either should be or should not be constructed, depending on the
value of the previous parameter (<b>Specified Faces/Edges are</b>).
Faces (or edges) can be selected either in the Object Browser or in
- the VTK Viewer.
+ the VTK Viewer. \b Add button becomes active as soon as a suitable
+ sub-shape is selected.
\note A mesh shown in the 3D Viewer can prevent selection of faces
and edges, just hide the mesh to avoid this. If a face, which should be
selected, is hidden by other faces, consider creating a
