Implement iDynTree base type type_caster for pybind11 bindings

CHANGELOG.md

@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - Added the possibility to draw in different portions of the visualizer window and textures at the same time. Allow disabling the drawing on textures (https://github.com/robotology/idyntree/pull/903).
+- Implement iDynTree base type `type_caster` for pybind11 bindings. In other word, `VectorDynSize`,`VectorFixSize`, `MatrixDynSize` and `MatrixFixSize` are now automatically converted in `NumPy` objects (https://github.com/robotology/idyntree/pull/931).
 
 ### Deprecated
 - The `iDynTree::Visualizer::enviroment()` was deprecated. Please use the `iDynTree::Visualizer::environment()` method instead (https://github.com/robotology/idyntree/pull/903).

bindings/pybind11/CMakeLists.txt

@@ -4,7 +4,8 @@ pybind11_add_module(pybind11_idyntree SYSTEM idyntree.cpp
                                     error_utilities.h error_utilities.cpp
                                     idyntree_model.h idyntree_model.cpp
                                     idyntree_sensors.h idyntree_sensors.cpp
-                                    idyntree_modelio_urdf.h idyntree_modelio_urdf.cpp)
+                                    idyntree_modelio_urdf.h idyntree_modelio_urdf.cpp
+                                    idyntree_type_caster.h)
 
 target_link_libraries(pybind11_idyntree PUBLIC idyntree-core
                                                idyntree-model

bindings/pybind11/idyntree_core.cpp

@@ -1,4 +1,5 @@
 #include "idyntree_core.h"
+#include "idyntree_type_caster.h"
 
 #include <iDynTree/Core/Axis.h>
 #include <iDynTree/Core/Direction.h>
@@ -24,144 +25,14 @@ namespace bindings {
 namespace {
 namespace py = ::pybind11;
 
-void vectorDynSizeClassDefinition(py::class_<VectorDynSize>& vector) {
-  vector.def(py::init())
-      .def(py::init<unsigned>())
-      .def("__getitem__", py::overload_cast<const std::size_t>(
-                              &VectorDynSize::operator(), py::const_))
-      .def("__setitem__",
-           [](VectorDynSize& the_vector, std::size_t index, double new_value) {
-             the_vector(index) = new_value;
-           })
-      .def(
-          "__iter__",
-          [](const VectorDynSize& s) {
-            return py::make_iterator(s.begin(), s.end());
-          },
-          py::keep_alive<
-              0, 1>() /* Essential: keep object alive while iterator exists */)
-      .def("__len__", &VectorDynSize::size)
-      .def("set_zero", &VectorDynSize::zero)
-      .def("resize", &VectorDynSize::resize)
-      .def("__repr__", &VectorDynSize::toString)
-      .def_buffer([](VectorDynSize& v) -> py::buffer_info {
-        return py::buffer_info(
-            v.data(),                                /* Pointer to buffer */
-            sizeof(double),                          /* Size of one scalar */
-            py::format_descriptor<double>::format(), /* Python struct-style
-                                                        format descriptor */
-            1,                                       /* Number of dimensions */
-            {v.size()},                              /* Buffer dimensions */
-            {sizeof(double)} /* Strides (in bytes) for each index */
-        );
-      });
-}
-
-template <unsigned size>
-void createFixSizeVector(pybind11::module& module,
-                         const std::string& class_name) {
-  py::class_<VectorFixSize<size>>(module, class_name.c_str(),
-                                  py::buffer_protocol())
-      .def(py::init())
-      .def("__getitem__", py::overload_cast<const std::size_t>(
-                              &VectorFixSize<size>::operator(), py::const_))
-      .def("__setitem__",
-           [](VectorFixSize<size>& the_vector, std::size_t index,
-              double new_value) { the_vector(index) = new_value; })
-      .def("__len__", &VectorFixSize<size>::size)
-      .def(
-          "__iter__",
-          [](const VectorFixSize<size>& s) {
-            return py::make_iterator(s.begin(), s.end());
-          },
-          py::keep_alive<
-              0, 1>() /* Essential: keep object alive while iterator exists */)
-      .def("set_zero", &VectorFixSize<size>::zero)
-      .def("__repr__", &VectorFixSize<size>::toString)
-      .def_buffer([](VectorFixSize<size>& v) -> py::buffer_info {
-        return py::buffer_info(
-            v.data(),                                /* Pointer to buffer */
-            sizeof(double),                          /* Size of one scalar */
-            py::format_descriptor<double>::format(), /* Python struct-style
-                                                        format descriptor */
-            1,                                       /* Number of dimensions */
-            {v.size()},                              /* Buffer dimensions */
-            {sizeof(double)} /* Strides (in bytes) for each index */
-        );
-      });
-}
-
-void matrixDynSizeClassDefinition(py::class_<MatrixDynSize>& matrix) {
-  matrix.def(py::init())
-      .def(py::init<unsigned, unsigned>())
-      .def("__getitem__",
-           [](MatrixDynSize& matrix,
-              std::pair<std::size_t, std::size_t> indices) {
-             return matrix.getVal(indices.first, indices.second);
-           })
-      .def("__setitem__",
-           [](MatrixDynSize& matrix,
-              std::pair<std::size_t, std::size_t> indices, double item) {
-             return matrix.setVal(indices.first, indices.second, item);
-           })
-      .def("rows", &MatrixDynSize::rows)
-      .def("cols", &MatrixDynSize::cols)
-      .def("set_zero", &MatrixDynSize::zero)
-      .def("resize", &MatrixDynSize::resize)
-      .def("__repr__", &MatrixDynSize::toString)
-      .def_buffer([](MatrixDynSize& m) -> py::buffer_info {
-        return py::buffer_info(
-            m.data(),                                /* Pointer to buffer */
-            sizeof(double),                          /* Size of one scalar */
-            py::format_descriptor<double>::format(), /* Python struct-style
-                                                        format descriptor */
-            2,                                       /* Number of dimensions */
-            {m.rows(), m.cols()},                    /* Buffer dimensions */
-            {sizeof(double) * m.cols(), /* Strides (in bytes) for each index */
-             sizeof(double)});
-      });
-}
-
-template <unsigned rows, unsigned cols>
-void createFixSizeMatrix(pybind11::module& module,
-                         const std::string& class_name) {
-  py::class_<MatrixFixSize<rows, cols>>(module, class_name.c_str(),
-                                        py::buffer_protocol())
-      .def(py::init())
-      .def("__getitem__",
-           [](MatrixFixSize<rows, cols>& matrix,
-              std::pair<std::size_t, std::size_t> indices) {
-             return matrix.getVal(indices.first, indices.second);
-           })
-      .def("__setitem__",
-           [](MatrixFixSize<rows, cols>& matrix,
-              std::pair<std::size_t, std::size_t> indices, double item) {
-             return matrix.setVal(indices.first, indices.second, item);
-           })
-      .def("rows", &MatrixFixSize<rows, cols>::rows)
-      .def("cols", &MatrixFixSize<rows, cols>::cols)
-      .def("set_zero", &MatrixFixSize<rows, cols>::zero)
-      .def("__repr__", &MatrixFixSize<rows, cols>::toString)
-      .def_buffer([](MatrixFixSize<rows, cols>& m) -> py::buffer_info {
-        return py::buffer_info(
-            m.data(),                                /* Pointer to buffer */
-            sizeof(double),                          /* Size of one scalar */
-            py::format_descriptor<double>::format(), /* Python struct-style
-                                                        format descriptor */
-            2,                                       /* Number of dimensions */
-            {m.rows(), m.cols()},                    /* Buffer dimensions */
-            {sizeof(double) * m.cols(), /* Strides (in bytes) for each index */
-             sizeof(double)});
-      });
-}
 
 void transformClassDefinition(py::class_<Transform>& transform) {
   transform.def(py::init())
       .def(py::init<const Rotation&, const Position&>())
       .def(py::init<const MatrixFixSize<4, 4>&>())
       .def_static("Identity", &Transform::Identity)
-      .def_property_readonly("rotation", &Transform::getRotation)
-      .def_property_readonly("position", &Transform::getPosition)
+      .def_property("rotation", &Transform::getRotation, &Transform::setRotation)
+      .def_property("position", &Transform::getPosition,  &Transform::setPosition)
       .def("inverse", &Transform::inverse)
       .def(py::self * py::self)
       .def(
@@ -179,89 +50,64 @@ void transformClassDefinition(py::class_<Transform>& transform) {
 }  // namespace
 
 void iDynTreeCoreBindings(pybind11::module& module) {
-  // Vectors and matrices.
-  py::class_<VectorDynSize> vector_dyn(module, "VectorDynSize",
-                                       py::buffer_protocol());
-  vectorDynSizeClassDefinition(vector_dyn);
-  createFixSizeVector<3>(module, "Vector3");
-  createFixSizeVector<4>(module, "Vector4");
-  createFixSizeVector<6>(module, "Vector6");
-
-  py::class_<MatrixDynSize> matrix_dyn(module, "MatrixDynSize",
-                                       py::buffer_protocol());
-  matrixDynSizeClassDefinition(matrix_dyn);
-  createFixSizeMatrix<3, 3>(module, "Matrix3x3");
-  createFixSizeMatrix<4, 4>(module, "Matrix4x4");
-  createFixSizeMatrix<6, 6>(module, "Matrix6x6");
-
-  // Positions, Rotations and Transforms.
-  py::class_<PositionRaw, VectorFixSize<3>>(module, "_PositionRaw")
-      // Do not expose constructor as we do not want users to use this class.
-      .def("__repr__", &PositionRaw::toString);
-
-  py::class_<Position, PositionRaw>(module, "Position")
-      .def(py::init())
-      .def(py::init<double, double, double>())
-      .def(py::self + py::self)
-      .def(py::self - py::self)
-      .def(-py::self)
-      .def_static("Zero", &Position::Zero);
-
-  py::class_<RotationRaw, MatrixFixSize<3, 3>>(module, "_RotationRaw")
-      // Do not expose constructor as we do not want users to use this class.
-      .def("__repr__", &RotationRaw::toString);
-
-  py::class_<Rotation, RotationRaw>(module, "Rotation")
-      .def(py::init())
-      .def(py::init<double, double, double,  //
-                    double, double, double,  //
-                    double, double, double>())
-      .def("inverse", &Rotation::inverse)
-      .def(py::self * py::self)
-      .def(
-          "__mul__",
-          [](const Rotation& r, const Position& p) -> Position {
-            return r * p;
-          },
-          py::is_operator())
-      .def_static("Identity", &Rotation::Identity);
-
-  py::class_<Transform> transform(module, "Transform");
-  transformClassDefinition(transform);
-
-  // Other classes.
-  py::class_<Direction, VectorFixSize<3>>(module, "Direction")
-      .def(py::init<double, double, double>());
-
-  py::class_<Axis>(module, "Axis")
-      .def(py::init<const Direction&, const Position&>())
-      .def_property("direction", &Axis::getDirection, &Axis::setDirection)
-      .def_property("origin", &Axis::getOrigin, &Axis::setOrigin)
-      .def("__repr__", &Axis::toString);
-
-  py::class_<RotationalInertiaRaw, MatrixFixSize<3, 3>>(module,
-                                                        "RotationalInertia")
-      .def(py::init());
-
-  py::class_<SpatialInertiaRaw>(module, "_SpatialInertiaRaw")
-      .def("from_rotational_inertia_wrt_center_of_mass",
-           &SpatialInertiaRaw::fromRotationalInertiaWrtCenterOfMass)
-      .def("get_mass", &SpatialInertiaRaw::getMass)
-      .def("get_center_of_mass", &SpatialInertiaRaw::getCenterOfMass)
-      .def("get_rotational_inertia_wrt_frame_origin",
-           &SpatialInertiaRaw::getRotationalInertiaWrtFrameOrigin)
-      .def("get_rotational_inertia_wrt_center_of_mass",
-           &SpatialInertiaRaw::getRotationalInertiaWrtCenterOfMass);
 
-  py::class_<SpatialInertia, SpatialInertiaRaw>(module, "SpatialInertia")
-      .def(py::init())
-      .def(py::init<double, const PositionRaw&, const RotationalInertiaRaw&>())
-      .def_static("Zero", &SpatialInertia::Zero)
-      .def("as_matrix", &SpatialInertia::asMatrix)
-      .def(py::self + py::self)
-      .def("__repr__", [](const SpatialInertia& inertia) {
-        return inertia.asMatrix().toString();
-      });
+    py::class_<Rotation>(module, "Rotation")
+        .def(py::init())
+        .def(py::init<double,
+                      double,
+                      double, //
+                      double,
+                      double,
+                      double, //
+                      double,
+                      double,
+                      double>())
+        .def("inverse", &Rotation::inverse)
+        .def(py::self * py::self)
+        .def(
+            "__mul__",
+            [](const Rotation& r, const Position& p) -> Position { return r * p; },
+            py::is_operator())
+        .def_static("Identity", &Rotation::Identity)
+        .def("__repr__", &Rotation::toString)
+        .def("to_numpy",
+             [](const Rotation& impl) {
+                 iDynTree::Matrix3x3 m(impl.data(), 3, 3);
+                 return m;
+             })
+        .def("__getitem__",
+             [](const Rotation& matrix, std::pair<std::size_t, std::size_t> indices) {
+                 return matrix.getVal(indices.first, indices.second);
+             });
+
+    py::class_<Transform> transform(module, "Transform");
+    transformClassDefinition(transform);
+
+    // Other classes.
+    py::class_<Axis>(module, "Axis")
+        .def(py::init<const Direction&, const Position&>())
+        .def_property("direction", &Axis::getDirection, &Axis::setDirection)
+        .def_property("origin", &Axis::getOrigin, &Axis::setOrigin)
+        .def("__repr__", &Axis::toString);
+
+    py::class_<SpatialInertiaRaw>(module, "_SpatialInertiaRaw")
+        .def("from_rotational_inertia_wrt_center_of_mass",
+             &SpatialInertiaRaw::fromRotationalInertiaWrtCenterOfMass)
+        .def("get_mass", &SpatialInertiaRaw::getMass)
+        .def("get_center_of_mass", &SpatialInertiaRaw::getCenterOfMass)
+        .def("get_rotational_inertia_wrt_frame_origin",
+             &SpatialInertiaRaw::getRotationalInertiaWrtFrameOrigin)
+        .def("get_rotational_inertia_wrt_center_of_mass",
+             &SpatialInertiaRaw::getRotationalInertiaWrtCenterOfMass);
+
+    py::class_<SpatialInertia, SpatialInertiaRaw>(module, "SpatialInertia")
+        .def(py::init())
+        .def(py::init<double, const PositionRaw&, const RotationalInertiaRaw&>())
+        .def_static("Zero", &SpatialInertia::Zero)
+        .def("as_matrix", &SpatialInertia::asMatrix)
+        .def(py::self + py::self)
+        .def("__repr__",
+             [](const SpatialInertia& inertia) { return inertia.asMatrix().toString(); });
 }
 }  // namespace bindings
 }  // namespace iDynTree

bindings/pybind11/idyntree_model.cpp

@@ -1,4 +1,5 @@
 #include "idyntree_model.h"
+#include "idyntree_type_caster.h"
 
 #include "error_utilities.h"
 

bindings/pybind11/idyntree_modelio_urdf.cpp

@@ -1,6 +1,6 @@
 #include "idyntree_modelio_urdf.h"
-
 #include "error_utilities.h"
+#include "idyntree_type_caster.h"
 
 #include <string>
 #include <iDynTree/ModelIO/ModelExporter.h>

bindings/pybind11/idyntree_sensors.cpp

@@ -1,5 +1,6 @@
 #include "idyntree_sensors.h"
 #include "error_utilities.h"
+#include "idyntree_type_caster.h"
 
 #include <pybind11/operators.h>
 #include <pybind11/pybind11.h>