python: expose trade.SceneFieldData.

Like with MeshAttributeData, to be eventually used for populating scenes
from scratch.

doc/python/magnum.trade.rst

@@ -702,6 +702,163 @@
         >>> attribute.custom_value
         17
 
+.. py:class:: magnum.trade.SceneFieldData
+
+    Associates a pair of typed data views with a name, type and other scene
+    field properties. The mapping data view is always one-dimensional. The
+    field data view can be either one-dimensional, for example a NumPy array:
+
+    ..
+        Just to verify the snippet below actually works (don't want the arrows
+        shown in the docs, want to have it nicely wrapped)
+    ..
+        >>> mapping_data = array.array('I', [0, 2, 7])
+        >>> field_data = np.array([(-0.5, 0.0), (+0.5, 0.0), ( 0.0, 0.5)], dtype='2f')
+        >>> translations = trade.SceneFieldData(trade.SceneField.TRANSLATION, trade.SceneMappingType.UNSIGNED_INT, mapping_data, trade.SceneFieldType.VECTOR2, field_data)
+
+    .. code:: py
+
+        mapping_data = array.array('I', [0, 2, 7])
+        field_data = np.array([(-0.5, 0.0),
+                               (+0.5, 0.0),
+                               ( 0.0, 0.5)], dtype='2f')
+        translations = trade.SceneFieldData(trade.SceneField.TRANSLATION,
+            trade.SceneMappingType.UNSIGNED_INT, mapping_data,
+            trade.SceneFieldType.VECTOR2, field_data)
+
+    Or it can be two-dimensional, for example by expanding a flat array into a
+    list of two-component vectors:
+
+    ..
+        Again to verify the snippet below actually works
+    ..
+        >>> field_data = array.array('f', [-0.5, 0.0, +0.5, 0.0, 0.0, 0.5])
+        >>> translations = trade.SceneFieldData(trade.SceneField.TRANSLATION, trade.SceneMappingType.UNSIGNED_INT, mapping_data, trade.SceneFieldType.VECTOR2, containers.StridedArrayView1D(field_data).expanded(0, (3, 2)))
+
+    .. code:: py
+
+        field_data = array.array('f', [-0.5, 0.0,
+                                       +0.5, 0.0,
+                                        0.0, 0.5])
+        translations = trade.SceneFieldData(trade.SceneField.TRANSLATION,
+            trade.SceneMappingType.UNSIGNED_INT, mapping_data,
+            trade.SceneFieldType.VECTOR2,
+            containers.StridedArrayView1D(field_data).expanded(0, (3, 2)))
+
+    `Memory ownership and reference counting`_
+    ==========================================
+
+    On initialization, the instance inherits the
+    :ref:`containers.StridedArrayView1D.owner <corrade.containers.StridedArrayView1D.owner>`
+    objects of both views, storing it in the :ref:`mapping_owner` and
+    :ref:`field_owner` fields, meaning that calling :py:`del` on the original
+    data will *not* invalidate the instance.
+
+    `Data access`_
+    ==============
+
+    Similarly to :ref:`SceneData`, the class makes use of Python's dynamic
+    nature and provides direct access to attribute data in their concrete type
+    via :ref:`mapping_data` and :ref:`field_data`. However, the
+    :ref:`SceneFieldData` is considered a low level API and thus a
+    :ref:`containers.StridedArrayView2D <corrade.containers.StridedArrayView2D>`
+    / :ref:`containers.StridedBitArrayView2D <corrade.containers.StridedBitArrayView2D>`
+    is returned always for field data, even for non-array attributes. The
+    returned views inherit the :ref:`mapping_owner` or :ref:`field_owner` and
+    element access coverts to a type corresponding to a particular
+    :ref:`SceneMappingType` or :ref:`SceneFieldType`. For example, extracting
+    the data from the :py:`translations` field created above:
+
+    .. code:: pycon
+
+        >>> mapping = translations.mapping_data
+        >>> field = translations.field_data
+        >>> mapping.owner is mapping_data
+        True
+        >>> field.owner is field_data
+        True
+        >>> mapping[2]
+        7
+        >>> field[2][0]
+        Vector(0, 0.5)
+
+.. py:function:: magnum.trade.SceneFieldData.__init__(self, name: magnum.trade.SceneField, mapping_type: magnum.trade.SceneMappingType, mapping_data: corrade.containers.StridedArrayView1D, field_type: magnum.trade.SceneFieldType, field_data: corrade.containers.StridedArrayView1D, field_array_size: int, flags: magnum.trade.SceneFieldFlags)
+    :raise AssertionError: If :p:`mapping_data` and :p:`field_data` don't have
+        the same size
+    :raise AssertionError: If :p:`field_type` is not valid for :p:`name`
+    :raise AssertionError: If :p:`field_type` is a string type or
+        :ref:`SceneFieldType.BIT`
+    :raise AssertionError: If :p:`mapping_data` stride doesn't fit into 16 bits
+    :raise AssertionError: If :p:`mapping_data` format size is smaller than
+        size of :p:`mapping_type`
+    :raise AssertionError: If :p:`field_data` stride doesn't fit into 16 bits
+    :raise AssertionError: If :p:`field_data` format size is smaller than size
+        of :p:`field_type` at given :p:`field_array_size`
+    :raise AssertionError: If :p:`field_array_size` is non-zero and :p:`name`
+        can't be an array field
+    :raise AssertionError: If :p:`flags` contain
+        :ref:`SceneFieldFlags.OFFSET_ONLY`,
+        :ref:`SceneFieldFlags.NULL_TERMINATED_STRING` or values disallowed for
+        a particular :p:`name`
+.. py:function:: magnum.trade.SceneFieldData.__init__(self, name: magnum.trade.SceneField, mapping_type: magnum.trade.SceneMappingType, mapping_data: corrade.containers.StridedArrayView1D, field_type: magnum.trade.SceneFieldType, field_data: corrade.containers.StridedArrayView2D, field_array_size: int, flags: magnum.trade.SceneFieldFlags)
+    :raise AssertionError: If :p:`mapping_data` and first dimension of
+        :p:`field_data` don't have the same size
+    :raise AssertionError: If :p:`field_type` is not valid for :p:`name`
+    :raise AssertionError: If :p:`field_type` is a string type or
+        :ref:`SceneFieldType.BIT`
+    :raise AssertionError: If :p:`mapping_data` stride doesn't fit into 16 bits
+    :raise AssertionError: If :p:`mapping_data` format size is smaller than
+        size of :p:`mapping_type`
+    :raise AssertionError: If :p:`field_data` first dimension stride doesn't
+        fit into 16 bits
+    :raise AssertionError: If :p:`field_data` second dimension isn't contiguous
+    :raise AssertionError: If :p:`field_data` format size times second
+        dimension size is smaller than size of :p:`field_type` at given :p:`field_array_size`
+    :raise AssertionError: If :p:`field_array_size` is non-zero and :p:`name`
+        can't be an array field
+    :raise AssertionError: If :p:`flags` contain
+        :ref:`SceneFieldFlags.OFFSET_ONLY`,
+        :ref:`SceneFieldFlags.NULL_TERMINATED_STRING` or values disallowed for
+        a particular :p:`name`
+
+.. py:function:: magnum.trade.SceneFieldData.__init__(self, name: magnum.trade.SceneField, mapping_type: magnum.trade.SceneMappingType, mapping_data: corrade.containers.StridedArrayView1D, field_data: corrade.containers.StridedBitArrayView1D, flags: magnum.trade.SceneFieldFlags)
+    :raise AssertionError: If :p:`mapping_data` and :p:`field_data` don't have
+        the same size
+    :raise AssertionError: If :ref:`SceneFieldType.BIT` is not valid for
+        :p:`name`
+    :raise AssertionError: If :p:`mapping_data` stride doesn't fit into 16 bits
+    :raise AssertionError: If :p:`mapping_data` format size is smaller than
+        size of :p:`mapping_type`
+    :raise AssertionError: If :p:`field_data` stride doesn't fit into 16 bits
+    :raise AssertionError: If :p:`flags` contain
+        :ref:`SceneFieldFlags.OFFSET_ONLY`,
+        :ref:`SceneFieldFlags.NULL_TERMINATED_STRING` or values disallowed for
+        a particular :p:`name`
+.. py:function:: magnum.trade.SceneFieldData.__init__(self, name: magnum.trade.SceneField, mapping_type: magnum.trade.SceneMappingType, mapping_data: corrade.containers.StridedArrayView1D, field_data: corrade.containers.StridedBitArrayView2D, flags: magnum.trade.SceneFieldFlags)
+    :raise AssertionError: If :p:`mapping_data` and first dimension of
+        :p:`field_data` don't have the same size
+    :raise AssertionError: If :ref:`SceneFieldType.BIT` is not valid for
+        :p:`name`
+    :raise AssertionError: If :p:`mapping_data` stride doesn't fit into 16 bits
+    :raise AssertionError: If :p:`mapping_data` format size is smaller than
+        size of :p:`mapping_type`
+    :raise AssertionError: If :p:`field_data` first dimension stride doesn't
+        fit into 16 bits
+    :raise AssertionError: If :p:`field_data` second dimension isn't contiguous
+    :raise AssertionError: If :p:`flags` contain
+        :ref:`SceneFieldFlags.OFFSET_ONLY`,
+        :ref:`SceneFieldFlags.NULL_TERMINATED_STRING` or values disallowed for
+        a particular :p:`name`
+
+.. py:property:: magnum.trade.SceneFieldData.field_data
+    :raise NotImplementedError: If :ref:`field_type` is a half-float or string
+        type
+
+    A :ref:`containers.StridedArrayView2D <corrade.containers.StridedArrayView2D>`
+    or :ref:`containers.StridedBitArrayView2D <corrade.containers.StridedBitArrayView2D>`
+    is returned always, non-array attributes have the second dimension size
+    :py:`1`.
+
 .. py:class:: magnum.trade.SceneData
 
     :TODO: remove this line once m.css stops ignoring first caption on a page

doc/python/pages/changelog.rst

@@ -154,9 +154,10 @@ Changelog
 -   Exposed the whole interface of :ref:`trade.MaterialData` including typed
     access to attribute data, together with
     :ref:`trade.AbstractImporter.material()` and related importer APIs
--   Exposed the whole interface of :ref:`trade.SceneData` including typed
+-   Exposed the whole interface of :ref:`trade.SceneData` and
-    access to mapping and field data, together with
+    :ref:`trade.SceneFieldData` including typed access to mapping and field
-    :ref:`trade.AbstractImporter.scene()` and related importer APIs
+    data, together with :ref:`trade.AbstractImporter.scene()` and related
+    importer APIs
 -   Exposed :ref:`Color3.red()` and other convenience constructors (see
     :gh:`mosra/magnum-bindings#12`)
 -   Exposed the :ref:`materialtools`, :ref:`scenetools` and :ref:`text`

src/Magnum/Trade/PythonBindings.h

@@ -31,6 +31,7 @@
 #include "Magnum/Trade/Data.h"
 #include "Magnum/Trade/MaterialData.h" /* :( */
 #include "Magnum/Trade/MeshData.h" /* :( */
+#include "Magnum/Trade/SceneData.h"
 
 namespace Magnum { namespace Trade {
 
@@ -75,8 +76,27 @@ template<class T> PyDataHolder<T> pyDataHolder(T&& data, pybind11::object owner)
     return PyDataHolder<T>{new T{std::move(data)}, std::move(owner)};
 }
 
+/* Compared to PyDataHolder this stores two owner objects. Has to be a template
+   even though it's only ever used for a single type because
+   PYBIND11_DECLARE_HOLDER_TYPE() wants it to be so. */
+template<class T> struct PySceneFieldDataHolder: std::unique_ptr<SceneFieldData> {
+    explicit PySceneFieldDataHolder(SceneFieldData* object): PySceneFieldDataHolder{object, pybind11::none{}, pybind11::none{}} {
+        /* Data without owners can only be empty */
+        CORRADE_INTERNAL_ASSERT(!object->mappingData().data() && !object->fieldData().data());
+    }
+
+    explicit PySceneFieldDataHolder(SceneFieldData* object, pybind11::object mappingOwner, pybind11::object fieldOwner): std::unique_ptr<T>{object}, mappingOwner{std::move(mappingOwner)}, fieldOwner{std::move(fieldOwner)} {}
+
+    pybind11::object mappingOwner, fieldOwner;
+};
+
+inline PySceneFieldDataHolder<SceneFieldData> pySceneFieldDataHolder(SceneFieldData&& data, pybind11::object mappingOwner, pybind11::object fieldOwner) {
+    return PySceneFieldDataHolder<SceneFieldData>{new SceneFieldData{std::move(data)}, std::move(mappingOwner), std::move(fieldOwner)};
+}
+
 }}
 
 PYBIND11_DECLARE_HOLDER_TYPE(T, Magnum::Trade::PyDataHolder<T>)
+PYBIND11_DECLARE_HOLDER_TYPE(T, Magnum::Trade::PySceneFieldDataHolder<T>)
 
 #endif

src/python/magnum/test/test_trade.py

@@ -1277,6 +1277,493 @@ class MeshData(unittest.TestCase):
         with self.assertRaisesRegex(NotImplementedError, "access to VertexFormat.MATRIX2X2 is not implemented yet, sorry"):
             mesh.mutable_attribute(custom_attribute)
 
+class SceneFieldData(unittest.TestCase):
+    def test_init_1d(self):
+        a = array.array('Q', [3, 7, 166, 2872])
+        b = array.array('h', [2, -1, 37, -1])
+        a_refcount = sys.getrefcount(a)
+        b_refcount = sys.getrefcount(b)
+
+        c = trade.SceneFieldData(trade.SceneField.MESH_MATERIAL,
+            trade.SceneMappingType.UNSIGNED_LONG, a,
+            trade.SceneFieldType.SHORT, b,
+            flags=trade.SceneFieldFlags.MULTI_ENTRY|trade.SceneFieldFlags.ORDERED_MAPPING)
+        c_refcount = sys.getrefcount(c)
+        self.assertEqual(c.flags, trade.SceneFieldFlags.MULTI_ENTRY|trade.SceneFieldFlags.ORDERED_MAPPING)
+        self.assertEqual(c.name, trade.SceneField.MESH_MATERIAL)
+        self.assertEqual(c.size, 4)
+        self.assertEqual(c.mapping_type, trade.SceneMappingType.UNSIGNED_LONG)
+        self.assertEqual(c.field_type, trade.SceneFieldType.SHORT)
+        self.assertEqual(c.field_array_size, 0)
+        self.assertIs(c.mapping_owner, a)
+        self.assertIs(c.field_owner, b)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        mapping_data = c.mapping_data
+        self.assertEqual(mapping_data.size, (4,))
+        self.assertEqual(mapping_data.stride, (8,))
+        self.assertEqual(mapping_data.format, 'Q')
+        self.assertIs(mapping_data.owner, a)
+        self.assertEqual(list(mapping_data), [3, 7, 166, 2872])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        field_data = c.field_data
+        self.assertEqual(field_data.size, (4, 1))
+        self.assertEqual(field_data.stride, (2, 2))
+        self.assertEqual(field_data.format, 'h')
+        self.assertIs(field_data.owner, b)
+        # Returns a 2D view always, transpose and take the first element to
+        # "flatten" it.
+        self.assertEqual(list(field_data.transposed(0, 1)[0]), [2, -1, 37, -1])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 2)
+
+        del c
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        del mapping_data
+        del field_data
+        self.assertEqual(sys.getrefcount(a), a_refcount)
+        self.assertEqual(sys.getrefcount(b), b_refcount)
+
+    def test_init_2d(self):
+        a = array.array('I', [0, 1])
+        b = array.array('f', [1.0, 0.0, 0.0,
+                              0.0, -1.0, 0.0])
+        a_refcount = sys.getrefcount(a)
+        b_refcount = sys.getrefcount(b)
+
+        c = trade.SceneFieldData(trade.SceneField.TRANSLATION,
+            trade.SceneMappingType.UNSIGNED_INT, a,
+            trade.SceneFieldType.VECTOR3, containers.StridedArrayView1D(b).expanded(0, (2, 3)),
+            flags=trade.SceneFieldFlags.IMPLICIT_MAPPING)
+        c_refcount = sys.getrefcount(c)
+        self.assertEqual(c.flags, trade.SceneFieldFlags.IMPLICIT_MAPPING)
+        self.assertEqual(c.name, trade.SceneField.TRANSLATION)
+        self.assertEqual(c.size, 2)
+        self.assertEqual(c.mapping_type, trade.SceneMappingType.UNSIGNED_INT)
+        self.assertEqual(c.field_type, trade.SceneFieldType.VECTOR3)
+        self.assertEqual(c.field_array_size, 0)
+        self.assertIs(c.mapping_owner, a)
+        self.assertIs(c.field_owner, b)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        mapping_data = c.mapping_data
+        self.assertEqual(mapping_data.size, (2,))
+        self.assertEqual(mapping_data.stride, (4,))
+        self.assertEqual(mapping_data.format, 'I')
+        self.assertIs(mapping_data.owner, a)
+        self.assertEqual(list(mapping_data), [0, 1])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        field_data = c.field_data
+        self.assertEqual(field_data.size, (2, 1))
+        self.assertEqual(field_data.stride, (12, 12))
+        self.assertEqual(field_data.format, '3f')
+        self.assertIs(field_data.owner, b)
+        # Returns a 2D view always, transpose and take the first element to
+        # "flatten" it.
+        self.assertEqual(list(field_data.transposed(0, 1)[0]), [(1.0, 0.0, 0.0), (0.0, -1.0, 0.0)])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 2)
+
+        del c
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        del mapping_data
+        del field_data
+        self.assertEqual(sys.getrefcount(a), a_refcount)
+        self.assertEqual(sys.getrefcount(b), b_refcount)
+
+    def test_init_1d_array(self):
+        a = array.array('B', [3, 7, 166, 72])
+        b = array.array('Q', [0x0000ffff66663333, 0x00009999aaaacccc, 0x0000bbbb22227777, 0x00001111eeee8888])
+        c = trade.SceneFieldData(trade.SceneField.CUSTOM(666),
+            trade.SceneMappingType.UNSIGNED_BYTE, a,
+            trade.SceneFieldType.UNSIGNED_SHORT, b,
+            field_array_size=3)
+        self.assertEqual(c.flags, trade.SceneFieldFlags.NONE)
+        self.assertEqual(c.name, trade.SceneField.CUSTOM(666))
+        self.assertEqual(c.size, 4)
+        self.assertEqual(c.mapping_type, trade.SceneMappingType.UNSIGNED_BYTE)
+        self.assertEqual(c.field_type, trade.SceneFieldType.UNSIGNED_SHORT)
+        self.assertEqual(c.field_array_size, 3)
+
+        mapping_data = c.mapping_data
+        self.assertEqual(mapping_data.size, (4,))
+        self.assertEqual(mapping_data.stride, (1,))
+        self.assertEqual(mapping_data.format, 'B')
+        self.assertEqual(list(mapping_data), [3, 7, 166, 72])
+
+        field_data = c.field_data
+        self.assertEqual(field_data.size, (4, 3))
+        self.assertEqual(field_data.stride, (8, 2))
+        self.assertEqual(field_data.format, 'H')
+        # Getting all first, second and third array elements. Assumes Little
+        # Endian.
+        self.assertEqual(list(field_data.transposed(0, 1)[0]), [0x3333, 0xcccc, 0x7777, 0x8888])
+        self.assertEqual(list(field_data.transposed(0, 1)[1]), [0x6666, 0xaaaa, 0x2222, 0xeeee])
+        self.assertEqual(list(field_data.transposed(0, 1)[2]), [0xffff, 0x9999, 0xbbbb, 0x1111])
+
+    def test_init_2d_array(self):
+        a = array.array('B', [3, 7, 166, 72])
+        b = array.array('H', [0x3333, 0x6666, 0xffff, 0xcccc, 0xaaaa, 0x9999, 0x7777, 0x2222, 0xbbbb, 0x8888, 0xeeee, 0x1111])
+        c = trade.SceneFieldData(trade.SceneField.CUSTOM(666),
+            trade.SceneMappingType.UNSIGNED_BYTE, a,
+            trade.SceneFieldType.UNSIGNED_SHORT, containers.StridedArrayView1D(b).expanded(0, (4, 3)),
+            field_array_size=3)
+        self.assertEqual(c.flags, trade.SceneFieldFlags.NONE)
+        self.assertEqual(c.name, trade.SceneField.CUSTOM(666))
+        self.assertEqual(c.size, 4)
+        self.assertEqual(c.mapping_type, trade.SceneMappingType.UNSIGNED_BYTE)
+        self.assertEqual(c.field_type, trade.SceneFieldType.UNSIGNED_SHORT)
+        self.assertEqual(c.field_array_size, 3)
+
+        mapping_data = c.mapping_data
+        self.assertEqual(mapping_data.size, (4,))
+        self.assertEqual(mapping_data.stride, (1,))
+        self.assertEqual(mapping_data.format, 'B')
+        self.assertEqual(list(mapping_data), [3, 7, 166, 72])
+
+        field_data = c.field_data
+        self.assertEqual(field_data.size, (4, 3))
+        self.assertEqual(field_data.stride, (6, 2))
+        self.assertEqual(field_data.format, 'H')
+        # Getting all first, second and third array elements. Assumes Little
+        # Endian.
+        self.assertEqual(list(field_data.transposed(0, 1)[0]), [0x3333, 0xcccc, 0x7777, 0x8888])
+        self.assertEqual(list(field_data.transposed(0, 1)[1]), [0x6666, 0xaaaa, 0x2222, 0xeeee])
+        self.assertEqual(list(field_data.transposed(0, 1)[2]), [0xffff, 0x9999, 0xbbbb, 0x1111])
+
+    def test_init_bit_1d(self):
+        a = array.array('H', [3, 7, 166, 2872])
+        b = array.array('b', [1, 0, 1, 0])
+        a_refcount = sys.getrefcount(a)
+        b_refcount = sys.getrefcount(b)
+
+        c = trade.SceneFieldData(trade.SceneField.CUSTOM(1337),
+            trade.SceneMappingType.UNSIGNED_SHORT, a,
+            containers.StridedArrayView1D(b).slice_bit(0),
+            flags=trade.SceneFieldFlags.MULTI_ENTRY|trade.SceneFieldFlags.ORDERED_MAPPING)
+        c_refcount = sys.getrefcount(c)
+        self.assertEqual(c.flags, trade.SceneFieldFlags.MULTI_ENTRY|trade.SceneFieldFlags.ORDERED_MAPPING)
+        self.assertEqual(c.name, trade.SceneField.CUSTOM(1337))
+        self.assertEqual(c.size, 4)
+        self.assertEqual(c.mapping_type, trade.SceneMappingType.UNSIGNED_SHORT)
+        self.assertEqual(c.field_type, trade.SceneFieldType.BIT)
+        self.assertEqual(c.field_array_size, 0)
+        self.assertIs(c.mapping_owner, a)
+        self.assertIs(c.field_owner, b)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        mapping_data = c.mapping_data
+        self.assertEqual(mapping_data.size, (4,))
+        self.assertEqual(mapping_data.stride, (2,))
+        self.assertEqual(mapping_data.format, 'H')
+        self.assertIs(mapping_data.owner, a)
+        self.assertEqual(list(mapping_data), [3, 7, 166, 2872])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        field_data = c.field_data
+        self.assertEqual(field_data.size, (4, 1))
+        self.assertEqual(field_data.offset, 0)
+        self.assertEqual(field_data.stride, (8, 1))
+        self.assertIs(field_data.owner, b)
+        # Returns a 2D view always, transpose and take the first element to
+        # "flatten" it.
+        self.assertEqual(list(field_data.transposed(0, 1)[0]), [True, False, True, False])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 2)
+
+        del c
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        del mapping_data
+        del field_data
+        self.assertEqual(sys.getrefcount(a), a_refcount)
+        self.assertEqual(sys.getrefcount(b), b_refcount)
+
+    def test_init_bit_2d(self):
+        a = array.array('H', [3, 7, 166, 2872])
+        b = containers.BitArray.value_init(4*2)
+        b[0] = True
+        b[1] = True
+        b[4] = True
+        b[7] = True
+        a_refcount = sys.getrefcount(a)
+        b_refcount = sys.getrefcount(b)
+
+        c = trade.SceneFieldData(trade.SceneField.CUSTOM(1337),
+            trade.SceneMappingType.UNSIGNED_SHORT, a,
+            containers.StridedBitArrayView1D(b).expanded(0, (4, 2)),
+            flags=trade.SceneFieldFlags.MULTI_ENTRY|trade.SceneFieldFlags.ORDERED_MAPPING)
+        c_refcount = sys.getrefcount(c)
+        self.assertEqual(c.flags, trade.SceneFieldFlags.MULTI_ENTRY|trade.SceneFieldFlags.ORDERED_MAPPING)
+        self.assertEqual(c.name, trade.SceneField.CUSTOM(1337))
+        self.assertEqual(c.size, 4)
+        self.assertEqual(c.mapping_type, trade.SceneMappingType.UNSIGNED_SHORT)
+        self.assertEqual(c.field_type, trade.SceneFieldType.BIT)
+        self.assertEqual(c.field_array_size, 2)
+        self.assertIs(c.mapping_owner, a)
+        self.assertIs(c.field_owner, b)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        mapping_data = c.mapping_data
+        self.assertEqual(mapping_data.size, (4,))
+        self.assertEqual(mapping_data.stride, (2,))
+        self.assertEqual(mapping_data.format, 'H')
+        self.assertIs(mapping_data.owner, a)
+        self.assertEqual(list(mapping_data), [3, 7, 166, 2872])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        field_data = c.field_data
+        self.assertEqual(field_data.size, (4, 2))
+        self.assertEqual(field_data.offset, 0)
+        self.assertEqual(field_data.stride, (2, 1))
+        self.assertIs(field_data.owner, b)
+        # Getting all first and second array elements
+        self.assertEqual(list(field_data.transposed(0, 1)[0]), [True, False, True, False])
+        self.assertEqual(list(field_data.transposed(0, 1)[1]), [True, False, False, True])
+
+        # The data reference the original array, not the SceneFieldData
+        # instance
+        self.assertEqual(sys.getrefcount(c), c_refcount)
+        self.assertEqual(sys.getrefcount(a), a_refcount + 2)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 2)
+
+        del c
+        self.assertEqual(sys.getrefcount(a), a_refcount + 1)
+        self.assertEqual(sys.getrefcount(b), b_refcount + 1)
+
+        del mapping_data
+        del field_data
+        self.assertEqual(sys.getrefcount(a), a_refcount)
+        self.assertEqual(sys.getrefcount(b), b_refcount)
+
+    def test_init_1d_invalid(self):
+        data = array.array('Q', [0, 0, 0])
+        data_byte = array.array('B', [0, 0, 0])
+        # To check that messages properly handle the case of no format string
+        data_byte_no_format = containers.ArrayView(data_byte)
+        self.assertEqual(containers.StridedArrayView1D(data_byte_no_format).format, None)
+
+        with self.assertRaisesRegex(AssertionError, "expected SceneField.TRANSLATION mapping and field view to have the same size but got 2 and 3"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:2],
+                trade.SceneFieldType.VECTOR2, data)
+        with self.assertRaisesRegex(AssertionError, "SceneFieldType.UNSIGNED_SHORT is not a valid type for SceneField.TRANSLATION"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                trade.SceneFieldType.UNSIGNED_SHORT, data)
+        with self.assertRaisesRegex(AssertionError, "data type B has 1 bytes but SceneMappingType.UNSIGNED_SHORT expects at least 2"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_byte,
+                trade.SceneFieldType.VECTOR2, data)
+        with self.assertRaisesRegex(AssertionError, "data type B has 1 bytes but SceneMappingType.UNSIGNED_SHORT expects at least 2"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_byte_no_format,
+                trade.SceneFieldType.VECTOR2, data)
+        with self.assertRaisesRegex(AssertionError, "data type Q has 8 bytes but SceneFieldType.VECTOR3 expects at least 12"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data,
+                trade.SceneFieldType.VECTOR3, data)
+        with self.assertRaisesRegex(AssertionError, "data type Q has 8 bytes but array of 3 SceneFieldType.FLOAT expects at least 12"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(76),
+                trade.SceneMappingType.UNSIGNED_SHORT, data,
+                trade.SceneFieldType.FLOAT, data, field_array_size=3)
+        with self.assertRaisesRegex(AssertionError, "data type B has 1 bytes but SceneFieldType.SHORT expects at least 2"):
+            trade.SceneFieldData(trade.SceneField.MESH_MATERIAL,
+                trade.SceneMappingType.UNSIGNED_INT, data,
+                trade.SceneFieldType.SHORT, data_byte_no_format)
+        with self.assertRaisesRegex(AssertionError, "expected mapping view stride to fit into 16 bits but got 32768"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, containers.StridedArrayView1D(data)[::4096],
+                trade.SceneFieldType.VECTOR2, data[:1])
+        with self.assertRaisesRegex(AssertionError, "expected mapping view stride to fit into 16 bits but got -32769"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_BYTE, containers.StridedArrayView1D(data_byte)[::32769].flipped(0),
+                trade.SceneFieldType.VECTOR2, data[:1])
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got 32768"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:1],
+                trade.SceneFieldType.VECTOR2, containers.StridedArrayView1D(data)[::4096])
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got -32769"):
+            trade.SceneFieldData(trade.SceneField.CAMERA,
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:1],
+                trade.SceneFieldType.UNSIGNED_BYTE, containers.StridedArrayView1D(data_byte)[::32769].flipped(0))
+        with self.assertRaisesRegex(AssertionError, "SceneField.MESH can't be an array field"):
+            trade.SceneFieldData(trade.SceneField.MESH,
+                trade.SceneMappingType.UNSIGNED_SHORT, data,
+                trade.SceneFieldType.UNSIGNED_SHORT, data, field_array_size=3)
+        with self.assertRaisesRegex(AssertionError, "can't pass SceneFieldFlags.MULTI_ENTRY for a SceneField.TRANSLATION view of SceneFieldType.VECTOR2"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                trade.SceneFieldType.VECTOR2, data, flags=trade.SceneFieldFlags.MULTI_ENTRY)
+        with self.assertRaisesRegex(AssertionError, "use a string constructor for SceneFieldType.STRING_OFFSET16"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(333),
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                trade.SceneFieldType.STRING_OFFSET16, data)
+        with self.assertRaisesRegex(AssertionError, "use a bit constructor for SceneFieldType.BIT"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(333),
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                trade.SceneFieldType.BIT, data)
+
+    def test_init_2d_invalid(self):
+        data_1d = array.array('Q', [0, 0, 0])
+        data = containers.StridedArrayView1D(array.array('I', [0, 0, 0, 0, 0, 0])).expanded(0, (3, 2))
+        data_byte = containers.StridedArrayView1D(array.array('B', [0, 0, 0])).expanded(0, (3, 1))
+        # To check that messages properly handle the case of no format string
+        data_byte_no_format = containers.StridedArrayView1D(containers.ArrayView(array.array('B', [0, 0, 0]))).expanded(0, (3, 1))
+        self.assertEqual(data_byte_no_format.format, None)
+
+        with self.assertRaisesRegex(AssertionError, "expected SceneField.TRANSLATION mapping and field view to have the same size but got 2 and 3"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d[:2],
+                trade.SceneFieldType.VECTOR2, data)
+        with self.assertRaisesRegex(AssertionError, "SceneFieldType.UNSIGNED_SHORT is not a valid type for SceneField.TRANSLATION"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_LONG, data_1d,
+                trade.SceneFieldType.UNSIGNED_SHORT, data)
+        # SceneMappingType size checks are shared with the 1D variant, not
+        # testing here again
+        with self.assertRaisesRegex(AssertionError, "2-item second dimension of data type I has 8 bytes but SceneFieldType.VECTOR3 expects at least 12"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d,
+                trade.SceneFieldType.VECTOR3, data)
+        with self.assertRaisesRegex(AssertionError, "2-item second dimension of data type I has 8 bytes but array of 3 SceneFieldType.FLOAT expects at least 12"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(76),
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d,
+                trade.SceneFieldType.FLOAT, data, field_array_size=3)
+        with self.assertRaisesRegex(AssertionError, "1-item second dimension of data type B has 1 bytes but SceneFieldType.SHORT expects at least 2"):
+            trade.SceneFieldData(trade.SceneField.MESH_MATERIAL,
+                trade.SceneMappingType.UNSIGNED_INT, data_1d,
+                trade.SceneFieldType.SHORT, data_byte_no_format)
+        with self.assertRaisesRegex(AssertionError, "second field view dimension is not contiguous"):
+            trade.SceneFieldData(trade.SceneField.MESH,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d,
+                trade.SceneFieldType.UNSIGNED_SHORT, data[::1,::2])
+        # SceneMappingType stride checks are shared with the 1D variant, not
+        # testing here again
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got 32768"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d[:1],
+                trade.SceneFieldType.VECTOR2, data[::4096])
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got -32769"):
+            trade.SceneFieldData(trade.SceneField.CAMERA,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d[:1],
+                trade.SceneFieldType.UNSIGNED_BYTE, data_byte[::32769].flipped(0))
+        with self.assertRaisesRegex(AssertionError, "SceneField.MESH can't be an array field"):
+            trade.SceneFieldData(trade.SceneField.MESH,
+                trade.SceneMappingType.UNSIGNED_SHORT, data_1d,
+                trade.SceneFieldType.UNSIGNED_SHORT, data, field_array_size=3)
+        with self.assertRaisesRegex(AssertionError, "can't pass SceneFieldFlags.MULTI_ENTRY for a SceneField.TRANSLATION view of SceneFieldType.VECTOR2"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_LONG, data_1d,
+                trade.SceneFieldType.VECTOR2, data, flags=trade.SceneFieldFlags.MULTI_ENTRY)
+        with self.assertRaisesRegex(AssertionError, "use a string constructor for SceneFieldType.STRING_OFFSET16"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(333),
+                trade.SceneMappingType.UNSIGNED_LONG, data_1d,
+                trade.SceneFieldType.STRING_OFFSET16, data)
+        with self.assertRaisesRegex(AssertionError, "use a bit constructor for SceneFieldType.BIT"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(333),
+                trade.SceneMappingType.UNSIGNED_LONG, data_1d,
+                trade.SceneFieldType.BIT, data)
+
+    def test_init_bit_1d_invalid(self):
+        data = array.array('Q', [0, 0, 0])
+        data_bits = containers.BitArray.value_init(3)
+
+        with self.assertRaisesRegex(AssertionError, "expected SceneField.CUSTOM\\(33\\) mapping and field view to have the same size but got 2 and 3"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:2],
+                data_bits)
+        with self.assertRaisesRegex(AssertionError, "SceneFieldType.BIT is not a valid type for SceneField.TRANSLATION"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                data_bits)
+        # SceneMappingType size and stride checks are shared with the non-bit
+        # variant, not testing here again
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got 32768"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:1],
+                containers.StridedBitArrayView1D(data_bits)[::32768])
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got -32769"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:1],
+                containers.StridedBitArrayView1D(data_bits)[::32769].flipped(0))
+        with self.assertRaisesRegex(AssertionError, "can't pass SceneFieldFlags.OFFSET_ONLY for a SceneField.CUSTOM\\(33\\) view of SceneFieldType.BIT"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                data_bits, flags=trade.SceneFieldFlags.OFFSET_ONLY)
+
+    def test_init_bit_2d_invalid(self):
+        data = array.array('Q', [0, 0, 0])
+        data_bits = containers.StridedBitArrayView1D(containers.BitArray.value_init(3*2)).expanded(0, (3, 2))
+        data_bits_one_element = containers.StridedBitArrayView1D(containers.BitArray.value_init(3)).expanded(0, (3, 1))
+
+        with self.assertRaisesRegex(AssertionError, "expected SceneField.CUSTOM\\(33\\) mapping and field view to have the same size but got 2 and 3"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:2],
+                data_bits)
+        with self.assertRaisesRegex(AssertionError, "SceneFieldType.BIT is not a valid type for SceneField.TRANSLATION"):
+            trade.SceneFieldData(trade.SceneField.TRANSLATION,
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                data_bits)
+        # SceneMappingType size and stride checks are shared with the non-bit
+        # variant, not testing here again
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got 32768"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:1],
+                data_bits[::16384])
+        with self.assertRaisesRegex(AssertionError, "expected field view stride to fit into 16 bits but got -32769"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_SHORT, data[:1],
+                data_bits_one_element[::32769].flipped(0))
+        with self.assertRaisesRegex(AssertionError, "can't pass SceneFieldFlags.OFFSET_ONLY for a SceneField.CUSTOM\\(33\\) view of SceneFieldType.BIT"):
+            trade.SceneFieldData(trade.SceneField.CUSTOM(33),
+                trade.SceneMappingType.UNSIGNED_LONG, data,
+                data_bits,
+                flags=trade.SceneFieldFlags.OFFSET_ONLY)
+
 class SceneData(unittest.TestCase):
     def test_custom_field(self):
         # Creating a custom attribute

src/python/magnum/trade.cpp

@@ -739,6 +739,51 @@ template<class T> Containers::PyArrayViewHolder<Containers::PyStridedArrayView<1
     return Containers::pyArrayViewHolder(Containers::PyStridedArrayView<1, T>{data.template transposed<0, 1>()[0], formatStringGetitemSetitem.first(), itemsize, formatStringGetitemSetitem.second(), formatStringGetitemSetitem.third()}, std::move(owner));
 }
 
+void sceneFieldDataConstructorChecks(const Trade::SceneField name, const Trade::SceneMappingType mappingType, const Containers::PyStridedArrayView<1, const char>& mappingData, const Trade::SceneFieldType fieldType, const std::size_t fieldDataSize, const std::ptrdiff_t fieldDataStride, const UnsignedShort fieldArraySize, const Trade::SceneFieldFlag flags) {
+    if(mappingData.size() != fieldDataSize) {
+        PyErr_Format(PyExc_AssertionError, "expected %S mapping and field view to have the same size but got %zu and %zu", py::cast(name).ptr(), mappingData.size(), fieldDataSize);
+        throw py::error_already_set{};
+    }
+    const UnsignedInt mappingTypeSize = Trade::sceneMappingTypeSize(mappingType);
+    if(mappingData.itemsize < mappingTypeSize) {
+        const char* const dataFormat = mappingData.format ? mappingData.format.data() : "B";
+        PyErr_Format(PyExc_AssertionError, "data type %s has %zu bytes but %S expects at least %u", dataFormat, mappingData.itemsize, py::cast(mappingType).ptr(), mappingTypeSize);
+        throw py::error_already_set{};
+    }
+    if(!Trade::Implementation::isSceneFieldTypeCompatibleWithField(name, fieldType)) {
+        PyErr_Format(PyExc_AssertionError, "%S is not a valid type for %S", py::cast(fieldType).ptr(), py::cast(name).ptr());
+        throw py::error_already_set{};
+    }
+    if(mappingData.stride() < -32768 || mappingData.stride() > 32767) {
+        PyErr_Format(PyExc_AssertionError, "expected mapping view stride to fit into 16 bits but got %zi", mappingData.stride());
+        throw py::error_already_set{};
+    }
+    if(fieldDataStride < -32768 || fieldDataStride > 32767) {
+        PyErr_Format(PyExc_AssertionError, "expected field view stride to fit into 16 bits but got %zi", fieldDataStride);
+        throw py::error_already_set{};
+    }
+    if(fieldArraySize && !Trade::Implementation::isSceneFieldArrayAllowed(name)) {
+        PyErr_Format(PyExc_AssertionError, "%S can't be an array field", py::cast(name).ptr());
+        throw py::error_already_set{};
+    }
+    if(const Trade::SceneFieldFlags disallowedFlags = flags & (Trade::SceneFieldFlag::OffsetOnly|Trade::SceneFieldFlag::NullTerminatedString|Trade::Implementation::disallowedSceneFieldFlagsFor(name))) {
+        PyErr_Format(PyExc_AssertionError, "can't pass %S for a %S view of %S", py::cast(Trade::SceneFieldFlag(Containers::enumCastUnderlyingType(disallowedFlags))).ptr(), py::cast(name).ptr(), py::cast(fieldType).ptr());
+        throw py::error_already_set{};
+    }
+}
+
+void sceneFieldDataConstructorChecks(const Trade::SceneField name, const Trade::SceneMappingType mappingType, const Containers::PyStridedArrayView<1, const char>& mappingData, const Trade::SceneFieldType fieldType, const Containers::StridedArrayView1D<const void>& fieldData, const UnsignedShort fieldArraySize, const Trade::SceneFieldFlag flags) {
+    sceneFieldDataConstructorChecks(name, mappingType, mappingData, fieldType, fieldData.size(), fieldData.stride(), fieldArraySize, flags);
+    if(Trade::Implementation::isSceneFieldTypeString(fieldType)) {
+        PyErr_Format(PyExc_AssertionError, "use a string constructor for %S", py::cast(fieldType).ptr());
+        throw py::error_already_set{};
+    }
+    if(fieldType == Trade::SceneFieldType::Bit) {
+        PyErr_Format(PyExc_AssertionError, "use a bit constructor for %S", py::cast(fieldType).ptr());
+        throw py::error_already_set{};
+    }
+}
+
 Containers::Triple<const char*, py::object(*)(const char*), void(*)(char*, py::handle)> accessorsForSceneMappingType(const Trade::SceneMappingType type) {
     switch(type) {
         #define _c(type)                                                    \
@@ -2538,6 +2583,106 @@ void trade(py::module_& m) {
         .value("NONE", Trade::SceneFieldFlag{});
     corrade::enumOperators(sceneFieldFlag);
 
+    py::class_<Trade::SceneFieldData, Trade::PySceneFieldDataHolder<Trade::SceneFieldData>>{m, "SceneFieldData", "Scene field data"}
+        .def(py::init([](Trade::SceneField name, Trade::SceneMappingType mappingType, const Containers::PyStridedArrayView<1, const char>& mappingData, Trade::SceneFieldType fieldType, const Containers::PyStridedArrayView<1, const char>& fieldData, UnsignedShort fieldArraySize, Trade::SceneFieldFlag flags) {
+            sceneFieldDataConstructorChecks(name, mappingType, mappingData, fieldType, fieldData, fieldArraySize, flags);
+            const UnsignedInt fieldTypeSize = Trade::sceneFieldTypeSize(fieldType)*(fieldArraySize ? fieldArraySize : 1);
+            if(fieldData.itemsize < fieldTypeSize) {
+                const char* const dataFormat = fieldData.format ? fieldData.format.data() : "B";
+                if(fieldArraySize)
+                    PyErr_Format(PyExc_AssertionError, "data type %s has %zu bytes but array of %u %S expects at least %u", dataFormat, fieldData.itemsize, UnsignedInt(fieldArraySize), py::cast(fieldType).ptr(), fieldTypeSize);
+                else
+                    PyErr_Format(PyExc_AssertionError, "data type %s has %zu bytes but %S expects at least %u", dataFormat, fieldData.itemsize, py::cast(fieldType).ptr(), fieldTypeSize);
+                throw py::error_already_set{};
+            }
+            return Trade::pySceneFieldDataHolder(Trade::SceneFieldData{name, mappingType, Containers::StridedArrayView1D<const void>{mappingData}, fieldType, Containers::StridedArrayView1D<const void>{fieldData}, fieldArraySize, flags}, pyObjectHolderFor<Containers::PyArrayViewHolder>(mappingData).owner, pyObjectHolderFor<Containers::PyArrayViewHolder>(fieldData).owner);
+        }), "Construct from a 1D field view", py::arg("name"), py::arg("mapping_type"), py::arg("mapping_data"), py::arg("field_type"), py::arg("field_data"),
+            #if PYBIND11_VERSION_MAJOR*100 + PYBIND11_VERSION_MINOR >= 206
+            py::kw_only{}, /* new in pybind11 2.6 */
+            #endif
+            py::arg("field_array_size") = 0, py::arg("flags") = Trade::SceneFieldFlag{})
+        .def(py::init([](Trade::SceneField name, Trade::SceneMappingType mappingType, const Containers::PyStridedArrayView<1, const char>& mappingData, Trade::SceneFieldType fieldType, const Containers::PyStridedArrayView<2, const char>& fieldData, UnsignedShort fieldArraySize, Trade::SceneFieldFlag flags) {
+            if(fieldData.itemsize != std::size_t(fieldData.stride()[1])) {
+                PyErr_SetString(PyExc_AssertionError, "second field view dimension is not contiguous");
+                throw py::error_already_set{};
+            }
+            const Containers::StridedArrayView1D<const void> fieldData1D = fieldData.transposed<0, 1>()[0];
+            sceneFieldDataConstructorChecks(name, mappingType, mappingData, fieldType, fieldData1D, fieldArraySize, flags);
+            const std::size_t secondDimensionSize = fieldData.itemsize*fieldData.size()[1];
+            const UnsignedInt fieldTypeSize = Trade::sceneFieldTypeSize(fieldType)*(fieldArraySize ? fieldArraySize : 1);
+            if(secondDimensionSize < fieldTypeSize) {
+                const char* const dataFormat = fieldData.format ? fieldData.format.data() : "B";
+                if(fieldArraySize)
+                    PyErr_Format(PyExc_AssertionError, "%zu-item second dimension of data type %s has %zu bytes but array of %u %S expects at least %u", fieldData.size()[1], dataFormat, secondDimensionSize, UnsignedInt(fieldArraySize), py::cast(fieldType).ptr(), fieldTypeSize);
+                else
+                    PyErr_Format(PyExc_AssertionError, "%zu-item second dimension of data type %s has %zu bytes but %S expects at least %u", fieldData.size()[1], dataFormat, secondDimensionSize, py::cast(fieldType).ptr(), fieldTypeSize);
+                throw py::error_already_set{};
+            }
+            return Trade::pySceneFieldDataHolder(Trade::SceneFieldData{name, mappingType, Containers::StridedArrayView1D<const void>{mappingData}, fieldType, fieldData1D, fieldArraySize, flags}, pyObjectHolderFor<Containers::PyArrayViewHolder>(mappingData).owner, pyObjectHolderFor<Containers::PyArrayViewHolder>(fieldData).owner);
+        }), "Construct from a 2D field view", py::arg("name"), py::arg("mapping_type"), py::arg("mapping_data"), py::arg("field_type"), py::arg("field_data"),
+            #if PYBIND11_VERSION_MAJOR*100 + PYBIND11_VERSION_MINOR >= 206
+            py::kw_only{}, /* new in pybind11 2.6 */
+            #endif
+            py::arg("field_array_size") = 0, py::arg("flags") = Trade::SceneFieldFlag{})
+        .def(py::init([](Trade::SceneField name, Trade::SceneMappingType mappingType, const Containers::PyStridedArrayView<1, const char>& mappingData, const Containers::StridedBitArrayView1D& fieldData, Trade::SceneFieldFlag flags) {
+            sceneFieldDataConstructorChecks(name, mappingType, mappingData, Trade::SceneFieldType::Bit, fieldData.size(), fieldData.stride(), 0, flags);
+            return Trade::pySceneFieldDataHolder(Trade::SceneFieldData{name, mappingType, Containers::StridedArrayView1D<const void>{mappingData}, fieldData, flags}, pyObjectHolderFor<Containers::PyArrayViewHolder>(mappingData).owner, pyObjectHolderFor<Containers::PyArrayViewHolder>(fieldData).owner);
+        }), "Construct a bit field", py::arg("name"), py::arg("mapping_type"), py::arg("mapping_data"), py::arg("field_data"),
+            #if PYBIND11_VERSION_MAJOR*100 + PYBIND11_VERSION_MINOR >= 206
+            py::kw_only{}, /* new in pybind11 2.6 */
+            #endif
+            py::arg("flags") = Trade::SceneFieldFlag{})
+        .def(py::init([](Trade::SceneField name, Trade::SceneMappingType mappingType, const Containers::PyStridedArrayView<1, const char>& mappingData, const Containers::StridedBitArrayView2D& fieldData, Trade::SceneFieldFlag flags) {
+            if(fieldData.stride()[1] != 1) {
+                PyErr_SetString(PyExc_AssertionError, "second field view dimension is not contiguous");
+                throw py::error_already_set{};
+            }
+            sceneFieldDataConstructorChecks(name, mappingType, mappingData, Trade::SceneFieldType::Bit, fieldData.size()[0], fieldData.stride()[0], fieldData.size()[1], flags);
+            return Trade::pySceneFieldDataHolder(Trade::SceneFieldData{name, mappingType, Containers::StridedArrayView1D<const void>{mappingData}, fieldData, flags}, pyObjectHolderFor<Containers::PyArrayViewHolder>(mappingData).owner, pyObjectHolderFor<Containers::PyArrayViewHolder>(fieldData).owner);
+        }), "Construct an array bit field", py::arg("name"), py::arg("mapping_type"), py::arg("mapping_data"), py::arg("field_data"),
+            #if PYBIND11_VERSION_MAJOR*100 + PYBIND11_VERSION_MINOR >= 206
+            py::kw_only{}, /* new in pybind11 2.6 */
+            #endif
+            py::arg("flags") = Trade::SceneFieldFlag{})
+        .def_property_readonly("flags", [](const Trade::SceneFieldData& self) {
+            return Trade::SceneFieldFlag(Containers::enumCastUnderlyingType(self.flags()));
+        }, "Field flags")
+        .def_property_readonly("name", &Trade::SceneFieldData::name, "Field name")
+        .def_property_readonly("size", &Trade::SceneFieldData::size, "Number of entries")
+        .def_property_readonly("mapping_type", &Trade::SceneFieldData::mappingType, "Object mapping type")
+        .def_property_readonly("mapping_data", [](const Trade::SceneFieldData& self) {
+            return sceneMappingView(self.mappingType(),
+                /* The sceneMappingView() helper needs a 2D array with the
+                   second dimension being element bytes, but information about
+                   the type and its size is subsequently discarded so we don't
+                   need any extra logic here. */
+                Containers::arrayCast<2, const char>(self.mappingData(), 1),
+                pyObjectHolderFor<Trade::PySceneFieldDataHolder>(self).mappingOwner);
+        }, "Object mapping data")
+        .def_property_readonly("field_type", &Trade::SceneFieldData::fieldType, "Field type")
+        .def_property_readonly("field_array_size", &Trade::SceneFieldData::fieldArraySize, "Field array size")
+        .def_property_readonly("field_data", [](const Trade::SceneFieldData& self) {
+            /** @todo annotate the return type properly in the docs */
+            if(self.fieldType() == Trade::SceneFieldType::Bit)
+                return pyCastButNotShitty(Containers::pyArrayViewHolder(self.fieldBitData(), pyObjectHolderFor<Trade::PySceneFieldDataHolder>(self).fieldOwner));
+            /** @todo handle strings, so far they can't even be constructed so
+                this isn't needed */
+
+            const Containers::Triple<const char*, py::object(*)(const char*), void(*)(char*, py::handle)> formatStringGetitemSetitem = accessorsForSceneFieldType(self.fieldType());
+            if(!formatStringGetitemSetitem.first()) {
+                PyErr_Format(PyExc_NotImplementedError, "access to %S is not implemented yet, sorry", py::cast(self.fieldType()).ptr());
+                throw py::error_already_set{};
+            }
+            const std::size_t fieldTypeSize = Trade::sceneFieldTypeSize(self.fieldType());
+            return pyCastButNotShitty(Containers::pyArrayViewHolder(Containers::PyStridedArrayView<2, const char>{Containers::arrayCast<2, const char>(self.fieldData(), fieldTypeSize*(self.fieldArraySize() ? self.fieldArraySize() : 1)).every({1, fieldTypeSize}), formatStringGetitemSetitem.first(), fieldTypeSize, formatStringGetitemSetitem.second(), formatStringGetitemSetitem.third()}, pyObjectHolderFor<Trade::PySceneFieldDataHolder>(self).fieldOwner));
+        }, "Field data")
+        .def_property_readonly("mapping_owner", [](const Trade::SceneFieldData& self) {
+            return pyObjectHolderFor<Trade::PySceneFieldDataHolder>(self).mappingOwner;
+        }, "Mapping memory owner")
+        .def_property_readonly("field_owner", [](const Trade::SceneFieldData& self) {
+            return pyObjectHolderFor<Trade::PySceneFieldDataHolder>(self).fieldOwner;
+        }, "Field memory owner");
+
     py::class_<Trade::SceneData, Trade::PyDataHolder<Trade::SceneData>>{m, "SceneData", "Scene data"}
         .def_property_readonly("data_flags", [](const Trade::SceneData& self) {
             return Trade::DataFlag(Containers::enumCastUnderlyingType(self.dataFlags()));