text: //
  // Copyright 2018 Pixar
  //
  // Licensed under the Apache License, Version 2.0 (the "Apache License")
  // with the following modification; you may not use this file except in
  // compliance with the Apache License and the following modification to it:
  // Section 6. Trademarks. is deleted and replaced with:
  //
  // 6. Trademarks. This License does not grant permission to use the trade
  //    names, trademarks, service marks, or product names of the Licensor
  //    and its affiliates, except as required to comply with Section 4(c) of
  //    the License and to reproduce the content of the NOTICE file.
  //
  // You may obtain a copy of the Apache License at
  //
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the Apache License with the above modification is
  // distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  // KIND, either express or implied. See the Apache License for the specific
  // language governing permissions and limitations under the Apache License.
  //
  #ifndef PXR_USD_PLUGIN_USD_MTLX_READER_H
  #define PXR_USD_PLUGIN_USD_MTLX_READER_H
   
  #include "pxr/pxr.h"
  #include "pxr/usd/plugin/usdMtlx/api.h"
  #include "pxr/usd/sdf/path.h"
  #include "pxr/base/tf/declarePtrs.h"
  #include <MaterialXCore/Document.h>
  
  PXR_NAMESPACE_OPEN_SCOPE
  
  TF_DECLARE_WEAK_PTRS(UsdStage);
  
  /// Translate the MaterialX document in \p mtlx into the stage \p stage.
  /// \p internalPath is a namespace path where converted MaterialX objects
  /// will live. \p externalPath is a namespace path of a prim that will
  /// have all of the look variants.  It will have references into
  /// \p internalPath.  Clients are expected to reference the prim at
  /// \p externalPath to apply looks.
  ///
  /// Note that this method will traverse the materialx network following material
  /// nodes, and does an early exit if no looks are defined in the mtlx document.
  USDMTLX_LOCAL
  void UsdMtlxRead(const MaterialX::ConstDocumentPtr& mtlx,
                   const UsdStagePtr& stage,
                   const SdfPath& internalPath = SdfPath("/MaterialX"),
                   const SdfPath& externalPath = SdfPath("/ModelRoot"));
  
  /// Translate node graphs in the MaterialX document in \p mtlx into the
  /// stage \p stage.  \p internalPath is a namespace path where converted
  /// MaterialX objects will live.
  ///
  /// Note that this method will traverse all the nodegraphs in the mtlx document.
  USDMTLX_LOCAL
  void UsdMtlxReadNodeGraphs(const MaterialX::ConstDocumentPtr& mtlx,
                             const UsdStagePtr& stage,
                             const SdfPath& internalPath = SdfPath("/MaterialX"));
  
  PXR_NAMESPACE_CLOSE_SCOPE
  
  #endif // PXR_USD_PLUGIN_USD_MTLX_READER_H
  