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- Improved compression for triangular meshes (~10%) - Added WebAssembly decoder - Code cleanup + robustness fixes
56 lines
1.7 KiB
C++
56 lines
1.7 KiB
C++
// Copyright 2016 The Draco Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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#ifndef DRACO_CORE_VARINT_DECODING_H_
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#define DRACO_CORE_VARINT_DECODING_H_
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#include <type_traits>
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#include "core/decoder_buffer.h"
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#include "core/symbol_decoding.h"
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namespace draco {
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// Decodes a specified integer as varint. Note that the IntTypeT must be the
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// same as the one used in the corresponding EncodeVarint() call.
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template <typename IntTypeT>
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void DecodeVarint(IntTypeT *out_val, DecoderBuffer *buffer) {
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if (std::is_unsigned<IntTypeT>::value) {
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// Coding of unsigned values.
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// 0-6 bit - data
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// 7 bit - next byte?
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uint8_t in;
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buffer->Decode(&in);
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if (in & (1 << 7)) {
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// Next byte is available, decode it first.
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DecodeVarint<IntTypeT>(out_val, buffer);
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// Append decoded info from this byte.
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*out_val <<= 7;
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*out_val |= in & ((1 << 7) - 1);
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} else {
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// Last byte reached
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*out_val = in;
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}
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} else {
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// IntTypeT is a signed value. Decode the symbol and convert to signed.
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typename std::make_unsigned<IntTypeT>::type symbol;
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DecodeVarint(&symbol, buffer);
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*out_val = ConvertSymbolToSignedInt(symbol);
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}
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}
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} // namespace draco
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#endif // DRACO_CORE_VARINT_DECODING_H_
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