Node:Tetrahedron Getstart, Next:Dodecahedron Getstart, Previous:Polyhedron Getstart, Up:Polyhedron Getstart

The center of a tetrahedron is the intersection of the lines from a
vertex to the center of the opposite side. At least, in 3DLDF, this is
the `center`

of a `Tetrahedron`

. I'm not 100 degrees
certain
that this is mathematically correct.

Tetrahedron t(origin, 4); t.draw(); t.get_center().dotlabel("$c$");

Fig. 39.