300 lines
7.8 KiB
C++
300 lines
7.8 KiB
C++
/*****************************************************************************
|
|
*
|
|
* This file is part of Mapnik (c++ mapping toolkit)
|
|
*
|
|
* Copyright (C) 2006 Artem Pavlenko
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*
|
|
*****************************************************************************/
|
|
//$Id: quadtree.hh 17 2005-03-08 23:58:43Z pavlenko $
|
|
|
|
#ifndef QUADTREE_HPP
|
|
#define QUADTREE_HPP
|
|
// stl
|
|
#include <cstring>
|
|
#include <vector>
|
|
#include <fstream>
|
|
#include <iostream>
|
|
// mapnik
|
|
#include <mapnik/box2d.hpp>
|
|
|
|
using mapnik::box2d;
|
|
using mapnik::coord2d;
|
|
|
|
template <typename T>
|
|
struct quadtree_node
|
|
{
|
|
box2d<double> ext_;
|
|
std::vector<T> data_;
|
|
quadtree_node<T>* children_[4];
|
|
quadtree_node(const box2d<double>& ext)
|
|
: ext_(ext),data_()
|
|
{
|
|
memset(children_,0,sizeof(quadtree_node<T>*)*4);
|
|
}
|
|
|
|
~quadtree_node()
|
|
{
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
if (children_[i])
|
|
{
|
|
delete children_[i],children_[i]=0;
|
|
}
|
|
}
|
|
}
|
|
|
|
int num_subnodes() const
|
|
{
|
|
int count=0;
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
if (children_[i])
|
|
{
|
|
++count;
|
|
}
|
|
}
|
|
return count;
|
|
}
|
|
};
|
|
|
|
template <typename T>
|
|
class quadtree
|
|
{
|
|
private:
|
|
quadtree_node<T>* root_;
|
|
const int maxdepth_;
|
|
const double ratio_;
|
|
public:
|
|
quadtree(const box2d<double>& extent,int maxdepth,double ratio)
|
|
: root_(new quadtree_node<T>(extent)),
|
|
maxdepth_(maxdepth),
|
|
ratio_(ratio) {}
|
|
|
|
~quadtree()
|
|
{
|
|
if (root_) delete root_;
|
|
}
|
|
|
|
void insert(const T& data,const box2d<double>& item_ext)
|
|
{
|
|
insert(data,item_ext,root_,maxdepth_);
|
|
}
|
|
|
|
int count() const
|
|
{
|
|
return count_nodes(root_);
|
|
}
|
|
|
|
int count_items() const
|
|
{
|
|
int count=0;
|
|
count_items(root_,count);
|
|
return count;
|
|
}
|
|
|
|
void print() const
|
|
{
|
|
print(root_);
|
|
}
|
|
|
|
void trim()
|
|
{
|
|
trim_tree(root_);
|
|
}
|
|
|
|
void write(std::ostream& out)
|
|
{
|
|
char header[16];
|
|
memset(header,0,16);
|
|
header[0]='m';
|
|
header[1]='a';
|
|
header[2]='p';
|
|
header[3]='n';
|
|
header[4]='i';
|
|
header[5]='k';
|
|
out.write(header,16);
|
|
write_node(out,root_);
|
|
}
|
|
|
|
private:
|
|
|
|
void trim_tree(quadtree_node<T>*& node)
|
|
{
|
|
if (node)
|
|
{
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
trim_tree(node->children_[i]);
|
|
}
|
|
|
|
if (node->num_subnodes()==1 && node->data_.size()==0)
|
|
{
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
if (node->children_[i])
|
|
{
|
|
node=node->children_[i];
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
int count_nodes(const quadtree_node<T>* node) const
|
|
{
|
|
if (!node)
|
|
{
|
|
return 0;
|
|
}
|
|
else
|
|
{
|
|
int count = 1;
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
count += count_nodes(node->children_[i]);
|
|
}
|
|
return count;
|
|
}
|
|
}
|
|
|
|
void count_items(const quadtree_node<T>* node,int& count) const
|
|
{
|
|
if (node)
|
|
{
|
|
count += node->data_.size();
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
count_items(node->children_[i],count);
|
|
}
|
|
}
|
|
}
|
|
|
|
int subnode_offset(const quadtree_node<T>* node) const
|
|
{
|
|
int offset=0;
|
|
for (int i=0;i<4;i++)
|
|
{
|
|
if (node->children_[i])
|
|
{
|
|
offset +=sizeof(box2d<double>)+(node->children_[i]->data_.size()*sizeof(T))+3*sizeof(int);
|
|
offset +=subnode_offset(node->children_[i]);
|
|
}
|
|
}
|
|
return offset;
|
|
}
|
|
|
|
void write_node(std::ostream& out,const quadtree_node<T>* node) const
|
|
{
|
|
if (node)
|
|
{
|
|
int offset=subnode_offset(node);
|
|
int shape_count=node->data_.size();
|
|
int recsize=sizeof(box2d<double>) + 3 * sizeof(int) + shape_count * sizeof(T);
|
|
char* node_record=new char[recsize];
|
|
memset(node_record,0,recsize);
|
|
memcpy(node_record,&offset,4);
|
|
memcpy(node_record+4,&node->ext_,sizeof(box2d<double>));
|
|
memcpy(node_record+36,&shape_count,4);
|
|
for (int i=0;i<shape_count;++i)
|
|
{
|
|
memcpy(node_record + 40 + i * sizeof(T),&(node->data_[i]),sizeof(T));
|
|
}
|
|
int num_subnodes=0;
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
if (node->children_[i])
|
|
{
|
|
++num_subnodes;
|
|
}
|
|
}
|
|
memcpy(node_record + 40 + shape_count * sizeof(T),&num_subnodes,4);
|
|
out.write(node_record,recsize);
|
|
delete [] node_record;
|
|
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
write_node(out,node->children_[i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
void print(const quadtree_node<T>* node,int level=0) const
|
|
{
|
|
if (node)
|
|
{
|
|
typename std::vector<T>::const_iterator itr=node->data_.begin();
|
|
std::string pad;
|
|
for (int i=0;i<level;++i)
|
|
{
|
|
pad+=" ";
|
|
}
|
|
std::clog<<pad<<"node "<<node<<" extent:"<<node->ext_<<std::endl;
|
|
std::clog<<pad;
|
|
while(itr!=node->data_.end())
|
|
{
|
|
std::clog<<*itr<<" ";
|
|
++itr;
|
|
}
|
|
std::clog<<std::endl;
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
print(node->children_[i],level+4);
|
|
}
|
|
}
|
|
}
|
|
|
|
void insert(const T& data,const box2d<double>& item_ext,quadtree_node<T>* node,int maxdepth)
|
|
{
|
|
if (node && node->ext_.contains(item_ext))
|
|
{
|
|
coord2d c=node->ext_.center();
|
|
|
|
double width=node->ext_.width();
|
|
double height=node->ext_.height();
|
|
|
|
double lox=node->ext_.minx();
|
|
double loy=node->ext_.miny();
|
|
double hix=node->ext_.maxx();
|
|
double hiy=node->ext_.maxy();
|
|
|
|
box2d<double> ext[4];
|
|
ext[0]=box2d<double>(lox,loy,lox + width * ratio_,loy + height * ratio_);
|
|
ext[1]=box2d<double>(hix - width * ratio_,loy,hix,loy + height * ratio_);
|
|
ext[2]=box2d<double>(lox,hiy - height*ratio_,lox + width * ratio_,hiy);
|
|
ext[3]=box2d<double>(hix - width * ratio_,hiy - height*ratio_,hix,hiy);
|
|
|
|
if (maxdepth > 1)
|
|
{
|
|
for (int i=0;i<4;++i)
|
|
{
|
|
if (ext[i].contains(item_ext))
|
|
{
|
|
if (!node->children_[i])
|
|
{
|
|
node->children_[i]=new quadtree_node<T>(ext[i]);
|
|
}
|
|
insert(data,item_ext,node->children_[i],maxdepth-1);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
node->data_.push_back(data);
|
|
}
|
|
}
|
|
};
|
|
#endif //QUADTREE_HPP
|