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diff --git a/extern/draco/draco/src/draco/compression/bit_coders/direct_bit_decoder.h b/extern/draco/draco/src/draco/compression/bit_coders/direct_bit_decoder.h
new file mode 100644
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+++ b/extern/draco/draco/src/draco/compression/bit_coders/direct_bit_decoder.h
@@ -0,0 +1,90 @@
+// 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.
+//
+// File provides direct encoding of bits with arithmetic encoder interface.
+#ifndef DRACO_COMPRESSION_BIT_CODERS_DIRECT_BIT_DECODER_H_
+#define DRACO_COMPRESSION_BIT_CODERS_DIRECT_BIT_DECODER_H_
+
+#include <vector>
+
+#include "draco/core/decoder_buffer.h"
+
+namespace draco {
+
+class DirectBitDecoder {
+ public:
+  DirectBitDecoder();
+  ~DirectBitDecoder();
+
+  // Sets |source_buffer| as the buffer to decode bits from.
+  bool StartDecoding(DecoderBuffer *source_buffer);
+
+  // Decode one bit. Returns true if the bit is a 1, otherwise false.
+  bool DecodeNextBit() {
+    const uint32_t selector = 1 << (31 - num_used_bits_);
+    if (pos_ == bits_.end()) {
+      return false;
+    }
+    const bool bit = *pos_ & selector;
+    ++num_used_bits_;
+    if (num_used_bits_ == 32) {
+      ++pos_;
+      num_used_bits_ = 0;
+    }
+    return bit;
+  }
+
+  // Decode the next |nbits| and return the sequence in |value|. |nbits| must be
+  // > 0 and <= 32.
+  void DecodeLeastSignificantBits32(int nbits, uint32_t *value) {
+    DRACO_DCHECK_EQ(true, nbits <= 32);
+    DRACO_DCHECK_EQ(true, nbits > 0);
+    const int remaining = 32 - num_used_bits_;
+    if (nbits <= remaining) {
+      if (pos_ == bits_.end()) {
+        *value = 0;
+        return;
+      }
+      *value = (*pos_ << num_used_bits_) >> (32 - nbits);
+      num_used_bits_ += nbits;
+      if (num_used_bits_ == 32) {
+        ++pos_;
+        num_used_bits_ = 0;
+      }
+    } else {
+      if (pos_ + 1 == bits_.end()) {
+        *value = 0;
+        return;
+      }
+      const uint32_t value_l = ((*pos_) << num_used_bits_);
+      num_used_bits_ = nbits - remaining;
+      ++pos_;
+      const uint32_t value_r = (*pos_) >> (32 - num_used_bits_);
+      *value = (value_l >> (32 - num_used_bits_ - remaining)) | value_r;
+    }
+  }
+
+  void EndDecoding() {}
+
+ private:
+  void Clear();
+
+  std::vector<uint32_t> bits_;
+  std::vector<uint32_t>::const_iterator pos_;
+  uint32_t num_used_bits_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_BIT_CODERS_DIRECT_BIT_DECODER_H_