服务端用的四叉树算法

#include <stdlib.h>#include <stdio.h>#include <assert.h>// search_box 时候还需要判断是否有叶子节点。没有的话。则不返回该非叶子节点。// delete #define QUAD_SUB_NODE_COUNT4enum {NE,// 0NW,// 1SW,// 2SE,// 3};bool overlap_box (int v1_minx, int v1_miny, int v1_maxx, int v1_maxy, int v2_minx, int v2_miny, int v2_maxx, int v2_maxy){//return (this->_min._x > rv._max._x || this->_max._x < rv._min._x ||//this->_min._y > rv._max._y || this->_max._y < rv._min._y) ?//false : true;return !(v1_minx > v2_maxx || v1_maxx < v2_minx ||v1_miny >v2_maxy || v1_maxy <v2_miny);// ? false : true;}bool at_point (int v1_minx, int v1_miny, int v1_maxx, int v1_maxy, int v2_minx, int v2_miny, int v2_maxx, int v2_maxy){return (v1_minx == v2_minx && v1_maxx == v2_maxx &&v1_miny == v2_miny && v1_maxy == v2_maxy);}#include <list>struct Node;struct Leaf_Node{Node * _parent;typedefstd::list <void *>List;List data_list;};struct Node{void init (Node * parent){_parent = parent;_leaf_node= 0;_sub[NE] = 0;_sub[NW] = 0;_sub[SW] = 0;_sub[SE] = 0;}void set (int min_x, int min_y, int max_x, int max_y){_min_x = min_x;_min_y = min_y;_max_x = max_x;_max_y = max_y;}bool has_child (){return _sub[NE] != 0;}bool is_sub_empty (){return !(_sub[NE]->_sub[NE] &&//_sub[NE]->_sub[NW] &&//_sub[NE]->_sub[SW] &&//_sub[NE]->_sub[SE] &&_sub[NW]->_sub[NE] &&//_sub[NW]->_sub[NW] &&//_sub[NW]->_sub[SW] &&//_sub[NW]->_sub[SE] &&_sub[SW]->_sub[NE] &&//_sub[SW]->_sub[NW] &&//_sub[SW]->_sub[SW] &&//_sub[SW]->_sub[SE] &&_sub[SE]->_sub[NE] //&&//_sub[SE]->_sub[NW] &&//_sub[SE]->_sub[SW] &&//_sub[SE]->_sub[SE] );}void create_child (){_sub[NE] = (Node *) malloc (sizeof Node);_sub[NW] = (Node *) malloc (sizeof Node);_sub[SW] = (Node *) malloc (sizeof Node);_sub[SE] = (Node *) malloc (sizeof Node);_sub[NE]->init (this);_sub[NW]->init (this);_sub[SW]->init (this);_sub[SE]->init (this);_sub[NE]->_index_in_parent = NE;_sub[NW]->_index_in_parent = NW;_sub[SW]->_index_in_parent = SW;_sub[SE]->_index_in_parent = SE;int center_x = (_max_x + _min_x) >> 1;/// 2;int center_y = (_max_y + _min_y) >> 1;/// 2;_sub[NE]->set (center_x, center_y,_max_x, _max_y);_sub[NW]->set (_min_x, center_y,center_x, _max_y);_sub[SW]->set (_min_x, _min_y,center_x, center_y);_sub[SE]->set (center_x, _min_y,_max_x, center_y);}Node* _sub[QUAD_SUB_NODE_COUNT];Node* _parent;int_index_in_parent;Leaf_Node* _leaf_node;int_min_x;int_min_y;int_max_x;int_max_y;//intx;//inty;};// 回调typedefint (* search_box_callback) (Node * node);class Quadtree{public:Quadtree (){_root = 0;_depth = 6;}// 初始化 四叉树大小void init (int width, int height){_width = width;_height = height;_root = (Node *) malloc (sizeof Node);_root->init (0);_root->set (0, 0, width, height);}//　递归销毁void destroy (Node * curr_node){if (curr_node) {if (curr_node->has_child()) {destroy (curr_node->_sub[NE]);destroy (curr_node->_sub[NW]);destroy (curr_node->_sub[SW]);destroy (curr_node->_sub[SE]);}free (curr_node);}}// 在x， y上插入四叉树void insert (int x, int y){assert (x <= _width && y <=_height);//int deep = 5;_insert (_root, x, y, 0, 0, _width, _height, _depth);}// 判断点在哪个象限，然后再往那个象限细分。void _insert (Node * curr_node, int x, int y, int min_x, int min_y, int max_x, int max_y, int deep){if (deep <= 0) {// 到了最深层了。该结束了。if (x >= min_x && x <= max_x && y >= min_y && y <= max_y) {printf ("add leaf: (%d,%d) (%d,%d)/n", min_x, min_y, max_x, max_y);if (!curr_node->_leaf_node) {Leaf_Node * leaf = new Leaf_Node;leaf->_parent = curr_node;curr_node->_leaf_node = leaf;}}return;}if (! curr_node->has_child ()) {curr_node->create_child ();}int center_x = (max_x + min_x) >> 1;// / 2;int center_y = (max_y + min_y) >> 1;// / 2;if (x < center_x) {if (y < center_y) {// 设置子节点//curr_node->_sub[SW]->set (min_x, min_y, center_x, center_y);//_insert (curr_node->_sub[SW], x, y, //min_x, min_y, center_x, center_y, -- deep);_insert (curr_node->_sub[SW], x, y, curr_node->_sub[SW]->_min_x, curr_node->_sub[SW]->_min_y, curr_node->_sub[SW]->_max_x, curr_node->_sub[SW]->_max_y, -- deep);printf ("insert SW sub node: (%d, %d), (%d, %d)/n",min_x, min_y, center_x, center_y);}else {//curr_node->_sub[NW]->set (min_x, center_y, center_x, max_y);//_insert (curr_node->_sub[NW], x, y,//min_x, center_y, center_x, max_y, -- deep);_insert (curr_node->_sub[NW], x, y,curr_node->_sub[NW]->_min_x, curr_node->_sub[NW]->_min_y, curr_node->_sub[NW]->_max_x, curr_node->_sub[NW]->_max_y, -- deep);printf ("insert NW sub node: (%d, %d), (%d, %d)/n",min_x, center_y, center_x, max_y);}}else {if (y < center_y) {//curr_node->_sub[SE]->set (center_x, min_y, max_x, center_y);//_insert (curr_node->_sub[SE], x, y,//center_x, min_y, max_x, center_y, -- deep);_insert (curr_node->_sub[SE], x, y,curr_node->_sub[SE]->_min_x, curr_node->_sub[SE]->_min_y, curr_node->_sub[SE]->_max_x, curr_node->_sub[SE]->_max_y, -- deep);printf ("insert SE sub node: (%d, %d), (%d, %d)/n",center_x, min_y, max_x, center_y);}else {//curr_node->_sub[NE]->set (center_x, center_y, max_x, max_y);//_insert (curr_node->_sub[NE], x, y,//center_x, center_y, max_x, max_y, -- deep);_insert (curr_node->_sub[NE], x, y,curr_node->_sub[NE]->_min_x, curr_node->_sub[NE]->_min_y, curr_node->_sub[NE]->_max_x, curr_node->_sub[NE]->_max_y,-- deep);printf ("insert NE sub node: (%d, %d), (%d, %d)/n",center_x, center_y, max_x, max_y);}}}// 搜索的次数还是太多。当一个空节点的时候。void search_box (int x, int y, int dx, int dy, search_box_callback cb){_search_box (_root, /*x, y,*/ x-dx, y-dy, x+dx, y+dy, cb);}void _search_box (Node * node, /*int x, int y,*/ int min_x, int min_y, int max_x, int max_y, search_box_callback cb){printf ("search_box/n");if (overlap_box (min_x, min_y, max_x, max_y, node->_min_x, node->_min_y, node->_max_x, node->_max_y)) {if (node->has_child()) {_search_box (node->_sub[NE], /*x, y,*/ min_x, min_y, max_x, max_y, cb);_search_box (node->_sub[NW],/* x, y,*/ min_x, min_y, max_x, max_y, cb);_search_box (node->_sub[SW], /*x, y,*/ min_x, min_y, max_x, max_y, cb);_search_box (node->_sub[SE], /*x, y,*/ min_x, min_y, max_x, max_y, cb);}// 不再有子节点。说明已经是叶子了。可以返回给上一层了。else {if (node->_leaf_node) {printf ("search_box finded: ");cb (node);}}}}void search_line (int x, int y, int end_x, int end_y, search_box_callback cb){int min_x = x < end_x ? x: end_x;intmin_y = y < end_y ? y: end_y;intmax_x = x > end_x ? x : end_x;intmax_y = y > end_y ? y : end_y;// 斜率float h = ((float) max_y - (float)min_y) / ((float)max_x - (float)min_x);_search_line (_root, h, x, y, min_x, min_y, max_x, max_y, cb);}void _search_line (Node * curr_node, float h, int x, int y,// x, y, h用来算一个点在不在一个直线上int min_x, int min_y, int max_x, int max_y, search_box_callback cb){printf ("search_line/n");if (overlap_box (min_x, min_y, max_x, max_y, curr_node->_min_x, curr_node->_min_y, curr_node->_max_x, curr_node->_max_y)) {if (curr_node->has_child()) {_search_line (curr_node->_sub[NE], h, x, y, min_x, min_y, max_x, max_y, cb);_search_line (curr_node->_sub[NW], h, x, y, min_x, min_y, max_x, max_y, cb);_search_line (curr_node->_sub[SW], h, x, y, min_x, min_y, max_x, max_y, cb);_search_line (curr_node->_sub[SE], h, x, y, min_x, min_y, max_x, max_y, cb);}// 不再有子节点。说明已经是叶子了。可以返回给上一层了。else {// 是否在直线内，并且有叶子节点if (abs((float)(curr_node->_min_y) - (float)y - ((float)(curr_node->_min_x) - (float)x) * h) < 0.01f) {if (curr_node->_leaf_node) {printf ("search_line finded: ");cb (curr_node);}}}}}void _delete_empty_node (Node * node){printf ("_delete_empty_node/n");if (_root == node) {return;}// 上一层的其他子节点没有叶子了。if (!(node->_parent->_sub[NE]->_leaf_node || node->_parent->_sub[NW]->_leaf_node|| node->_parent->_sub[SW]->_leaf_node || node->_parent->_sub[SE]->_leaf_node)) {Node * parent = node->_parent;free (parent->_sub[NE]);free (parent->_sub[NW]);free (parent->_sub[SW]);free (parent->_sub[SE]);parent->_sub[NE] = 0;parent->_sub[NW] = 0;parent->_sub[SW] = 0;parent->_sub[SE] = 0;_delete_empty_node (parent);}}void delete_node (Leaf_Node * leaf/*, Node * curr_node*/){Node * in_node = leaf->_parent;in_node->_leaf_node = 0;delete leaf;_delete_empty_node (in_node);}Node * get_node (int x, int y){return _search (x, y, x+1, y+1, _root);}// 搜索的次数还是太多。当一个空节点的时候。Node * _search (int min_x, int min_y, int max_x, int max_y, Node * curr_node){printf ("_search() /n");if (overlap_box (min_x, min_y, max_x, max_y, curr_node->_min_x, curr_node->_min_y, curr_node->_max_x, curr_node->_max_y)) {if (curr_node->_leaf_node) {if (at_point (min_x, min_y, max_x, max_y,curr_node->_min_x, curr_node->_min_y,curr_node->_max_x, curr_node->_max_y)) {printf ("find! %d %d/n", min_x, min_y);return curr_node;}}if (curr_node->has_child()) {printf ("serach :(%d,%d):(%d,%d)/n", min_x, min_y, max_x, max_y); for (int i = 0; i < QUAD_SUB_NODE_COUNT; i ++) {Node * ret = _search(min_x, min_y, max_x, max_y, curr_node->_sub[i]);if (ret) {return ret;}}}}return0;}// 递归打印void dump (Node * node, int deep = 0){if (node) {for (int i = 0; i < deep; i ++) {printf ("+");}printf ("minx: %d, miny: %d, maxx: %d, maxy: %d/n", node->_min_x, node->_min_y, node->_max_x, node->_max_y);if (node->has_child()) {dump (node->_sub[NE], ++deep);dump (node->_sub[NW], deep);dump (node->_sub[SW], deep);dump (node->_sub[SE], deep);}}}// 获取rootNode * root (){return_root;}protected:Node* _root;int_width;int_height;int_depth;};