Cleanup: Move geometry component implementations to separate files

Currently the implementations specific to each geometry type are in
the same file. This makes it difficult to tell which code is generic
for all component types and which is specific to a certain type.
The two files, `attribute_access.cc`, and `geometry_set.cc` are
also getting quite long.

This commit splits up the implementation for every geometry component,
and adds an internal header file for the common parts of the attribute
access code. This was discussed with Jacques Lucke.

1 files changed, 735 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/geometry_component_mesh.cc b/source/blender/blenkernel/intern/geometry_component_mesh.cc
new file mode 100644
index 00000000000..03b938942a7
--- /dev/null
+++ b/source/blender/blenkernel/intern/geometry_component_mesh.cc
@@ -0,0 +1,735 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "BLI_listbase.h"
+#include "BLI_threads.h"
+
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+#include "DNA_object_types.h"
+
+#include "BKE_attribute_access.hh"
+#include "BKE_attribute_math.hh"
+#include "BKE_deform.h"
+#include "BKE_geometry_set.hh"
+#include "BKE_lib_id.h"
+#include "BKE_mesh.h"
+
+#include "attribute_access_intern.hh"
+
+/* Can't include BKE_object_deform.h right now, due to an enum forward declaration.  */
+extern "C" MDeformVert *BKE_object_defgroup_data_create(ID *id);
+
+using blender::bke::ReadAttributePtr;
+
+/* -------------------------------------------------------------------- */
+/** \name Geometry Component Implementation
+ * \{ */
+
+MeshComponent::MeshComponent() : GeometryComponent(GeometryComponentType::Mesh)
+{
+}
+
+MeshComponent::~MeshComponent()
+{
+  this->clear();
+}
+
+GeometryComponent *MeshComponent::copy() const
+{
+  MeshComponent *new_component = new MeshComponent();
+  if (mesh_ != nullptr) {
+    new_component->mesh_ = BKE_mesh_copy_for_eval(mesh_, false);
+    new_component->ownership_ = GeometryOwnershipType::Owned;
+    new_component->vertex_group_names_ = blender::Map(vertex_group_names_);
+  }
+  return new_component;
+}
+
+void MeshComponent::clear()
+{
+  BLI_assert(this->is_mutable());
+  if (mesh_ != nullptr) {
+    if (ownership_ == GeometryOwnershipType::Owned) {
+      BKE_id_free(nullptr, mesh_);
+    }
+    mesh_ = nullptr;
+  }
+  vertex_group_names_.clear();
+}
+
+bool MeshComponent::has_mesh() const
+{
+  return mesh_ != nullptr;
+}
+
+/* Clear the component and replace it with the new mesh. */
+void MeshComponent::replace(Mesh *mesh, GeometryOwnershipType ownership)
+{
+  BLI_assert(this->is_mutable());
+  this->clear();
+  mesh_ = mesh;
+  ownership_ = ownership;
+}
+
+/* This function exists for the same reason as #vertex_group_names_. Non-nodes modifiers need to
+ * be able to replace the mesh data without losing the vertex group names, which may have come
+ * from another object. */
+void MeshComponent::replace_mesh_but_keep_vertex_group_names(Mesh *mesh,
+                                                             GeometryOwnershipType ownership)
+{
+  BLI_assert(this->is_mutable());
+  if (mesh_ != nullptr) {
+    if (ownership_ == GeometryOwnershipType::Owned) {
+      BKE_id_free(nullptr, mesh_);
+    }
+    mesh_ = nullptr;
+  }
+  mesh_ = mesh;
+  ownership_ = ownership;
+}
+
+/* Return the mesh and clear the component. The caller takes over responsibility for freeing the
+ * mesh (if the component was responsible before). */
+Mesh *MeshComponent::release()
+{
+  BLI_assert(this->is_mutable());
+  Mesh *mesh = mesh_;
+  mesh_ = nullptr;
+  return mesh;
+}
+
+void MeshComponent::copy_vertex_group_names_from_object(const Object &object)
+{
+  BLI_assert(this->is_mutable());
+  vertex_group_names_.clear();
+  int index = 0;
+  LISTBASE_FOREACH (const bDeformGroup *, group, &object.defbase) {
+    vertex_group_names_.add(group->name, index);
+    index++;
+  }
+}
+
+const blender::Map<std::string, int> &MeshComponent::vertex_group_names() const
+{
+  return vertex_group_names_;
+}
+
+/* This is only exposed for the internal attribute API. */
+blender::Map<std::string, int> &MeshComponent::vertex_group_names()
+{
+  return vertex_group_names_;
+}
+
+/* Get the mesh from this component. This method can be used by multiple threads at the same
+ * time. Therefore, the returned mesh should not be modified. No ownership is transferred. */
+const Mesh *MeshComponent::get_for_read() const
+{
+  return mesh_;
+}
+
+/* Get the mesh from this component. This method can only be used when the component is mutable,
+ * i.e. it is not shared. The returned mesh can be modified. No ownership is transferred. */
+Mesh *MeshComponent::get_for_write()
+{
+  BLI_assert(this->is_mutable());
+  if (ownership_ == GeometryOwnershipType::ReadOnly) {
+    mesh_ = BKE_mesh_copy_for_eval(mesh_, false);
+    ownership_ = GeometryOwnershipType::Owned;
+  }
+  return mesh_;
+}
+
+bool MeshComponent::is_empty() const
+{
+  return mesh_ == nullptr;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Attribute Access
+ * \{ */
+
+int MeshComponent::attribute_domain_size(const AttributeDomain domain) const
+{
+  BLI_assert(this->attribute_domain_supported(domain));
+  if (mesh_ == nullptr) {
+    return 0;
+  }
+  switch (domain) {
+    case ATTR_DOMAIN_CORNER:
+      return mesh_->totloop;
+    case ATTR_DOMAIN_POINT:
+      return mesh_->totvert;
+    case ATTR_DOMAIN_EDGE:
+      return mesh_->totedge;
+    case ATTR_DOMAIN_POLYGON:
+      return mesh_->totpoly;
+    default:
+      BLI_assert(false);
+      break;
+  }
+  return 0;
+}
+
+namespace blender::bke {
+
+template<typename T>
+static void adapt_mesh_domain_corner_to_point_impl(const Mesh &mesh,
+                                                   const TypedReadAttribute<T> &attribute,
+                                                   MutableSpan<T> r_values)
+{
+  BLI_assert(r_values.size() == mesh.totvert);
+  attribute_math::DefaultMixer<T> mixer(r_values);
+
+  for (const int loop_index : IndexRange(mesh.totloop)) {
+    const T value = attribute[loop_index];
+    const MLoop &loop = mesh.mloop[loop_index];
+    const int point_index = loop.v;
+    mixer.mix_in(point_index, value);
+  }
+  mixer.finalize();
+}
+
+static ReadAttributePtr adapt_mesh_domain_corner_to_point(const Mesh &mesh,
+                                                          ReadAttributePtr attribute)
+{
+  ReadAttributePtr new_attribute;
+  const CustomDataType data_type = attribute->custom_data_type();
+  attribute_math::convert_to_static_type(data_type, [&](auto dummy) {
+    using T = decltype(dummy);
+    if constexpr (!std::is_void_v<attribute_math::DefaultMixer<T>>) {
+      /* We compute all interpolated values at once, because for this interpolation, one has to
+       * iterate over all loops anyway. */
+      Array<T> values(mesh.totvert);
+      adapt_mesh_domain_corner_to_point_impl<T>(mesh, *attribute, values);
+      new_attribute = std::make_unique<OwnedArrayReadAttribute<T>>(ATTR_DOMAIN_POINT,
+                                                                   std::move(values));
+    }
+  });
+  return new_attribute;
+}
+
+template<typename T>
+static void adapt_mesh_domain_point_to_corner_impl(const Mesh &mesh,
+                                                   const TypedReadAttribute<T> &attribute,
+                                                   MutableSpan<T> r_values)
+{
+  BLI_assert(r_values.size() == mesh.totloop);
+
+  for (const int loop_index : IndexRange(mesh.totloop)) {
+    const int vertex_index = mesh.mloop[loop_index].v;
+    r_values[loop_index] = attribute[vertex_index];
+  }
+}
+
+static ReadAttributePtr adapt_mesh_domain_point_to_corner(const Mesh &mesh,
+                                                          ReadAttributePtr attribute)
+{
+  ReadAttributePtr new_attribute;
+  const CustomDataType data_type = attribute->custom_data_type();
+  attribute_math::convert_to_static_type(data_type, [&](auto dummy) {
+    using T = decltype(dummy);
+    /* It is not strictly necessary to compute the value for all corners here. Instead one could
+     * lazily lookup the mesh topology when a specific index accessed. This can be more efficient
+     * when an algorithm only accesses very few of the corner values. However, for the algorithms
+     * we currently have, precomputing the array is fine. Also, it is easier to implement. */
+    Array<T> values(mesh.totloop);
+    adapt_mesh_domain_point_to_corner_impl<T>(mesh, *attribute, values);
+    new_attribute = std::make_unique<OwnedArrayReadAttribute<T>>(ATTR_DOMAIN_CORNER,
+                                                                 std::move(values));
+  });
+  return new_attribute;
+}
+
+}  // namespace blender::bke
+
+ReadAttributePtr MeshComponent::attribute_try_adapt_domain(ReadAttributePtr attribute,
+                                                           const AttributeDomain new_domain) const
+{
+  if (!attribute) {
+    return {};
+  }
+  if (attribute->size() == 0) {
+    return {};
+  }
+  const AttributeDomain old_domain = attribute->domain();
+  if (old_domain == new_domain) {
+    return attribute;
+  }
+
+  switch (old_domain) {
+    case ATTR_DOMAIN_CORNER: {
+      switch (new_domain) {
+        case ATTR_DOMAIN_POINT:
+          return blender::bke::adapt_mesh_domain_corner_to_point(*mesh_, std::move(attribute));
+        default:
+          break;
+      }
+      break;
+    }
+    case ATTR_DOMAIN_POINT: {
+      switch (new_domain) {
+        case ATTR_DOMAIN_CORNER:
+          return blender::bke::adapt_mesh_domain_point_to_corner(*mesh_, std::move(attribute));
+        default:
+          break;
+      }
+    }
+    default:
+      break;
+  }
+
+  return {};
+}
+
+static Mesh *get_mesh_from_component_for_write(GeometryComponent &component)
+{
+  BLI_assert(component.type() == GeometryComponentType::Mesh);
+  MeshComponent &mesh_component = static_cast<MeshComponent &>(component);
+  return mesh_component.get_for_write();
+}
+
+static const Mesh *get_mesh_from_component_for_read(const GeometryComponent &component)
+{
+  BLI_assert(component.type() == GeometryComponentType::Mesh);
+  const MeshComponent &mesh_component = static_cast<const MeshComponent &>(component);
+  return mesh_component.get_for_read();
+}
+
+namespace blender::bke {
+
+static float3 get_vertex_position(const MVert &vert)
+{
+  return float3(vert.co);
+}
+
+static void set_vertex_position(MVert &vert, const float3 &position)
+{
+  copy_v3_v3(vert.co, position);
+}
+
+static ReadAttributePtr make_vertex_position_read_attribute(const void *data,
+                                                            const int domain_size)
+{
+  return std::make_unique<DerivedArrayReadAttribute<MVert, float3, get_vertex_position>>(
+      ATTR_DOMAIN_POINT, Span<MVert>((const MVert *)data, domain_size));
+}
+
+static WriteAttributePtr make_vertex_position_write_attribute(void *data, const int domain_size)
+{
+  return std::make_unique<
+      DerivedArrayWriteAttribute<MVert, float3, get_vertex_position, set_vertex_position>>(
+      ATTR_DOMAIN_POINT, MutableSpan<MVert>((MVert *)data, domain_size));
+}
+
+static void tag_normals_dirty_when_writing_position(GeometryComponent &component)
+{
+  Mesh *mesh = get_mesh_from_component_for_write(component);
+  if (mesh != nullptr) {
+    mesh->runtime.cd_dirty_vert |= CD_MASK_NORMAL;
+  }
+}
+
+static int get_material_index(const MPoly &mpoly)
+{
+  return static_cast<int>(mpoly.mat_nr);
+}
+
+static void set_material_index(MPoly &mpoly, const int &index)
+{
+  mpoly.mat_nr = static_cast<short>(std::clamp(index, 0, SHRT_MAX));
+}
+
+static ReadAttributePtr make_material_index_read_attribute(const void *data, const int domain_size)
+{
+  return std::make_unique<DerivedArrayReadAttribute<MPoly, int, get_material_index>>(
+      ATTR_DOMAIN_POLYGON, Span<MPoly>((const MPoly *)data, domain_size));
+}
+
+static WriteAttributePtr make_material_index_write_attribute(void *data, const int domain_size)
+{
+  return std::make_unique<
+      DerivedArrayWriteAttribute<MPoly, int, get_material_index, set_material_index>>(
+      ATTR_DOMAIN_POLYGON, MutableSpan<MPoly>((MPoly *)data, domain_size));
+}
+
+static float3 get_vertex_normal(const MVert &vert)
+{
+  float3 result;
+  normal_short_to_float_v3(result, vert.no);
+  return result;
+}
+
+static ReadAttributePtr make_vertex_normal_read_attribute(const void *data, const int domain_size)
+{
+  return std::make_unique<DerivedArrayReadAttribute<MVert, float3, get_vertex_normal>>(
+      ATTR_DOMAIN_POINT, Span<MVert>((const MVert *)data, domain_size));
+}
+
+static void update_vertex_normals_when_dirty(const GeometryComponent &component)
+{
+  const Mesh *mesh = get_mesh_from_component_for_read(component);
+  if (mesh == nullptr) {
+    return;
+  }
+
+  /* Since normals are derived data, const write access to them is okay. However, ensure that
+   * two threads don't use write normals to a mesh at the same time. Note that this relies on
+   * the idempotence of the operation; calculating the normals just fills the MVert struct
+   * rather than allocating new memory. */
+  if (mesh->runtime.cd_dirty_vert & CD_MASK_NORMAL) {
+    ThreadMutex *mesh_eval_mutex = (ThreadMutex *)mesh->runtime.eval_mutex;
+    BLI_mutex_lock(mesh_eval_mutex);
+
+    /* Check again to avoid a second thread needlessly recalculating the same normals. */
+    if (mesh->runtime.cd_dirty_vert & CD_MASK_NORMAL) {
+      BKE_mesh_calc_normals(const_cast<Mesh *>(mesh));
+    }
+
+    BLI_mutex_unlock(mesh_eval_mutex);
+  }
+}
+
+static float2 get_loop_uv(const MLoopUV &uv)
+{
+  return float2(uv.uv);
+}
+
+static void set_loop_uv(MLoopUV &uv, const float2 &co)
+{
+  copy_v2_v2(uv.uv, co);
+}
+
+static ReadAttributePtr make_uvs_read_attribute(const void *data, const int domain_size)
+{
+  return std::make_unique<DerivedArrayReadAttribute<MLoopUV, float2, get_loop_uv>>(
+      ATTR_DOMAIN_CORNER, Span((const MLoopUV *)data, domain_size));
+}
+
+static WriteAttributePtr make_uvs_write_attribute(void *data, const int domain_size)
+{
+  return std::make_unique<DerivedArrayWriteAttribute<MLoopUV, float2, get_loop_uv, set_loop_uv>>(
+      ATTR_DOMAIN_CORNER, MutableSpan((MLoopUV *)data, domain_size));
+}
+
+static Color4f get_loop_color(const MLoopCol &col)
+{
+  Color4f value;
+  rgba_uchar_to_float(value, &col.r);
+  return value;
+}
+
+static void set_loop_color(MLoopCol &col, const Color4f &value)
+{
+  rgba_float_to_uchar(&col.r, value);
+}
+
+static ReadAttributePtr make_vertex_color_read_attribute(const void *data, const int domain_size)
+{
+  return std::make_unique<DerivedArrayReadAttribute<MLoopCol, Color4f, get_loop_color>>(
+      ATTR_DOMAIN_CORNER, Span((const MLoopCol *)data, domain_size));
+}
+
+static WriteAttributePtr make_vertex_color_write_attribute(void *data, const int domain_size)
+{
+  return std::make_unique<
+      DerivedArrayWriteAttribute<MLoopCol, Color4f, get_loop_color, set_loop_color>>(
+      ATTR_DOMAIN_CORNER, MutableSpan((MLoopCol *)data, domain_size));
+}
+
+class VertexWeightWriteAttribute final : public WriteAttribute {
+ private:
+  MDeformVert *dverts_;
+  const int dvert_index_;
+
+ public:
+  VertexWeightWriteAttribute(MDeformVert *dverts, const int totvert, const int dvert_index)
+      : WriteAttribute(ATTR_DOMAIN_POINT, CPPType::get<float>(), totvert),
+        dverts_(dverts),
+        dvert_index_(dvert_index)
+  {
+  }
+
+  void get_internal(const int64_t index, void *r_value) const override
+  {
+    get_internal(dverts_, dvert_index_, index, r_value);
+  }
+
+  void set_internal(const int64_t index, const void *value) override
+  {
+    MDeformWeight *weight = BKE_defvert_ensure_index(&dverts_[index], dvert_index_);
+    weight->weight = *reinterpret_cast<const float *>(value);
+  }
+
+  static void get_internal(const MDeformVert *dverts,
+                           const int dvert_index,
+                           const int64_t index,
+                           void *r_value)
+  {
+    if (dverts == nullptr) {
+      *(float *)r_value = 0.0f;
+      return;
+    }
+    const MDeformVert &dvert = dverts[index];
+    for (const MDeformWeight &weight : Span(dvert.dw, dvert.totweight)) {
+      if (weight.def_nr == dvert_index) {
+        *(float *)r_value = weight.weight;
+        return;
+      }
+    }
+    *(float *)r_value = 0.0f;
+  }
+};
+
+class VertexWeightReadAttribute final : public ReadAttribute {
+ private:
+  const MDeformVert *dverts_;
+  const int dvert_index_;
+
+ public:
+  VertexWeightReadAttribute(const MDeformVert *dverts, const int totvert, const int dvert_index)
+      : ReadAttribute(ATTR_DOMAIN_POINT, CPPType::get<float>(), totvert),
+        dverts_(dverts),
+        dvert_index_(dvert_index)
+  {
+  }
+
+  void get_internal(const int64_t index, void *r_value) const override
+  {
+    VertexWeightWriteAttribute::get_internal(dverts_, dvert_index_, index, r_value);
+  }
+};
+
+/**
+ * This provider makes vertex groups available as float attributes.
+ */
+class VertexGroupsAttributeProvider final : public DynamicAttributesProvider {
+ public:
+  ReadAttributePtr try_get_for_read(const GeometryComponent &component,
+                                    const StringRef attribute_name) const final
+  {
+    BLI_assert(component.type() == GeometryComponentType::Mesh);
+    const MeshComponent &mesh_component = static_cast<const MeshComponent &>(component);
+    const Mesh *mesh = mesh_component.get_for_read();
+    const int vertex_group_index = mesh_component.vertex_group_names().lookup_default_as(
+        attribute_name, -1);
+    if (vertex_group_index < 0) {
+      return {};
+    }
+    if (mesh == nullptr || mesh->dvert == nullptr) {
+      static const float default_value = 0.0f;
+      return std::make_unique<ConstantReadAttribute>(
+          ATTR_DOMAIN_POINT, mesh->totvert, CPPType::get<float>(), &default_value);
+    }
+    return std::make_unique<VertexWeightReadAttribute>(
+        mesh->dvert, mesh->totvert, vertex_group_index);
+  }
+
+  WriteAttributePtr try_get_for_write(GeometryComponent &component,
+                                      const StringRef attribute_name) const final
+  {
+    BLI_assert(component.type() == GeometryComponentType::Mesh);
+    MeshComponent &mesh_component = static_cast<MeshComponent &>(component);
+    Mesh *mesh = mesh_component.get_for_write();
+    if (mesh == nullptr) {
+      return {};
+    }
+    const int vertex_group_index = mesh_component.vertex_group_names().lookup_default_as(
+        attribute_name, -1);
+    if (vertex_group_index < 0) {
+      return {};
+    }
+    if (mesh->dvert == nullptr) {
+      BKE_object_defgroup_data_create(&mesh->id);
+    }
+    else {
+      /* Copy the data layer if it is shared with some other mesh. */
+      mesh->dvert = (MDeformVert *)CustomData_duplicate_referenced_layer(
+          &mesh->vdata, CD_MDEFORMVERT, mesh->totvert);
+    }
+    return std::make_unique<blender::bke::VertexWeightWriteAttribute>(
+        mesh->dvert, mesh->totvert, vertex_group_index);
+  }
+
+  bool try_delete(GeometryComponent &component, const StringRef attribute_name) const final
+  {
+    BLI_assert(component.type() == GeometryComponentType::Mesh);
+    MeshComponent &mesh_component = static_cast<MeshComponent &>(component);
+
+    const int vertex_group_index = mesh_component.vertex_group_names().pop_default_as(
+        attribute_name, -1);
+    if (vertex_group_index < 0) {
+      return false;
+    }
+    Mesh *mesh = mesh_component.get_for_write();
+    if (mesh == nullptr) {
+      return true;
+    }
+    if (mesh->dvert == nullptr) {
+      return true;
+    }
+    for (MDeformVert &dvert : MutableSpan(mesh->dvert, mesh->totvert)) {
+      MDeformWeight *weight = BKE_defvert_find_index(&dvert, vertex_group_index);
+      BKE_defvert_remove_group(&dvert, weight);
+    }
+    return true;
+  }
+
+  bool foreach_attribute(const GeometryComponent &component,
+                         const AttributeForeachCallback callback) const final
+  {
+    BLI_assert(component.type() == GeometryComponentType::Mesh);
+    const MeshComponent &mesh_component = static_cast<const MeshComponent &>(component);
+    for (const auto item : mesh_component.vertex_group_names().items()) {
+      const StringRefNull name = item.key;
+      const int vertex_group_index = item.value;
+      if (vertex_group_index >= 0) {
+        AttributeMetaData meta_data{ATTR_DOMAIN_POINT, CD_PROP_FLOAT};
+        if (!callback(name, meta_data)) {
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+
+  void supported_domains(Vector<AttributeDomain> &r_domains) const final
+  {
+    r_domains.append_non_duplicates(ATTR_DOMAIN_POINT);
+  }
+};
+
+/**
+ * In this function all the attribute providers for a mesh component are created. Most data in this
+ * function is statically allocated, because it does not change over time.
+ */
+static ComponentAttributeProviders create_attribute_providers_for_mesh()
+{
+  static auto update_custom_data_pointers = [](GeometryComponent &component) {
+    Mesh *mesh = get_mesh_from_component_for_write(component);
+    if (mesh != nullptr) {
+      BKE_mesh_update_customdata_pointers(mesh, false);
+    }
+  };
+
+#define MAKE_MUTABLE_CUSTOM_DATA_GETTER(NAME) \
+  [](GeometryComponent &component) -> CustomData * { \
+    Mesh *mesh = get_mesh_from_component_for_write(component); \
+    return mesh ? &mesh->NAME : nullptr; \
+  }
+#define MAKE_CONST_CUSTOM_DATA_GETTER(NAME) \
+  [](const GeometryComponent &component) -> const CustomData * { \
+    const Mesh *mesh = get_mesh_from_component_for_read(component); \
+    return mesh ? &mesh->NAME : nullptr; \
+  }
+
+  static CustomDataAccessInfo corner_access = {MAKE_MUTABLE_CUSTOM_DATA_GETTER(ldata),
+                                               MAKE_CONST_CUSTOM_DATA_GETTER(ldata),
+                                               update_custom_data_pointers};
+  static CustomDataAccessInfo point_access = {MAKE_MUTABLE_CUSTOM_DATA_GETTER(vdata),
+                                              MAKE_CONST_CUSTOM_DATA_GETTER(vdata),
+                                              update_custom_data_pointers};
+  static CustomDataAccessInfo edge_access = {MAKE_MUTABLE_CUSTOM_DATA_GETTER(edata),
+                                             MAKE_CONST_CUSTOM_DATA_GETTER(edata),
+                                             update_custom_data_pointers};
+  static CustomDataAccessInfo polygon_access = {MAKE_MUTABLE_CUSTOM_DATA_GETTER(pdata),
+                                                MAKE_CONST_CUSTOM_DATA_GETTER(pdata),
+                                                update_custom_data_pointers};
+
+#undef MAKE_CONST_CUSTOM_DATA_GETTER
+#undef MAKE_MUTABLE_CUSTOM_DATA_GETTER
+
+  static BuiltinCustomDataLayerProvider position("position",
+                                                 ATTR_DOMAIN_POINT,
+                                                 CD_PROP_FLOAT3,
+                                                 CD_MVERT,
+                                                 BuiltinAttributeProvider::NonCreatable,
+                                                 BuiltinAttributeProvider::Writable,
+                                                 BuiltinAttributeProvider::NonDeletable,
+                                                 point_access,
+                                                 make_vertex_position_read_attribute,
+                                                 make_vertex_position_write_attribute,
+                                                 nullptr,
+                                                 tag_normals_dirty_when_writing_position);
+
+  static BuiltinCustomDataLayerProvider material_index("material_index",
+                                                       ATTR_DOMAIN_POLYGON,
+                                                       CD_PROP_INT32,
+                                                       CD_MPOLY,
+                                                       BuiltinAttributeProvider::NonCreatable,
+                                                       BuiltinAttributeProvider::Writable,
+                                                       BuiltinAttributeProvider::NonDeletable,
+                                                       polygon_access,
+                                                       make_material_index_read_attribute,
+                                                       make_material_index_write_attribute,
+                                                       nullptr,
+                                                       nullptr);
+
+  static BuiltinCustomDataLayerProvider vertex_normal("vertex_normal",
+                                                      ATTR_DOMAIN_POINT,
+                                                      CD_PROP_FLOAT3,
+                                                      CD_MVERT,
+                                                      BuiltinAttributeProvider::NonCreatable,
+                                                      BuiltinAttributeProvider::Readonly,
+                                                      BuiltinAttributeProvider::NonDeletable,
+                                                      point_access,
+                                                      make_vertex_normal_read_attribute,
+                                                      nullptr,
+                                                      update_vertex_normals_when_dirty,
+                                                      nullptr);
+
+  static NamedLegacyCustomDataProvider uvs(ATTR_DOMAIN_CORNER,
+                                           CD_PROP_FLOAT2,
+                                           CD_MLOOPUV,
+                                           corner_access,
+                                           make_uvs_read_attribute,
+                                           make_uvs_write_attribute);
+
+  static NamedLegacyCustomDataProvider vertex_colors(ATTR_DOMAIN_CORNER,
+                                                     CD_PROP_COLOR,
+                                                     CD_MLOOPCOL,
+                                                     corner_access,
+                                                     make_vertex_color_read_attribute,
+                                                     make_vertex_color_write_attribute);
+
+  static VertexGroupsAttributeProvider vertex_groups;
+  static CustomDataAttributeProvider corner_custom_data(ATTR_DOMAIN_CORNER, corner_access);
+  static CustomDataAttributeProvider point_custom_data(ATTR_DOMAIN_POINT, point_access);
+  static CustomDataAttributeProvider edge_custom_data(ATTR_DOMAIN_EDGE, edge_access);
+  static CustomDataAttributeProvider polygon_custom_data(ATTR_DOMAIN_POLYGON, polygon_access);
+
+  return ComponentAttributeProviders({&position, &material_index, &vertex_normal},
+                                     {&uvs,
+                                      &vertex_colors,
+                                      &corner_custom_data,
+                                      &vertex_groups,
+                                      &point_custom_data,
+                                      &edge_custom_data,
+                                      &polygon_custom_data});
+}
+
+}  // namespace blender::bke
+
+const blender::bke::ComponentAttributeProviders *MeshComponent::get_attribute_providers() const
+{
+  static blender::bke::ComponentAttributeProviders providers =
+      blender::bke::create_attribute_providers_for_mesh();
+  return &providers;
+}
+
+/** \} */