1 files changed, 36 insertions, 0 deletions
diff --git a/source/blender/io/usd/intern/usd_writer_volume.h b/source/blender/io/usd/intern/usd_writer_volume.h
new file mode 100644
index 00000000000..8c1e36b7e53
--- /dev/null
+++ b/source/blender/io/usd/intern/usd_writer_volume.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#pragma once
+
+#include <optional>
+
+#include "BLI_math_vec_types.hh"
+#include "usd_writer_abstract.h"
+
+struct Volume;
+
+namespace blender::io::usd {
+
+/* Writer for writing OpenVDB assets to UsdVolVolume. Volume data is stored in separate .vdb files
+ * which are referenced in USD file. */
+class USDVolumeWriter : public USDAbstractWriter {
+ public:
+  USDVolumeWriter(const USDExporterContext &ctx);
+
+ protected:
+  virtual bool check_is_animated(const HierarchyContext &context) const override;
+  virtual void do_write(HierarchyContext &context) override;
+
+ private:
+  /* Try to ensure that external .vdb file is available for USD to be referenced. Blender can
+   * either reference external OpenVDB data or generate such data internally. Latter option will
+   * mean that `resolve_vdb_file` method will try to export volume data to a new .vdb file. If
+   * successful, this method returns absolute file path to the resolved .vdb file, if not, returns
+   * `std::nullopt`. */
+  std::optional<std::string> resolve_vdb_file(const Volume *volume) const;
+
+  std::optional<std::string> construct_vdb_file_path(const Volume *volume) const;
+  std::optional<std::string> construct_vdb_relative_file_path(
+      const std::string &vdb_file_path) const;
+};
+
+}  // namespace blender::io::usd