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diff --git a/extern/draco/draco/src/draco/compression/mesh/traverser/mesh_traversal_sequencer.h b/extern/draco/draco/src/draco/compression/mesh/traverser/mesh_traversal_sequencer.h
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+// 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_TRAVERSAL_SEQUENCER_H_
+#define DRACO_COMPRESSION_MESH_TRAVERSER_MESH_TRAVERSAL_SEQUENCER_H_
+
+#include "draco/attributes/geometry_indices.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 {
+
+// Sequencer that generates point sequence in an order given by a deterministic
+// traversal on the mesh surface. Note that all attributes encoded with this
+// sequence must share the same connectivity.
+// TODO(hemmer): Consider refactoring such that this is an observer.
+template <class TraverserT>
+class MeshTraversalSequencer : public PointsSequencer {
+ public:
+  MeshTraversalSequencer(const Mesh *mesh,
+                         const MeshAttributeIndicesEncodingData *encoding_data)
+      : mesh_(mesh), encoding_data_(encoding_data), corner_order_(nullptr) {}
+  void SetTraverser(const TraverserT &t) { traverser_ = t; }
+
+  // Function that can be used to set an order in which the mesh corners should
+  // be processed. This is an optional flag used usually only by the encoder
+  // to match the same corner order that is going to be used by the decoder.
+  // Note that |corner_order| should contain only one corner per face (it can
+  // have all corners but only the first encountered corner for each face is
+  // going to be used to start a traversal). If the corner order is not set, the
+  // corners are processed sequentially based on their ids.
+  void SetCornerOrder(const std::vector<CornerIndex> &corner_order) {
+    corner_order_ = &corner_order;
+  }
+
+  bool UpdatePointToAttributeIndexMapping(PointAttribute *attribute) override {
+    const auto *corner_table = traverser_.corner_table();
+    attribute->SetExplicitMapping(mesh_->num_points());
+    const size_t num_faces = mesh_->num_faces();
+    const size_t num_points = mesh_->num_points();
+    for (FaceIndex f(0); f < static_cast<uint32_t>(num_faces); ++f) {
+      const auto &face = mesh_->face(f);
+      for (int p = 0; p < 3; ++p) {
+        const PointIndex point_id = face[p];
+        const VertexIndex vert_id =
+            corner_table->Vertex(CornerIndex(3 * f.value() + p));
+        if (vert_id == kInvalidVertexIndex) {
+          return false;
+        }
+        const AttributeValueIndex att_entry_id(
+            encoding_data_
+                ->vertex_to_encoded_attribute_value_index_map[vert_id.value()]);
+        if (point_id >= num_points || att_entry_id.value() >= num_points) {
+          // There cannot be more attribute values than the number of points.
+          return false;
+        }
+        attribute->SetPointMapEntry(point_id, att_entry_id);
+      }
+    }
+    return true;
+  }
+
+ protected:
+  bool GenerateSequenceInternal() override {
+    // Preallocate memory for storing point indices. We expect the number of
+    // points to be the same as the number of corner table vertices.
+    out_point_ids()->reserve(traverser_.corner_table()->num_vertices());
+
+    traverser_.OnTraversalStart();
+    if (corner_order_) {
+      for (uint32_t i = 0; i < corner_order_->size(); ++i) {
+        if (!ProcessCorner(corner_order_->at(i))) {
+          return false;
+        }
+      }
+    } else {
+      const int32_t num_faces = traverser_.corner_table()->num_faces();
+      for (int i = 0; i < num_faces; ++i) {
+        if (!ProcessCorner(CornerIndex(3 * i))) {
+          return false;
+        }
+      }
+    }
+    traverser_.OnTraversalEnd();
+    return true;
+  }
+
+ private:
+  bool ProcessCorner(CornerIndex corner_id) {
+    return traverser_.TraverseFromCorner(corner_id);
+  }
+
+  TraverserT traverser_;
+  const Mesh *mesh_;
+  const MeshAttributeIndicesEncodingData *encoding_data_;
+  const std::vector<CornerIndex> *corner_order_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_MESH_TRAVERSER_MESH_TRAVERSAL_SEQUENCER_H_