[Paraview] Displaying VTK non-linear cell types

[David C Thompson]

> I was trying to display VTK  non-linear cells. ...
> When I use the wireframe of surface for display, I get the triangles
> instead of single quadrilateral. Is it not possible to display such
> non-linear cells in paraview? I would appreciate your help. 
Triangles are rendered because that is what the OpenGL graphics library
(and most other interactive rendering libraries) can accept as a
rendering primitive. If the triangles don't approximate the
nonlinearities in the cell very well, you can refine the approximation
using the "Tessellate" filter in ParaView. If you choose to do this, you
may want to run "Clean to Grid" afterwards as it will help with
rendering speed.

	David