public Arc(VoronoiCell cell, Point p, Arc prev) : this(cell, p)
{
this.prev = prev;
}
public Arc(VoronoiCell cell, Point p, Arc prev, Arc next) : this(cell, p, prev)
{
this.next = next;
}
public Arc(VoronoiCell cell, Point p)
{
this.p = p;
this.cell = cell;
}