### Description
This example demonstrates how to read an unstructured grid (VTU) file. The front facing faces are colored white, while the back facing faces are colored red.

An example data file (.vtu) for testing can be found in [VTKExamples/src/TestingData/tetra.vtu](https://raw.githubusercontent.com/lorensen/VTKExamples/master/src/Testing/Data/tetra.vtu).

