write a converter -- whatever it produces has the same information content as the existing VTK files you already have, and the usual visualization programs can visualize them just fine.
But there is a good case to be made for re-writing the code you have that produces VTK files. I agree that the VTU file is confusing and poorly documented, but take a look at some VTU files that you can find on the web. As an example, there are numerous VTU files in subdirectories here: https://github.com/geodynamics/aspect/tree/master/tests (you may just want to check out the entire git repository to look for them). You can also look at code that writes VTU files -- e.g., the
write_vtu() function here: https://github.com/dealii/dealii/blob/master/source/base/data_out_base.cc