godot/core/bitfield_dynamic.h

112 lines
4.2 KiB
C++

/*************************************************************************/
/* bitfield_dynamic.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#ifndef BITFIELD_DYNAMIC_H
#define BITFIELD_DYNAMIC_H
#include "core/error_macros.h"
class BitFieldDynamic {
public:
~BitFieldDynamic() { destroy(); }
private:
// prevent copying (see effective C++ scott meyers)
// there is no implementation for copy constructor, hence compiler will complain if you try to copy
// feel free to add one if needed...
BitFieldDynamic &operator=(const BitFieldDynamic &);
public:
// create automatically blanks
void create(uint32_t p_num_bits, bool p_blank = true);
void destroy();
// public funcs
uint32_t get_num_bits() const { return _num_bits; }
uint32_t get_bit(uint32_t p_bit) const;
void set_bit(uint32_t p_bit, uint32_t p_set);
bool check_and_set(uint32_t p_bit);
void blank(bool p_set_or_zero = false);
void invert();
void copy_from(const BitFieldDynamic &p_source);
// loading / saving
uint8_t *get_data() { return _data; }
const uint8_t *get_data() const { return _data; }
uint32_t get_num_bytes() const { return _num_bytes; }
protected:
// member vars
uint8_t *_data = nullptr;
uint32_t _num_bytes = 0;
uint32_t _num_bits = 0;
};
inline uint32_t BitFieldDynamic::get_bit(uint32_t p_bit) const {
DEV_ASSERT(_data);
uint32_t byte_number = p_bit >> 3; // divide by 8
DEV_ASSERT(byte_number < _num_bytes);
uint8_t uc = _data[byte_number];
uint32_t bit_set = uc & (1 << (p_bit & 7));
return bit_set;
}
inline bool BitFieldDynamic::check_and_set(uint32_t p_bit) {
DEV_ASSERT(_data);
uint32_t byte_number = p_bit >> 3; // divide by 8
DEV_ASSERT(byte_number < _num_bytes);
uint8_t &uc = _data[byte_number];
uint32_t mask = (1 << (p_bit & 7));
uint32_t bit_set = uc & mask;
if (bit_set) {
return false;
}
// set
uc = uc | mask;
return true;
}
inline void BitFieldDynamic::set_bit(uint32_t p_bit, uint32_t p_set) {
DEV_ASSERT(_data);
uint32_t byte_number = p_bit >> 3; // divide by 8
DEV_ASSERT(byte_number < _num_bytes);
uint8_t uc = _data[byte_number];
uint32_t mask = 1 << (p_bit & 7);
if (p_set) {
uc = uc | mask;
} else {
uc &= ~mask;
}
_data[byte_number] = uc;
}
#endif