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Differential D4501 Diff 14126 extern/gltf-draco/draco/src/draco/compression/point_cloud/algorithms/integer_points_kd_tree_decoder.h

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extern/gltf-draco/draco/src/draco/compression/point_cloud/algorithms/integer_points_kd_tree_decoder.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.
//
// TODO(hemmer): Make this a wrapper using DynamicIntegerPointsKdTreeDecoder.
//
// See integer_points_kd_tree_encoder.h for documentation.
#ifndef DRACO_COMPRESSION_POINT_CLOUD_ALGORITHMS_INTEGER_POINTS_KD_TREE_DECODER_H_
#define DRACO_COMPRESSION_POINT_CLOUD_ALGORITHMS_INTEGER_POINTS_KD_TREE_DECODER_H_
#include <array>
#include <memory>
#include "draco/compression/bit_coders/adaptive_rans_bit_decoder.h"
#include "draco/compression/bit_coders/direct_bit_decoder.h"
#include "draco/compression/bit_coders/folded_integer_bit_decoder.h"
#include "draco/compression/bit_coders/rans_bit_decoder.h"
#include "draco/compression/point_cloud/algorithms/point_cloud_types.h"
#include "draco/compression/point_cloud/algorithms/queuing_policy.h"
#include "draco/core/bit_utils.h"
#include "draco/core/decoder_buffer.h"
#include "draco/core/math_utils.h"
namespace draco {
template <int compression_level_t>
struct IntegerPointsKdTreeDecoderCompressionPolicy
: public IntegerPointsKdTreeDecoderCompressionPolicy<compression_level_t -
1> {};
template <>
struct IntegerPointsKdTreeDecoderCompressionPolicy<0> {
typedef DirectBitDecoder NumbersDecoder;
typedef DirectBitDecoder AxisDecoder;
typedef DirectBitDecoder HalfDecoder;
typedef DirectBitDecoder RemainingBitsDecoder;
static constexpr bool select_axis = false;
template <class T>
using QueuingStrategy = Stack<T>;
};
template <>
struct IntegerPointsKdTreeDecoderCompressionPolicy<2>
: public IntegerPointsKdTreeDecoderCompressionPolicy<1> {
typedef RAnsBitDecoder NumbersDecoder;
};
template <>
struct IntegerPointsKdTreeDecoderCompressionPolicy<4>
: public IntegerPointsKdTreeDecoderCompressionPolicy<3> {
typedef FoldedBit32Decoder<RAnsBitDecoder> NumbersDecoder;
};
template <>
struct IntegerPointsKdTreeDecoderCompressionPolicy<6>
: public IntegerPointsKdTreeDecoderCompressionPolicy<5> {
static constexpr bool select_axis = true;
};
template <>
struct IntegerPointsKdTreeDecoderCompressionPolicy<8>
: public IntegerPointsKdTreeDecoderCompressionPolicy<7> {
typedef FoldedBit32Decoder<AdaptiveRAnsBitDecoder> NumbersDecoder;
template <class T>
using QueuingStrategy = Queue<T>;
};
template <>
struct IntegerPointsKdTreeDecoderCompressionPolicy<10>
: public IntegerPointsKdTreeDecoderCompressionPolicy<9> {
template <class T>
using QueuingStrategy = PriorityQueue<T>;
};
// Decodes a point cloud encoded by IntegerPointsKdTreeEncoder.
// |PointDiT| is a type representing a point with uint32_t coordinates.
// must provide construction from three uint32_t and operator[].
template <class PointDiT, int compression_level_t>
class IntegerPointsKdTreeDecoder {
typedef IntegerPointsKdTreeDecoderCompressionPolicy<compression_level_t>
Policy;
typedef typename Policy::NumbersDecoder NumbersDecoder;
typedef typename Policy::AxisDecoder AxisDecoder;
typedef typename Policy::HalfDecoder HalfDecoder;
typedef typename Policy::RemainingBitsDecoder RemainingBitsDecoder;
public:
IntegerPointsKdTreeDecoder() : bit_length_(0) {}
// Decodes a integer point cloud from |buffer|.
template <class OutputIteratorT>
bool DecodePoints(DecoderBuffer *buffer, OutputIteratorT oit);
private:
// For the sake of readability of code, we decided to make this exception
// from the naming scheme.
static constexpr int D = PointTraits<PointDiT>::Dimension();
uint32_t GetAxis(uint32_t num_remaining_points, const PointDiT &base,
std::array<uint32_t, D> levels, uint32_t last_axis);
template <class OutputIteratorT>
void DecodeInternal(uint32_t num_remaining_points, PointDiT base,
std::array<uint32_t, D> levels, uint32_t last_axis,
OutputIteratorT oit);
void DecodeNumber(int nbits, uint32_t *value) {
numbers_decoder_.DecodeLeastSignificantBits32(nbits, value);
}
struct DecodingStatus {
DecodingStatus(
uint32_t num_remaining_points_, const PointDiT &old_base_,
std::array<uint32_t, PointTraits<PointDiT>::Dimension()> levels_,
uint32_t last_axis_)
: num_remaining_points(num_remaining_points_),
old_base(old_base_),
levels(levels_),
last_axis(last_axis_) {}
uint32_t num_remaining_points;
PointDiT old_base;
std::array<uint32_t, D> levels;
uint32_t last_axis;
friend bool operator<(const DecodingStatus &l, const DecodingStatus &r) {
return l.num_remaining_points < r.num_remaining_points;
}
};
uint32_t bit_length_;
uint32_t num_points_;
NumbersDecoder numbers_decoder_;
RemainingBitsDecoder remaining_bits_decoder_;
AxisDecoder axis_decoder_;
HalfDecoder half_decoder_;
};
// Decodes a point cloud from |buffer|.
template <class PointDiT, int compression_level_t>
template <class OutputIteratorT>
bool IntegerPointsKdTreeDecoder<PointDiT, compression_level_t>::DecodePoints(
DecoderBuffer *buffer, OutputIteratorT oit) {
buffer->Decode(&bit_length_);
buffer->Decode(&num_points_);
if (num_points_ == 0)
return true;
if (!numbers_decoder_.StartDecoding(buffer))
return false;
if (!remaining_bits_decoder_.StartDecoding(buffer))
return false;
if (!axis_decoder_.StartDecoding(buffer))
return false;
if (!half_decoder_.StartDecoding(buffer))
return false;
DecodeInternal(num_points_, PointTraits<PointDiT>::Origin(),
PointTraits<PointDiT>::ZeroArray(), 0, oit);
numbers_decoder_.EndDecoding();
remaining_bits_decoder_.EndDecoding();
axis_decoder_.EndDecoding();
half_decoder_.EndDecoding();
return true;
}
template <class PointDiT, int compression_level_t>
uint32_t IntegerPointsKdTreeDecoder<PointDiT, compression_level_t>::GetAxis(
uint32_t num_remaining_points, const PointDiT & /* base */,
std::array<uint32_t, D> levels, uint32_t last_axis) {
if (!Policy::select_axis)
return DRACO_INCREMENT_MOD(last_axis, D);
uint32_t best_axis = 0;
if (num_remaining_points < 64) {
for (uint32_t axis = 1; axis < D; ++axis) {
if (levels[best_axis] > levels[axis]) {
best_axis = axis;
}
}
} else {
axis_decoder_.DecodeLeastSignificantBits32(4, &best_axis);
}
return best_axis;
}
template <class PointDiT, int compression_level_t>
template <class OutputIteratorT>
void IntegerPointsKdTreeDecoder<PointDiT, compression_level_t>::DecodeInternal(
uint32_t num_remaining_points, PointDiT old_base,
std::array<uint32_t, D> levels, uint32_t last_axis, OutputIteratorT oit) {
DecodingStatus init_status(num_remaining_points, old_base, levels, last_axis);
typename Policy::template QueuingStrategy<DecodingStatus> status_q;
status_q.push(init_status);
while (!status_q.empty()) {
const DecodingStatus status = status_q.front();
status_q.pop();
num_remaining_points = status.num_remaining_points;
old_base = status.old_base;
levels = status.levels;
last_axis = status.last_axis;
const uint32_t axis =
GetAxis(num_remaining_points, old_base, levels, last_axis);
const uint32_t level = levels[axis];
// All axes have been fully subdivided, just output points.
if ((bit_length_ - level) == 0) {
for (int i = 0; i < static_cast<int>(num_remaining_points); i++) {
*oit++ = old_base;
}
continue;
}
DRACO_DCHECK_EQ(true, num_remaining_points != 0);
if (num_remaining_points <= 2) {
std::array<uint32_t, D> axes;
axes[0] = axis;
for (int i = 1; i < D; i++) {
axes[i] = DRACO_INCREMENT_MOD(axes[i - 1], D);
}
std::array<uint32_t, D> num_remaining_bits;
for (int i = 0; i < D; i++) {
num_remaining_bits[i] = bit_length_ - levels[axes[i]];
}
for (uint32_t i = 0; i < num_remaining_points; ++i) {
// Get remaining bits, mind the carry if not starting at x.
PointDiT p = PointTraits<PointDiT>::Origin();
for (int j = 0; j < static_cast<int>(D); j++) {
if (num_remaining_bits[j])
remaining_bits_decoder_.DecodeLeastSignificantBits32(
num_remaining_bits[j], &p[axes[j]]);
p[axes[j]] = old_base[axes[j]] | p[axes[j]];
}
*oit++ = p;
}
continue;
}
const int num_remaining_bits = bit_length_ - level;
const uint32_t modifier = 1 << (num_remaining_bits - 1);
PointDiT new_base(old_base);
new_base[axis] += modifier;
const int incoming_bits = MostSignificantBit(num_remaining_points);
uint32_t number = 0;
DecodeNumber(incoming_bits, &number);
uint32_t first_half = num_remaining_points / 2 - number;
uint32_t second_half = num_remaining_points - first_half;
if (first_half != second_half)
if (!half_decoder_.DecodeNextBit())
std::swap(first_half, second_half);
levels[axis] += 1;
if (first_half)
status_q.push(DecodingStatus(first_half, old_base, levels, axis));
if (second_half)
status_q.push(DecodingStatus(second_half, new_base, levels, axis));
}
}
extern template class IntegerPointsKdTreeDecoder<Point3ui, 0>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 1>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 2>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 3>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 4>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 5>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 6>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 7>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 8>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 9>;
extern template class IntegerPointsKdTreeDecoder<Point3ui, 10>;
} // namespace draco
#endif // DRACO_COMPRESSION_POINT_CLOUD_ALGORITHMS_INTEGER_POINTS_KD_TREE_DECODER_H_