Made point and dpoint constructable from each other.

tools/python/src/vector.cpp

@@ -181,6 +181,7 @@ void bind_vector(py::module& m)
     typedef point type;
     py::class_<type>(m, "point", "This object represents a single point of integer coordinates that maps directly to a dlib::point.")
             .def(py::init<long,long>(), py::arg("x"), py::arg("y"))
+            .def(py::init<dpoint>(), py::arg("p"))
             .def("__repr__", &point__repr__)
             .def("__str__", &point__str__)
             .def_property("x", &point_x, [](point& p, long x){p.x()=x;}, "The x-coordinate of the point.")
@@ -200,6 +201,7 @@ void bind_vector(py::module& m)
     typedef dpoint type;
     py::class_<type>(m, "dpoint", "This object represents a single point of floating point coordinates that maps directly to a dlib::dpoint.")
             .def(py::init<double,double>(), py::arg("x"), py::arg("y"))
+            .def(py::init<point>(), py::arg("p"))
             .def("__repr__", &dpoint__repr__)
             .def("__str__", &dpoint__str__)
             .def_property("x", &dpoint_x, [](dpoint& p, double x){p.x()=x;}, "The x-coordinate of the dpoint.")