Creates segments on the
convex hull of the triangulation.
If you are triangulating a vertex set, this switch causes a
.poly file to
be written, containing all edges in the convex hull.
If you are triangulating a PSLG,
this switch specifies that the whole convex hull of the PSLG should
be triangulated, regardless of what segments the PSLG has. If you do not
use this switch when triangulating a PSLG, it is assumed that you
have identified the region to be triangulated by surrounding it
with segments of the input PSLG.
Beware: if you are not careful, this switch can cause the
introduction of an extremely thin angle
between a PSLG segment and a convex hull segment, which can cause
overrefinement.
If you are refining a mesh, this switch works
differently; it generates the set of boundary edges of the mesh,
including boundaries of holes.
(This is useful if no .poly file was read.)