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diff --git a/source/blender/compositor/intern/COM_BufferRange.h b/source/blender/compositor/intern/COM_BufferRange.h
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+++ b/source/blender/compositor/intern/COM_BufferRange.h
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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.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+#pragma once
+
+#include "BLI_assert.h"
+#include "BLI_rect.h"
+
+#include <iterator>
+
+namespace blender::compositor {
+
+/* Forward declarations. */
+template<typename T> class BufferRangeIterator;
+
+/**
+ * A range of buffer elements.
+ */
+template<typename T> class BufferRange {
+ public:
+  using Iterator = BufferRangeIterator<T>;
+  using ConstIterator = BufferRangeIterator<const T>;
+
+ private:
+  T *start_;
+  /* Number of elements in the range. */
+  int64_t size_;
+  /* Buffer element stride. */
+  int elem_stride_;
+
+ public:
+  constexpr BufferRange() = default;
+
+  /**
+   * Create a buffer range of elements from a given element index.
+   */
+  constexpr BufferRange(T *buffer, int64_t start_elem_index, int64_t size, int elem_stride = 1)
+      : start_(buffer + start_elem_index * elem_stride), size_(size), elem_stride_(elem_stride)
+  {
+  }
+
+  constexpr friend bool operator==(const BufferRange &a, const BufferRange &b)
+  {
+    return a.start_ == b.start_ && a.size_ == b.size_ && a.elem_stride_ == b.elem_stride_;
+  }
+
+  /**
+   * Access an element in the range. Index is relative to range start.
+   */
+  constexpr T *operator[](int64_t index) const
+  {
+    BLI_assert(index >= 0);
+    BLI_assert(index < this->size());
+    return start_ + index * elem_stride_;
+  }
+
+  /**
+   * Get the number of elements in the range.
+   */
+  constexpr int64_t size() const
+  {
+    return size_;
+  }
+
+  constexpr Iterator begin()
+  {
+    return begin_iterator<Iterator>();
+  }
+
+  constexpr Iterator end()
+  {
+    return end_iterator<Iterator>();
+  }
+
+  constexpr ConstIterator begin() const
+  {
+    return begin_iterator<ConstIterator>();
+  }
+
+  constexpr ConstIterator end() const
+  {
+    return end_iterator<ConstIterator>();
+  }
+
+ private:
+  template<typename TIterator> constexpr TIterator begin_iterator() const
+  {
+    if (elem_stride_ == 0) {
+      /* Iterate a single element. */
+      return TIterator(start_, 1);
+    }
+
+    return TIterator(start_, elem_stride_);
+  }
+
+  template<typename TIterator> constexpr TIterator end_iterator() const
+  {
+    if (elem_stride_ == 0) {
+      /* Iterate a single element. */
+      return TIterator(start_ + 1, 1);
+    }
+
+    return TIterator(start_ + size_ * elem_stride_, elem_stride_);
+  }
+};
+
+template<typename T> class BufferRangeIterator {
+ public:
+  using iterator_category = std::input_iterator_tag;
+  using value_type = T *;
+  using pointer = T *const *;
+  using reference = T *const &;
+  using difference_type = std::ptrdiff_t;
+
+ private:
+  T *current_;
+  int elem_stride_;
+
+ public:
+  constexpr BufferRangeIterator() = default;
+
+  constexpr BufferRangeIterator(T *current, int elem_stride = 1)
+      : current_(current), elem_stride_(elem_stride)
+  {
+  }
+
+  constexpr BufferRangeIterator &operator++()
+  {
+    current_ += elem_stride_;
+    return *this;
+  }
+
+  constexpr BufferRangeIterator operator++(int) const
+  {
+    BufferRangeIterator copied_iterator = *this;
+    ++copied_iterator;
+    return copied_iterator;
+  }
+
+  constexpr friend bool operator!=(const BufferRangeIterator &a, const BufferRangeIterator &b)
+  {
+    return a.current_ != b.current_;
+  }
+
+  constexpr friend bool operator==(const BufferRangeIterator &a, const BufferRangeIterator &b)
+  {
+    return a.current_ == b.current_;
+  }
+
+  constexpr T *operator*() const
+  {
+    return current_;
+  }
+};
+
+}  // namespace blender::compositor