function &del(Vertex &$v)
{
// $p <-> $v <-> $n Will delete $v and $ns
// $ps $ns
$p = $v->Prev();
// Get ref to previous vertex
$n = $v->Next();
// Get ref to next vertex
$p->setNext($n);
// Link previous forward to next
$n->setPrev($p);
// Link next back to previous
// Segments
$ps = $p->Nseg();
// Get ref to previous segment
$ns = $v->Nseg();
// Get ref to next segment
$n->setPseg($ps);
// Link next back to previous segment
$ns = NULL;
$v = NULL;
// Free the memory
$this->cnt--;
// One less vertex
return $n;
// Return a ref to the next valid vertex
}
