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73bb3c8530
- Improved compression for triangular meshes (~10%) - Added WebAssembly decoder - Code cleanup + robustness fixes
59 lines
2.2 KiB
C++
59 lines
2.2 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_SYMBOL_ENCODING_H_
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#define DRACO_CORE_SYMBOL_ENCODING_H_
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#include <type_traits>
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#include "core/encoder_buffer.h"
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namespace draco {
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// Helper function that converts signed integer values into unsigned integer
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// symbols that can be encoded using an entropy encoder.
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void ConvertSignedIntsToSymbols(const int32_t *in, int in_values,
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uint32_t *out);
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// Helper function that converts a single signed integer value into an unsigned
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// integer symbol that can be encoded using an entropy encoder.
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template <class IntTypeT>
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typename std::make_unsigned<IntTypeT>::type ConvertSignedIntToSymbol(
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IntTypeT val) {
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typedef typename std::make_unsigned<IntTypeT>::type UnsignedType;
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static_assert(std::is_integral<IntTypeT>::value, "IntTypeT is not integral.");
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// Early exit if val is positive.
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if (val >= 0) {
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return static_cast<UnsignedType>(val) << 1;
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}
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val = -(val + 1); // Map -1 to 0, -2 to -1, etc..
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UnsignedType ret = static_cast<UnsignedType>(val);
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ret <<= 1;
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ret |= 1;
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return ret;
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}
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// Encodes an array of symbols using an entropy coding. This function
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// automatically decides whether to encode the symbol values using using bit
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// length tags (see EncodeTaggedSymbols), or whether to encode them directly
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// (see EncodeRawSymbols). The symbols can be grouped into separate components
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// that can be used for better compression.
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// Returns false on error.
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bool EncodeSymbols(const uint32_t *symbols, int num_values, int num_components,
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EncoderBuffer *target_buffer);
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} // namespace draco
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#endif // DRACO_CORE_SYMBOL_ENCODING_H_
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