mapnik/plugins/input/raster/raster_datasource.cpp
Artem Pavlenko 47c3bc515d + add 'tiled' policy to avoid loading very large rasters into memory
if (width*height > 1024*1024) : load raster in 1024x1024 chunks
  else : use single_file_policy

  TODO: Expose chunk size as raster_datasource parameter
2009-04-10 12:05:31 +00:00

144 lines
4.3 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: raster_datasource.cc 44 2005-04-22 18:53:54Z pavlenko $
// boost
#include <boost/lexical_cast.hpp>
#include <boost/filesystem/operations.hpp>
// mapnik
#include <mapnik/image_reader.hpp>
#include "raster_featureset.hpp"
#include "raster_info.hpp"
#include "raster_datasource.hpp"
using mapnik::datasource;
using mapnik::parameters;
using mapnik::ImageReader;
DATASOURCE_PLUGIN(raster_datasource)
using std::clog;
using std::endl;
using boost::lexical_cast;
using boost::bad_lexical_cast;
using mapnik::layer_descriptor;
using mapnik::featureset_ptr;
using mapnik::query;
using mapnik::coord2d;
using mapnik::datasource_exception;
raster_datasource::raster_datasource(const parameters& params)
: datasource (params),
desc_(*params.get<std::string>("type"),"utf-8")
{
boost::optional<std::string> file=params.get<std::string>("file");
boost::optional<std::string> base=params.get<std::string>("base");
if (!file) throw datasource_exception("missing <file> parameter ");
if (base)
filename_ = *base + "/" + *file;
else
filename_ = *file;
if (!boost::filesystem::exists(filename_)) throw datasource_exception(filename_ + " does not exist");
format_=*params.get<std::string>("format","tiff");
boost::optional<double> lox = params.get<double>("lox");
boost::optional<double> loy = params.get<double>("loy");
boost::optional<double> hix = params.get<double>("hix");
boost::optional<double> hiy = params.get<double>("hiy");
if (lox && loy && hix && hiy)
{
extent_.init(*lox,*loy,*hix,*hiy);
}
else throw datasource_exception("<lox> <loy> <hix> <hiy> are required");
try
{
std::auto_ptr<ImageReader> reader(mapnik::get_image_reader(filename_, format_));
if (reader.get())
{
width_ = reader->width();
height_ = reader->height();
std::cout << "RASTER SIZE("<<width_ << "," << height_ << ")\n";
}
}
catch (...)
{
std::cerr << "Exception caught\n";
}
}
raster_datasource::~raster_datasource() {}
int raster_datasource::type() const
{
return datasource::Raster;
}
std::string raster_datasource::name_="raster";
std::string raster_datasource::name()
{
return name_;
}
mapnik::Envelope<double> raster_datasource::envelope() const
{
return extent_;
}
layer_descriptor raster_datasource::get_descriptor() const
{
return desc_;
}
featureset_ptr raster_datasource::features(query const& q) const
{
mapnik::CoordTransform t(width_,height_,extent_,0,0);
mapnik::Envelope<double> intersect=extent_.intersect(q.get_bbox());
mapnik::Envelope<double> ext=t.forward(intersect);
unsigned width = int(ext.width()+0.5);
unsigned height = int(ext.height() + 0.5);
std::cout << width << " " << height << "\n";
if (width * height > 1024*1024)
{
std::cout << "TILED policy\n";
tiled_file_policy policy(filename_,format_, 1024, extent_,q.get_bbox(), width_,height_);
return featureset_ptr(new raster_featureset<tiled_file_policy>(policy,extent_,q));
}
else
{
std::cout << "SINGLE FILE\n";
raster_info info(filename_,format_,extent_,width_,height_);
single_file_policy policy(info);
return featureset_ptr(new raster_featureset<single_file_policy>(policy,extent_,q));
}
}
featureset_ptr raster_datasource::features_at_point(coord2d const&) const
{
return featureset_ptr();
}