godot/core/set.h
Rémi Verschelde c7bc44d5ad Welcome in 2017, dear changelog reader!
That year should bring the long-awaited OpenGL ES 3.0 compatible renderer
with state-of-the-art rendering techniques tuned to work as low as middle
end handheld devices - without compromising with the possibilities given
for higher end desktop games of course. Great times ahead for the Godot
community and the gamers that will play our games!
2017-01-01 22:03:33 +01:00

667 lines
14 KiB
C++

/*************************************************************************/
/* set.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* */
/* 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 SET_H
#define SET_H
#include "typedefs.h"
#include "os/memory.h"
/**
@author Juan Linietsky <reduzio@gmail.com>
*/
// based on the very nice implementation of rb-trees by:
// http://web.mit.edu/~emin/www/source_code/red_black_tree/index.html
template <class T,class C=Comparator<T>,class A=DefaultAllocator >
class Set {
enum Color {
RED,
BLACK
};
struct _Data;
public:
class Element {
private:
friend class Set<T,C,A>;
int color;
Element* right;
Element* left;
Element* parent;
Element* _next;
Element* _prev;
T value;
//_Data *data;
public:
const Element *next() const {
return _next;
}
Element *next() {
return _next;
}
const Element *prev() const {
return _prev;
}
Element *prev() {
return _prev;
}
const T& get() const {
return value;
};
Element() {
color=RED;
right=NULL;
left=NULL;
parent=NULL;
_next=NULL;
_prev=NULL;
};
};
private:
struct _Data {
Element* _root;
Element* _nil;
int size_cache;
_Data() {
#ifdef GLOBALNIL_DISABLED
_nil = memnew_allocator( Element,A );
_nil->parent=_nil->left=_nil->right=_nil;
_nil->color=BLACK;
#else
_nil=(Element*)&_GlobalNilClass::_nil;
#endif
_root = NULL;
size_cache=0;
}
void _create_root() {
_root = memnew_allocator( Element,A );
_root->parent=_root->left=_root->right=_nil;
_root->color=BLACK;
}
void _free_root() {
if (_root) {
memdelete_allocator<Element,A>(_root);
_root=NULL;
}
}
~_Data() {
_free_root();
#ifdef GLOBALNIL_DISABLED
memdelete_allocator<Element,A>(_nil);
#endif
// memdelete_allocator<Element,A>(_root);
}
};
_Data _data;
inline void _set_color(Element *p_node, int p_color) {
ERR_FAIL_COND( p_node == _data._nil && p_color == RED );
p_node->color=p_color;
}
inline void _rotate_left(Element *p_node) {
Element *r=p_node->right;
p_node->right=r->left;
if (r->left != _data._nil )
r->left->parent=p_node;
r->parent=p_node->parent;
if (p_node==p_node->parent->left)
p_node->parent->left=r;
else
p_node->parent->right=r;
r->left=p_node;
p_node->parent=r;
}
inline void _rotate_right(Element *p_node) {
Element *l=p_node->left;
p_node->left=l->right;
if (l->right != _data._nil)
l->right->parent=p_node;
l->parent=p_node->parent;
if (p_node==p_node->parent->right)
p_node->parent->right=l;
else
p_node->parent->left=l;
l->right=p_node;
p_node->parent=l;
}
inline Element* _successor(Element *p_node) const {
Element *node=p_node;
if (node->right != _data._nil) {
node=node->right;
while(node->left != _data._nil) { /* returns the minium of the right subtree of node */
node=node->left;
}
return node;
} else {
while(node == node->parent->right) {
node=node->parent;
}
if (node->parent == _data._root)
return NULL;
return node->parent;
}
}
inline Element* _predecessor(Element *p_node) const {
Element *node=p_node;
if (node->left != _data._nil) {
node=node->left;
while(node->right != _data._nil) { /* returns the minium of the left subtree of node */
node=node->right;
}
return node;
} else {
while(node == node->parent->left) {
if (node->parent == _data._root)
return NULL;
node=node->parent;
}
return node->parent;
}
}
Element *_find(const T& p_value) const {
Element *node = _data._root->left;
C less;
while(node!=_data._nil) {
if (less(p_value,node->value))
node=node->left;
else if (less(node->value,p_value))
node=node->right;
else
break; // found
}
return (node!=_data._nil)?node:NULL;
}
Element *_lower_bound(const T& p_value) const {
Element *node = _data._root->left;
Element *prev = NULL;
C less;
while(node!=_data._nil) {
prev=node;
if (less(p_value,node->value))
node=node->left;
else if (less(node->value,p_value))
node=node->right;
else
break; // found
}
if (node==_data._nil) {
if (prev==NULL)
return NULL;
if (less(prev->value,p_value)) {
prev=prev->_next;
}
return prev;
} else
return node;
}
Element *_insert(const T& p_value, bool& r_exists) {
Element *new_parent=_data._root;
Element *node = _data._root->left;
C less;
while (node!=_data._nil) {
new_parent=node;
if (less(p_value,node->value))
node=node->left;
else if (less(node->value,p_value))
node=node->right;
else {
r_exists=true;
return node;
}
}
Element *new_node = memnew_allocator( Element,A );
new_node->parent=new_parent;
new_node->right=_data._nil;
new_node->left=_data._nil;
new_node->value=p_value;
// new_node->data=_data;
if (new_parent==_data._root || less(p_value,new_parent->value)) {
new_parent->left=new_node;
} else {
new_parent->right=new_node;
}
r_exists=false;
new_node->_next=_successor(new_node);
new_node->_prev=_predecessor(new_node);
if (new_node->_next)
new_node->_next->_prev=new_node;
if (new_node->_prev)
new_node->_prev->_next=new_node;
return new_node;
}
Element * _insert_rb(const T& p_value) {
bool exists=false;
Element *new_node = _insert(p_value,exists);
if (exists)
return new_node;
Element *node=new_node;
_data.size_cache++;
while(node->parent->color==RED) {
if (node->parent == node->parent->parent->left) {
Element *aux=node->parent->parent->right;
if (aux->color==RED) {
_set_color(node->parent,BLACK);
_set_color(aux,BLACK);
_set_color(node->parent->parent,RED);
node=node->parent->parent;
} else {
if (node == node->parent->right) {
node=node->parent;
_rotate_left(node);
}
_set_color(node->parent,BLACK);
_set_color(node->parent->parent,RED);
_rotate_right(node->parent->parent);
}
} else {
Element *aux=node->parent->parent->left;
if (aux->color==RED) {
_set_color(node->parent,BLACK);
_set_color(aux,BLACK);
_set_color(node->parent->parent,RED);
node=node->parent->parent;
} else {
if (node == node->parent->left) {
node=node->parent;
_rotate_right(node);
}
_set_color(node->parent,BLACK);
_set_color(node->parent->parent,RED);
_rotate_left(node->parent->parent);
}
}
}
_set_color(_data._root->left,BLACK);
return new_node;
}
void _erase_fix(Element *p_node) {
Element *root = _data._root->left;
Element *node=p_node;
while( (node->color==BLACK) && (root != node)) {
if (node == node->parent->left) {
Element *aux=node->parent->right;
if (aux->color==RED) {
_set_color(aux,BLACK);
_set_color(node->parent,RED);
_rotate_left(node->parent);
aux=node->parent->right;
}
if ( (aux->right->color==BLACK) && (aux->left->color==BLACK) ) {
_set_color(aux,RED);
node=node->parent;
} else {
if (aux->right->color==BLACK) {
_set_color(aux->left,BLACK);
_set_color(aux,RED);
_rotate_right(aux);
aux=node->parent->right;
}
_set_color(aux,node->parent->color);
_set_color(node->parent,BLACK);
_set_color(aux->right,BLACK);
_rotate_left(node->parent);
node=root; /* this is to exit while loop */
}
} else { /* the code below is has left and right switched from above */
Element *aux=node->parent->left;
if (aux->color==RED) {
_set_color(aux,BLACK);
_set_color(node->parent,RED);;
_rotate_right(node->parent);
aux=node->parent->left;
}
if ( (aux->right->color==BLACK) && (aux->left->color==BLACK) ) {
_set_color(aux,RED);
node=node->parent;
} else {
if (aux->left->color==BLACK) {
_set_color(aux->right,BLACK);
_set_color(aux,RED);
_rotate_left(aux);
aux=node->parent->left;
}
_set_color(aux,node->parent->color);
_set_color(node->parent,BLACK);
_set_color(aux->left,BLACK);
_rotate_right(node->parent);
node=root;
}
}
}
_set_color(node,BLACK);
ERR_FAIL_COND(_data._nil->color!=BLACK);
}
void _erase(Element *p_node) {
Element *rp= ((p_node->left == _data._nil) || (p_node->right == _data._nil)) ? p_node : _successor(p_node);
if (!rp)
rp=_data._nil;
Element *node= (rp->left == _data._nil) ? rp->right : rp->left;
if (_data._root == (node->parent=rp->parent) ) {
_data._root->left=node;
} else {
if (rp == rp->parent->left) {
rp->parent->left=node;
} else {
rp->parent->right=node;
}
}
if (rp != p_node) {
ERR_FAIL_COND( rp == _data._nil );
if (rp->color==BLACK)
_erase_fix(node);
rp->left=p_node->left;
rp->right=p_node->right;
rp->parent=p_node->parent;
rp->color=p_node->color;
p_node->left->parent=rp;
p_node->right->parent=rp;
if (p_node == p_node->parent->left) {
p_node->parent->left=rp;
} else {
p_node->parent->right=rp;
}
} else {
if (p_node->color==BLACK)
_erase_fix(node);
}
if (p_node->_next)
p_node->_next->_prev=p_node->_prev;
if (p_node->_prev)
p_node->_prev->_next=p_node->_next;
memdelete_allocator<Element,A>(p_node);
_data.size_cache--;
ERR_FAIL_COND( _data._nil->color==RED );
}
void _calculate_depth(Element *p_element,int &max_d,int d) const {
if (p_element==_data._nil) {
return;
}
_calculate_depth(p_element->left,max_d,d+1);
_calculate_depth(p_element->right,max_d,d+1);
if (d>max_d)
max_d=d;
}
void _cleanup_tree(Element *p_element) {
if (p_element==_data._nil)
return;
_cleanup_tree(p_element->left);
_cleanup_tree(p_element->right);
memdelete_allocator<Element,A>( p_element );
}
void _copy_from( const Set& p_set) {
clear();
// not the fastest way, but safeset to write.
for(Element *I=p_set.front();I;I=I->next()) {
insert(I->get());
}
}
public:
const Element *find(const T& p_value) const {
if (!_data._root)
return NULL;
const Element *res=_find(p_value);
return res;
}
Element *find(const T& p_value) {
if (!_data._root)
return NULL;
Element *res=_find(p_value);
return res;
}
bool has(const T& p_value) const {
if (!_data._root)
return false;
return find(p_value)!=NULL;
}
Element *insert(const T& p_value) {
if (!_data._root)
_data._create_root();
return _insert_rb(p_value);
}
void erase(Element* p_element) {
if (!_data._root)
return;
_erase(p_element);
if (_data.size_cache==0 && _data._root)
_data._free_root();
}
bool erase(const T& p_value) {
if (!_data._root)
return false;
Element *e=find(p_value);
if (!e)
return false;
_erase(e);
if (_data.size_cache==0 && _data._root)
_data._free_root();
return true;
}
Element *front() const {
if (!_data._root)
return NULL;
Element *e=_data._root->left;
if (e==_data._nil)
return NULL;
while(e->left!=_data._nil)
e=e->left;
return e;
}
Element *back() const {
if (!_data._root)
return NULL;
Element *e=_data._root->left;
if (e==_data._nil)
return NULL;
while(e->right!=_data._nil)
e=e->right;
return e;
}
Element *lower_bound(const T& p_value) const {
return _lower_bound(p_value);
}
inline int size() const { return _data.size_cache; }
int calculate_depth() const {
// used for debug mostly
if (!_data._root)
return 0;
int max_d=0;
_calculate_depth(_data._root->left,max_d,0);
return max_d;
}
void clear() {
if (!_data._root)
return;
_cleanup_tree(_data._root->left);
_data._root->left=_data._nil;
_data.size_cache=0;
_data._nil->parent=_data._nil;
_data._free_root();
}
void operator=(const Set& p_set) {
_copy_from( p_set );
}
Set(const Set& p_set) {
_copy_from( p_set );
}
_FORCE_INLINE_ Set() {
}
~Set() {
clear();
}
};
#endif