bool_point_quadruple intersection_points (const Circle& c, [const bool verbose = false ])

Virtual const function 
Returns the intersection points of two Circles .
If the If the Circle t(origin, 5, 90); Circle c(origin, 3, 90); c.shift(3); c.rotate(0, 0, 45); bool_point_quadruple bpq = t.intersection_points(c); bpq.first.pt.dotlabel("$f$"); bpq.second.pt.dotlabel("$s$");
