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diff --git a/extern/draco/draco/src/draco/compression/mesh/traverser/mesh_attribute_indices_encoding_observer.h b/extern/draco/draco/src/draco/compression/mesh/traverser/mesh_attribute_indices_encoding_observer.h
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+++ b/extern/draco/draco/src/draco/compression/mesh/traverser/mesh_attribute_indices_encoding_observer.h
@@ -0,0 +1,76 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_MESH_TRAVERSER_MESH_ATTRIBUTE_INDICES_ENCODING_OBSERVER_H_
+#define DRACO_COMPRESSION_MESH_TRAVERSER_MESH_ATTRIBUTE_INDICES_ENCODING_OBSERVER_H_
+
+#include "draco/compression/attributes/mesh_attribute_indices_encoding_data.h"
+#include "draco/compression/attributes/points_sequencer.h"
+#include "draco/mesh/mesh.h"
+
+namespace draco {
+
+// Class that can be used to generate encoding (and decoding) order of attribute
+// values based on the traversal of the encoded mesh. The class should be used
+// as the TraversalObserverT member of a Traverser class such as the
+// DepthFirstTraverser (depth_first_traverser.h).
+// TODO(hemmer): rename to AttributeIndicesCodingTraverserObserver
+template <class CornerTableT>
+class MeshAttributeIndicesEncodingObserver {
+ public:
+  MeshAttributeIndicesEncodingObserver()
+      : att_connectivity_(nullptr),
+        encoding_data_(nullptr),
+        mesh_(nullptr),
+        sequencer_(nullptr) {}
+  MeshAttributeIndicesEncodingObserver(
+      const CornerTableT *connectivity, const Mesh *mesh,
+      PointsSequencer *sequencer,
+      MeshAttributeIndicesEncodingData *encoding_data)
+      : att_connectivity_(connectivity),
+        encoding_data_(encoding_data),
+        mesh_(mesh),
+        sequencer_(sequencer) {}
+
+  // Interface for TraversalObserverT
+
+  void OnNewFaceVisited(FaceIndex /* face */) {}
+
+  inline void OnNewVertexVisited(VertexIndex vertex, CornerIndex corner) {
+    const PointIndex point_id =
+        mesh_->face(FaceIndex(corner.value() / 3))[corner.value() % 3];
+    // Append the visited attribute to the encoding order.
+    sequencer_->AddPointId(point_id);
+
+    // Keep track of visited corners.
+    encoding_data_->encoded_attribute_value_index_to_corner_map.push_back(
+        corner);
+
+    encoding_data_
+        ->vertex_to_encoded_attribute_value_index_map[vertex.value()] =
+        encoding_data_->num_values;
+
+    encoding_data_->num_values++;
+  }
+
+ private:
+  const CornerTableT *att_connectivity_;
+  MeshAttributeIndicesEncodingData *encoding_data_;
+  const Mesh *mesh_;
+  PointsSequencer *sequencer_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_MESH_TRAVERSER_MESH_ATTRIBUTE_INDICES_ENCODING_OBSERVER_H_