/*!
\page free_faces_page Free faces
\n This mesh quality control highlights the faces connected to
less than two mesh volume elements. The free faces are shown with a
color different from the color of shared faces.
\image html free_faces.png
In this picture some volume mesh elements have been removed, as
a result some faces became connected only to one
volume. i.e. became free.
See Also a sample TUI Script of a
\ref tui_free_faces "Free Faces quality control" operation.
*/