ee extra edges. These are interior edges that Geomview moves
towards the viewer (see 'lines closer' in Geomview's camera
options). Use option '<a href="qh-optg.html#Gt">Gt</a>' to make
the outer ridges transparent in 3-d. See <a
href="qh-eg.html#delaunay">Delaunay and Voronoi examples</a>.</p>

<p>For 2-d Delaunay triangulations, Mathematica ('<a
href="qh-opto.html#m">m</a>') and Maple ('<a
href="qh-optf.html#FM">FM</a>') output displays the lower facets of the corresponding convex
hull (a paraboloid). </p>