PreVerify/lib/opencv480/include/opencv2/flann/dynamic_bitset.h
2024-09-09 19:18:28 +08:00

164 lines
4.5 KiB
C++

/***********************************************************************
* Software License Agreement (BSD License)
*
* Copyright 2008-2009 Marius Muja (mariusm@cs.ubc.ca). All rights reserved.
* Copyright 2008-2009 David G. Lowe (lowe@cs.ubc.ca). All rights reserved.
*
* THE BSD LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*************************************************************************/
/***********************************************************************
* Author: Vincent Rabaud
*************************************************************************/
#ifndef OPENCV_FLANN_DYNAMIC_BITSET_H_
#define OPENCV_FLANN_DYNAMIC_BITSET_H_
//! @cond IGNORED
#ifndef FLANN_USE_BOOST
# define FLANN_USE_BOOST 0
#endif
//#define FLANN_USE_BOOST 1
#if FLANN_USE_BOOST
#include <boost/dynamic_bitset.hpp>
typedef boost::dynamic_bitset<> DynamicBitset;
#else
#include <limits.h>
#include "dist.h"
namespace cvflann {
/** Class re-implementing the boost version of it
* This helps not depending on boost, it also does not do the bound checks
* and has a way to reset a block for speed
*/
class DynamicBitset
{
public:
/** default constructor
*/
DynamicBitset() : size_(0)
{
}
/** only constructor we use in our code
* @param sz the size of the bitset (in bits)
*/
DynamicBitset(size_t sz)
{
resize(sz);
reset();
}
/** Sets all the bits to 0
*/
void clear()
{
std::fill(bitset_.begin(), bitset_.end(), 0);
}
/** @brief checks if the bitset is empty
* @return true if the bitset is empty
*/
bool empty() const
{
return bitset_.empty();
}
/** set all the bits to 0
*/
void reset()
{
std::fill(bitset_.begin(), bitset_.end(), 0);
}
/** @brief set one bit to 0
* @param index
*/
void reset(size_t index)
{
bitset_[index / cell_bit_size_] &= ~(size_t(1) << (index % cell_bit_size_));
}
/** @brief sets a specific bit to 0, and more bits too
* This function is useful when resetting a given set of bits so that the
* whole bitset ends up being 0: if that's the case, we don't care about setting
* other bits to 0
* @param index
*/
void reset_block(size_t index)
{
bitset_[index / cell_bit_size_] = 0;
}
/** resize the bitset so that it contains at least sz bits
* @param sz
*/
void resize(size_t sz)
{
size_ = sz;
bitset_.resize(sz / cell_bit_size_ + 1);
}
/** set a bit to true
* @param index the index of the bit to set to 1
*/
void set(size_t index)
{
bitset_[index / cell_bit_size_] |= size_t(1) << (index % cell_bit_size_);
}
/** gives the number of contained bits
*/
size_t size() const
{
return size_;
}
/** check if a bit is set
* @param index the index of the bit to check
* @return true if the bit is set
*/
bool test(size_t index) const
{
return (bitset_[index / cell_bit_size_] & (size_t(1) << (index % cell_bit_size_))) != 0;
}
private:
std::vector<size_t> bitset_;
size_t size_;
static const unsigned int cell_bit_size_ = CHAR_BIT * sizeof(size_t);
};
} // namespace cvflann
#endif
//! @endcond
#endif // OPENCV_FLANN_DYNAMIC_BITSET_H_