rocessed point may be coplanar with an
horizon facet. Qhull creates a new facet without
a hyperplane. It links new facets for the same
horizon facet together. This is called a <em>samecycle</em>.
The new facet or samecycle is merged into the
horizon facet. </li>
</ul>
<ul>
<li><b>Concave facets. </b>A facet's centrum may be
above a neighboring facet. If so, the facets meet
at a concave angle. </li>
</ul>
<ul>
<li><b>Coplanar facets. </b>A facet's centrum may be
coplanar with a neighboring facet (i.e., it is