mapnik/src/memory_datasource.cpp
2010-06-02 11:03:30 +00:00

103 lines
2.8 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
*
*****************************************************************************/
//$Id$
#include <mapnik/memory_datasource.hpp>
#include <mapnik/memory_featureset.hpp>
#include <algorithm>
namespace mapnik {
struct accumulate_extent
{
accumulate_extent(box2d<double> & ext)
: ext_(ext),first_(true) {}
void operator() (feature_ptr feat)
{
for (unsigned i=0;i<feat->num_geometries();++i)
{
geometry2d & geom = feat->get_geometry(i);
if ( first_ )
{
first_ = false;
ext_ = geom.envelope();
}
else
{
ext_.expand_to_include(geom.envelope());
}
}
}
box2d<double> & ext_;
bool first_;
};
memory_datasource::memory_datasource()
: datasource(parameters()) {}
memory_datasource::~memory_datasource() {}
void memory_datasource::push(feature_ptr feature)
{
features_.push_back(feature);
}
int memory_datasource::type() const
{
return datasource::Vector;
}
featureset_ptr memory_datasource::features(const query& q) const
{
return featureset_ptr(new memory_featureset(q.get_bbox(),*this));
}
featureset_ptr memory_datasource::features_at_point(coord2d const& pt) const
{
box2d<double> box = box2d<double>(pt.x, pt.y, pt.x, pt.y);
#ifdef MAPNIK_DEBUG
std::clog << "box=" << box << ", pt x=" << pt.x << ", y=" << pt.y << "\n";
#endif
return featureset_ptr(new memory_featureset(box,*this));
}
box2d<double> memory_datasource::envelope() const
{
box2d<double> ext;
accumulate_extent func(ext);
std::for_each(features_.begin(),features_.end(),func);
return ext;
}
layer_descriptor memory_datasource::get_descriptor() const
{
return layer_descriptor("in-memory datasource","utf-8");
}
size_t memory_datasource::size() const
{
return features_.size();
}
}