1 files changed, 131 insertions, 0 deletions
diff --git a/source/blender/io/usd/intern/usd_reader_prim.h b/source/blender/io/usd/intern/usd_reader_prim.h
new file mode 100644
index 00000000000..5aff52f011f
--- /dev/null
+++ b/source/blender/io/usd/intern/usd_reader_prim.h
@@ -0,0 +1,131 @@
+/*
+ * 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.
+ *
+ * Adapted from the Blender Alembic importer implementation.
+ *
+ * Modifications Copyright (C) 2021 Tangent Animation.
+ * All rights reserved.
+ */
+#pragma once
+
+#include "usd.h"
+
+#include <pxr/usd/usd/prim.h>
+
+struct Main;
+struct Object;
+
+namespace blender::io::usd {
+
+struct ImportSettings {
+  bool do_convert_mat;
+  float conversion_mat[4][4];
+
+  int from_up;
+  int from_forward;
+  float scale;
+  bool is_sequence;
+  bool set_frame_range;
+
+  /* Length and frame offset of file sequences. */
+  int sequence_len;
+  int sequence_offset;
+
+  /* From MeshSeqCacheModifierData.read_flag */
+  int read_flag;
+
+  bool validate_meshes;
+
+  CacheFile *cache_file;
+
+  ImportSettings()
+      : do_convert_mat(false),
+        from_up(0),
+        from_forward(0),
+        scale(1.0f),
+        is_sequence(false),
+        set_frame_range(false),
+        sequence_len(1),
+        sequence_offset(0),
+        read_flag(0),
+        validate_meshes(false),
+        cache_file(NULL)
+  {
+  }
+};
+
+/* Most generic USD Reader. */
+
+class USDPrimReader {
+
+ protected:
+  std::string name_;
+  std::string prim_path_;
+  Object *object_;
+  pxr::UsdPrim prim_;
+  const USDImportParams &import_params_;
+  USDPrimReader *parent_reader_;
+  const ImportSettings *settings_;
+  int refcount_;
+
+ public:
+  USDPrimReader(const pxr::UsdPrim &prim,
+                const USDImportParams &import_params,
+                const ImportSettings &settings);
+  virtual ~USDPrimReader();
+
+  const pxr::UsdPrim &prim() const;
+
+  virtual bool valid() const;
+
+  virtual void create_object(Main *bmain, double motionSampleTime) = 0;
+  virtual void read_object_data(Main * /* bmain */, double /* motionSampleTime */){};
+
+  Object *object() const;
+  void object(Object *ob);
+
+  USDPrimReader *parent() const
+  {
+    return parent_reader_;
+  }
+  void parent(USDPrimReader *parent)
+  {
+    parent_reader_ = parent;
+  }
+
+  /* Since readers might be referenced through handles
+   * maintained by modifiers and constraints, we provide
+   * a reference count to facilitate managing the object
+   * lifetime.
+   * TODO(makowalski): investigate transitioning to using
+   * smart pointers for readers, or, alternatively look into
+   * making the lifetime management more robust, e.g., by
+   * making the destructors protected and implementing deletion
+   * in decref(), etc. */
+  int refcount() const;
+  void incref();
+  void decref();
+
+  const std::string &name() const
+  {
+    return name_;
+  }
+  const std::string &prim_path() const
+  {
+    return prim_path_;
+  }
+};
+
+}  // namespace blender::io::usd