Polygon Visible Face Selection: Selects faces that
are visible from the current point of view by drawing a
polygonal trap.
Tangency Face Selection: Selects faces by tangency
propagation from the last selected face.
Color Selection: Selects faces that are of the same
color as, and connected to the last selected face.
Belt Selection: Selects faces by propagation on a
belt. Select the first two faces to start the propagation.
Belt Selection Up to: Selects faces by propagation
on a belt, up to a given face. Select the first two faces
to start the propagation, and a third to stop it.