[Paraview] render module interface documentation

[Doug McCorkle]

Hello,
     I am interested writing a render module for paraview 1.4. Is there any
documentation on the interface required for this module? I have read various
portions of the user's manual but can't seem to find what I am looking for.
Also, is there a doxygen site for all the paraview source similiar to vtk?
One last question, on the features page it mentions being able to describe
new filters in an XML format and the ability to write added functions for
the paraview interface, is there documentation somewhere for this
functionality? Thanks for the help.

Doug