godot/core/vmap.h
Hein-Pieter van Braam 0e29f7974b Reduce unnecessary COW on Vector by make writing explicit
This commit makes operator[] on Vector const and adds a write proxy to it.  From
now on writes to Vectors need to happen through the .write proxy. So for
instance:

Vector<int> vec;
vec.push_back(10);
std::cout << vec[0] << std::endl;
vec.write[0] = 20;

Failing to use the .write proxy will cause a compilation error.

In addition COWable datatypes can now embed a CowData pointer to their data.
This means that String, CharString, and VMap no longer use or derive from
Vector.

_ALWAYS_INLINE_ and _FORCE_INLINE_ are now equivalent for debug and non-debug
builds. This is a lot faster for Vector in the editor and while running tests.
The reason why this difference used to exist is because force-inlined methods
used to give a bad debugging experience. After extensive testing with modern
compilers this is no longer the case.
2018-07-26 00:54:16 +02:00

213 lines
5.3 KiB
C++

/*************************************************************************/
/* vmap.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2018 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 VMAP_H
#define VMAP_H
#include "cowdata.h"
#include "typedefs.h"
template <class T, class V>
class VMap {
struct _Pair {
T key;
V value;
_FORCE_INLINE_ _Pair() {}
_FORCE_INLINE_ _Pair(const T &p_key, const V &p_value) {
key = p_key;
value = p_value;
}
};
CowData<_Pair> _cowdata;
_FORCE_INLINE_ int _find(const T &p_val, bool &r_exact) const {
r_exact = false;
if (_cowdata.empty())
return 0;
int low = 0;
int high = _cowdata.size() - 1;
const _Pair *a = _cowdata.ptr();
int middle = 0;
#if DEBUG_ENABLED
if (low > high)
ERR_PRINT("low > high, this may be a bug");
#endif
while (low <= high) {
middle = (low + high) / 2;
if (p_val < a[middle].key) {
high = middle - 1; //search low end of array
} else if (a[middle].key < p_val) {
low = middle + 1; //search high end of array
} else {
r_exact = true;
return middle;
}
}
//return the position where this would be inserted
if (a[middle].key < p_val)
middle++;
return middle;
}
_FORCE_INLINE_ int _find_exact(const T &p_val) const {
if (_cowdata.empty())
return -1;
int low = 0;
int high = _cowdata.size() - 1;
int middle;
const _Pair *a = _cowdata.ptr();
while (low <= high) {
middle = (low + high) / 2;
if (p_val < a[middle].key) {
high = middle - 1; //search low end of array
} else if (a[middle].key < p_val) {
low = middle + 1; //search high end of array
} else {
return middle;
}
}
return -1;
}
public:
int insert(const T &p_key, const V &p_val) {
bool exact;
int pos = _find(p_key, exact);
if (exact) {
_cowdata.get_m(pos).value = p_val;
return pos;
}
_cowdata.insert(pos, _Pair(p_key, p_val));
return pos;
}
bool has(const T &p_val) const {
return _find_exact(p_val) != -1;
}
void erase(const T &p_val) {
int pos = _find_exact(p_val);
if (pos < 0)
return;
_cowdata.remove(pos);
}
int find(const T &p_val) const {
return _find_exact(p_val);
}
int find_nearest(const T &p_val) const {
bool exact;
return _find(p_val, exact);
}
_FORCE_INLINE_ int size() const { return _cowdata.size(); }
_FORCE_INLINE_ bool empty() const { return _cowdata.empty(); }
const _Pair *get_array() const {
return _cowdata.ptr();
}
_Pair *get_array() {
return _cowdata.ptrw();
}
const V &getv(int p_index) const {
return _cowdata.get(p_index).value;
}
V &getv(int p_index) {
return _cowdata.get_m(p_index).value;
}
const T &getk(int p_index) const {
return _cowdata.get(p_index).key;
}
T &getk(int p_index) {
return _cowdata.get_m(p_index).key;
}
inline const V &operator[](const T &p_key) const {
int pos = _find_exact(p_key);
CRASH_COND(pos < 0);
return _cowdata.get(pos).value;
}
inline V &operator[](const T &p_key) {
int pos = _find_exact(p_key);
if (pos < 0) {
V val;
pos = insert(p_key, val);
}
return _cowdata.get_m(pos).value;
}
_FORCE_INLINE_ VMap(){};
_FORCE_INLINE_ VMap(const VMap &p_from) { _cowdata._ref(p_from._cowdata); }
inline VMap &operator=(const VMap &p_from) {
_cowdata._ref(p_from._cowdata);
return *this;
}
};
#endif // VMAP_H