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diff --git a/source/blender/functions/FN_attributes_ref.hh b/source/blender/functions/FN_attributes_ref.hh
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+++ b/source/blender/functions/FN_attributes_ref.hh
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+/*
+ * 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.
+ */
+
+#ifndef __FN_ATTRIBUTES_REF_HH__
+#define __FN_ATTRIBUTES_REF_HH__
+
+/** \file
+ * \ingroup fn
+ *
+ * An AttributesRef references multiple arrays of equal length. Each array has a corresponding name
+ * and index.
+ */
+
+#include <optional>
+
+#include "FN_spans.hh"
+
+#include "BLI_linear_allocator.hh"
+#include "BLI_map.hh"
+#include "BLI_utility_mixins.hh"
+#include "BLI_vector_set.hh"
+
+namespace blender::fn {
+
+class AttributesInfo;
+
+class AttributesInfoBuilder : NonCopyable, NonMovable {
+ private:
+  LinearAllocator<> allocator_;
+  VectorSet<std::string> names_;
+  Vector<const CPPType *> types_;
+  Vector<void *> defaults_;
+
+  friend AttributesInfo;
+
+ public:
+  AttributesInfoBuilder() = default;
+  ~AttributesInfoBuilder();
+
+  template<typename T> bool add(StringRef name, const T &default_value)
+  {
+    return this->add(name, CPPType::get<T>(), (const void *)&default_value);
+  }
+
+  bool add(StringRef name, const CPPType &type, const void *default_value = nullptr);
+};
+
+/**
+ * Stores which attributes are in an AttributesRef. Every attribute has a unique index, a unique
+ * name, a type and a default value.
+ */
+class AttributesInfo : NonCopyable, NonMovable {
+ private:
+  LinearAllocator<> allocator_;
+  Map<StringRefNull, int> index_by_name_;
+  Vector<StringRefNull> name_by_index_;
+  Vector<const CPPType *> type_by_index_;
+  Vector<void *> defaults_;
+
+ public:
+  AttributesInfo() = default;
+  AttributesInfo(const AttributesInfoBuilder &builder);
+  ~AttributesInfo();
+
+  int size() const
+  {
+    return name_by_index_.size();
+  }
+
+  IndexRange index_range() const
+  {
+    return name_by_index_.index_range();
+  }
+
+  StringRefNull name_of(int index) const
+  {
+    return name_by_index_[index];
+  }
+
+  int index_of(StringRef name) const
+  {
+    return index_by_name_.lookup_as(name);
+  }
+
+  const void *default_of(int index) const
+  {
+    return defaults_[index];
+  }
+
+  const void *default_of(StringRef name) const
+  {
+    return this->default_of(this->index_of(name));
+  }
+
+  template<typename T> const T &default_of(int index) const
+  {
+    BLI_assert(type_by_index_[index]->is<T>());
+    return *(T *)defaults_[index];
+  }
+
+  template<typename T> const T &default_of(StringRef name) const
+  {
+    return this->default_of<T>(this->index_of(name));
+  }
+
+  const CPPType &type_of(int index) const
+  {
+    return *type_by_index_[index];
+  }
+
+  const CPPType &type_of(StringRef name) const
+  {
+    return this->type_of(this->index_of(name));
+  }
+
+  bool has_attribute(StringRef name, const CPPType &type) const
+  {
+    return this->try_index_of(name, type) >= 0;
+  }
+
+  int try_index_of(StringRef name) const
+  {
+    return index_by_name_.lookup_default_as(name, -1);
+  }
+
+  int try_index_of(StringRef name, const CPPType &type) const
+  {
+    int index = this->try_index_of(name);
+    if (index == -1) {
+      return -1;
+    }
+    else if (this->type_of(index) == type) {
+      return index;
+    }
+    else {
+      return -1;
+    }
+  }
+};
+
+/**
+ * References multiple arrays that match the description of an AttributesInfo instance. This class
+ * is supposed to be relatively cheap to copy. It does not own any of the arrays itself.
+ */
+class MutableAttributesRef {
+ private:
+  const AttributesInfo *info_;
+  Span<void *> buffers_;
+  IndexRange range_;
+
+  friend class AttributesRef;
+
+ public:
+  MutableAttributesRef(const AttributesInfo &info, Span<void *> buffers, int64_t size)
+      : MutableAttributesRef(info, buffers, IndexRange(size))
+  {
+  }
+
+  MutableAttributesRef(const AttributesInfo &info, Span<void *> buffers, IndexRange range)
+      : info_(&info), buffers_(buffers), range_(range)
+  {
+  }
+
+  int64_t size() const
+  {
+    return range_.size();
+  }
+
+  IndexRange index_range() const
+  {
+    return IndexRange(this->size());
+  }
+
+  const AttributesInfo &info() const
+  {
+    return *info_;
+  }
+
+  GMutableSpan get(int index) const
+  {
+    const CPPType &type = info_->type_of(index);
+    void *ptr = POINTER_OFFSET(buffers_[index], type.size() * range_.start());
+    return GMutableSpan(type, ptr, range_.size());
+  }
+
+  GMutableSpan get(StringRef name) const
+  {
+    return this->get(info_->index_of(name));
+  }
+
+  template<typename T> MutableSpan<T> get(int index) const
+  {
+    BLI_assert(info_->type_of(index).is<T>());
+    return MutableSpan<T>((T *)buffers_[index] + range_.start(), range_.size());
+  }
+
+  template<typename T> MutableSpan<T> get(StringRef name) const
+  {
+    return this->get<T>(info_->index_of(name));
+  }
+
+  std::optional<GMutableSpan> try_get(StringRef name, const CPPType &type) const
+  {
+    int index = info_->try_index_of(name, type);
+    if (index == -1) {
+      return {};
+    }
+    else {
+      return this->get(index);
+    }
+  }
+
+  template<typename T> std::optional<MutableSpan<T>> try_get(StringRef name) const
+  {
+    int index = info_->try_index_of(name);
+    if (index == -1) {
+      return {};
+    }
+    else if (info_->type_of(index).is<T>()) {
+      return this->get<T>(index);
+    }
+    else {
+      return {};
+    }
+  }
+
+  MutableAttributesRef slice(IndexRange range) const
+  {
+    return this->slice(range.start(), range.size());
+  }
+
+  MutableAttributesRef slice(int64_t start, int64_t size) const
+  {
+    return MutableAttributesRef(*info_, buffers_, range_.slice(start, size));
+  }
+};
+
+class AttributesRef {
+ private:
+  const AttributesInfo *info_;
+  Span<const void *> buffers_;
+  IndexRange range_;
+
+ public:
+  AttributesRef(const AttributesInfo &info, Span<const void *> buffers, int64_t size)
+      : AttributesRef(info, buffers, IndexRange(size))
+  {
+  }
+
+  AttributesRef(const AttributesInfo &info, Span<const void *> buffers, IndexRange range)
+      : info_(&info), buffers_(buffers), range_(range)
+  {
+  }
+
+  AttributesRef(MutableAttributesRef attributes)
+      : info_(attributes.info_), buffers_(attributes.buffers_), range_(attributes.range_)
+  {
+  }
+
+  int64_t size() const
+  {
+    return range_.size();
+  }
+
+  const AttributesInfo &info() const
+  {
+    return *info_;
+  }
+
+  GSpan get(int index) const
+  {
+    const CPPType &type = info_->type_of(index);
+    const void *ptr = POINTER_OFFSET(buffers_[index], type.size() * range_.start());
+    return GSpan(type, ptr, range_.size());
+  }
+
+  GSpan get(StringRef name) const
+  {
+    return this->get(info_->index_of(name));
+  }
+
+  template<typename T> Span<T> get(int index) const
+  {
+    BLI_assert(info_->type_of(index).is<T>());
+    return Span<T>((T *)buffers_[index] + range_.start(), range_.size());
+  }
+
+  template<typename T> Span<T> get(StringRef name) const
+  {
+    return this->get<T>(info_->index_of(name));
+  }
+
+  std::optional<GSpan> try_get(StringRef name, const CPPType &type) const
+  {
+    int64_t index = info_->try_index_of(name, type);
+    if (index == -1) {
+      return {};
+    }
+    else {
+      return this->get(index);
+    }
+  }
+
+  template<typename T> std::optional<Span<T>> try_get(StringRef name) const
+  {
+    int index = info_->try_index_of(name);
+    if (index == -1) {
+      return {};
+    }
+    else if (info_->type_of(index).is<T>()) {
+      return this->get<T>(index);
+    }
+    else {
+      return {};
+    }
+  }
+
+  AttributesRef slice(IndexRange range) const
+  {
+    return this->slice(range.start(), range.size());
+  }
+
+  AttributesRef slice(int64_t start, int64_t size) const
+  {
+    return AttributesRef(*info_, buffers_, range_.slice(start, size));
+  }
+};
+
+}  // namespace blender::fn
+
+#endif /* __FN_ATTRIBUTES_REF_HH__ */