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diff --git a/extern/draco/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_transform_base.h b/extern/draco/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_transform_base.h
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+++ b/extern/draco/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_transform_base.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_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_TRANSFORM_BASE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_TRANSFORM_BASE_H_
+
+#include <limits>
+#include <vector>
+
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/macros.h"
+
+namespace draco {
+
+// PredictionSchemeWrapTransform uses the min and max bounds of the original
+// data to wrap stored correction values around these bounds centered at 0,
+// i.e., when the range of the original values O is between <MIN, MAX> and
+// N = MAX-MIN, we can then store any correction X = O - P, as:
+//        X + N,   if X < -N / 2
+//        X - N,   if X > N / 2
+//        X        otherwise
+// To unwrap this value, the decoder then simply checks whether the final
+// corrected value F = P + X is out of the bounds of the input values.
+// All out of bounds values are unwrapped using
+//        F + N,   if F < MIN
+//        F - N,   if F > MAX
+// This wrapping can reduce the number of unique values, which translates to a
+// better entropy of the stored values and better compression rates.
+template <typename DataTypeT>
+class PredictionSchemeWrapTransformBase {
+ public:
+  PredictionSchemeWrapTransformBase()
+      : num_components_(0),
+        min_value_(0),
+        max_value_(0),
+        max_dif_(0),
+        max_correction_(0),
+        min_correction_(0) {}
+
+  static constexpr PredictionSchemeTransformType GetType() {
+    return PREDICTION_TRANSFORM_WRAP;
+  }
+
+  void Init(int num_components) {
+    num_components_ = num_components;
+    clamped_value_.resize(num_components);
+  }
+
+  bool AreCorrectionsPositive() const { return false; }
+
+  inline const DataTypeT *ClampPredictedValue(
+      const DataTypeT *predicted_val) const {
+    for (int i = 0; i < this->num_components(); ++i) {
+      if (predicted_val[i] > max_value_) {
+        clamped_value_[i] = max_value_;
+      } else if (predicted_val[i] < min_value_) {
+        clamped_value_[i] = min_value_;
+      } else {
+        clamped_value_[i] = predicted_val[i];
+      }
+    }
+    return &clamped_value_[0];
+  }
+
+  // TODO(hemmer): Consider refactoring to avoid this dummy.
+  int quantization_bits() const {
+    DRACO_DCHECK(false);
+    return -1;
+  }
+
+ protected:
+  bool InitCorrectionBounds() {
+    const int64_t dif =
+        static_cast<int64_t>(max_value_) - static_cast<int64_t>(min_value_);
+    if (dif < 0 || dif >= std::numeric_limits<DataTypeT>::max()) {
+      return false;
+    }
+    max_dif_ = 1 + static_cast<DataTypeT>(dif);
+    max_correction_ = max_dif_ / 2;
+    min_correction_ = -max_correction_;
+    if ((max_dif_ & 1) == 0) {
+      max_correction_ -= 1;
+    }
+    return true;
+  }
+
+  inline int num_components() const { return num_components_; }
+  inline DataTypeT min_value() const { return min_value_; }
+  inline void set_min_value(const DataTypeT &v) { min_value_ = v; }
+  inline DataTypeT max_value() const { return max_value_; }
+  inline void set_max_value(const DataTypeT &v) { max_value_ = v; }
+  inline DataTypeT max_dif() const { return max_dif_; }
+  inline DataTypeT min_correction() const { return min_correction_; }
+  inline DataTypeT max_correction() const { return max_correction_; }
+
+ private:
+  int num_components_;
+  DataTypeT min_value_;
+  DataTypeT max_value_;
+  DataTypeT max_dif_;
+  DataTypeT max_correction_;
+  DataTypeT min_correction_;
+  // This is in fact just a tmp variable to avoid reallocation.
+  mutable std::vector<DataTypeT> clamped_value_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_TRANSFORM_BASE_H_