1 files changed, 68 insertions, 0 deletions
diff --git a/source/blender/io/usd/intern/usd_reader_xform.h b/source/blender/io/usd/intern/usd_reader_xform.h
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+++ b/source/blender/io/usd/intern/usd_reader_xform.h
@@ -0,0 +1,68 @@
+/*
+ * 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 "usd_reader_prim.h"
+
+namespace blender::io::usd {
+
+class USDXformReader : public USDPrimReader {
+ private:
+  bool use_parent_xform_;
+
+  /* Indicates if the created object is the root of a
+   * transform hierarchy. */
+  bool is_root_xform_;
+
+ public:
+  USDXformReader(const pxr::UsdPrim &prim,
+                 const USDImportParams &import_params,
+                 const ImportSettings &settings)
+      : USDPrimReader(prim, import_params, settings),
+        use_parent_xform_(false),
+        is_root_xform_(is_root_xform_prim())
+  {
+  }
+
+  void create_object(Main *bmain, double motionSampleTime) override;
+  void read_object_data(Main *bmain, double motionSampleTime) override;
+
+  void read_matrix(float r_mat[4][4], const float time, const float scale, bool *r_is_constant);
+
+  bool use_parent_xform() const
+  {
+    return use_parent_xform_;
+  }
+  void set_use_parent_xform(bool flag)
+  {
+    use_parent_xform_ = flag;
+    is_root_xform_ = is_root_xform_prim();
+  }
+
+  bool prim_has_xform_ops() const;
+
+ protected:
+  /* Returns true if the contained USD prim is the root of a transform hierarchy. */
+  bool is_root_xform_prim() const;
+};
+
+}  // namespace blender::io::usd