Export arrow(seg_idx, t) (#17)

* add arrow

* update

* update headers

Author: district10

headers

@@ -249,6 +249,7 @@ struct PolylineRuler
     const RowVectors &polyline() const { return polyline_; }
     int N() const { return N_; }
     bool is_wgs84() const { return is_wgs84_; }
+    Eigen::Vector3d k() const { return k_; }
 
     static Eigen::VectorXd ranges(const Eigen::Ref<const RowVectors> &polyline,
                                   bool is_wgs84 = false)
@@ -407,6 +408,12 @@ struct PolylineRuler
                            t, is_wgs84_);
     }
 
+    std::pair<Eigen::Vector3d, Eigen::Vector3d> arrow(int seg_idx,
+                                                      double t) const
+    {
+        return std::make_pair(at(seg_idx, t), dir(seg_idx));
+    }
+
     std::pair<Eigen::Vector3d, Eigen::Vector3d>
     arrow(double range, bool smooth_joint = true) const
     {

src/polyline_ruler.hpp

@@ -79,6 +79,7 @@ CUBAO_INLINE void bind_polyline_ruler(py::module &m)
         .def("polyline", &PolylineRuler::polyline, rvp::reference_internal)
         .def("N", &PolylineRuler::N)
         .def("is_wgs84", &PolylineRuler::is_wgs84)
+        .def("k", &PolylineRuler::k)
         //
         .def_static(
             "_ranges",
@@ -119,7 +120,12 @@ CUBAO_INLINE void bind_polyline_ruler(py::module &m)
         .def("at",
              py::overload_cast<int, double>(&PolylineRuler::at, py::const_),
              py::kw_only(), "segment_index"_a, "t"_a)
-        .def("arrow", &PolylineRuler::arrow, "range"_a, //
+        .def("arrow",
+             py::overload_cast<int, double>(&PolylineRuler::arrow, py::const_),
+             py::kw_only(), "index"_a, "t"_a)
+        .def("arrow",
+             py::overload_cast<double, bool>(&PolylineRuler::arrow, py::const_),
+             "range"_a, //
              py::kw_only(), "smooth_joint"_a = true)
         .def("arrows",
              py::overload_cast<const Eigen::Ref<const Eigen::VectorXd> &, bool>(

src/pybind11_polyline_ruler.hpp

@@ -305,6 +305,10 @@ def test_polyline_ruler():
     assert np.all(xyz == [101, 10, 0])
     assert np.all(dir == [1, 0, 0])
 
+    xyz, dir = ruler.arrow(index=0, t=0.2)
+    assert np.all(xyz == [2, 0, 0])
+    assert np.all(dir == [1, 0, 0])
+
     ranges, xyzs, dirs = ruler.arrows([-1, 10, 111])
     assert len(ranges) == len(xyzs) == len(dirs)
     ranges, xyzs, dirs = ruler.arrows(10.0)