mapnik/plugins/input/raster/raster_datasource.cpp

/*****************************************************************************
 * 
 * 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::image_reader;

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")
{
 
#ifdef MAPNIK_DEBUG
   std::cout << "\nRaster Plugin: Initializing...\n";
#endif

   boost::optional<std::string> file=params.get<std::string>("file");
   if (!file) throw datasource_exception("missing <file> parameter ");
   
   boost::optional<std::string> base=params.get<std::string>("base");
   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<image_reader> reader(mapnik::get_image_reader(filename_, format_));
      if (reader.get())
      {
         width_ = reader->width();
         height_ = reader->height();
#ifdef MAPNIK_DEBUG
         std::cout << "Raster Plugin: RASTER SIZE(" << width_ << "," << height_ << ")\n";
#endif
      }
   }
   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::box2d<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::box2d<double> intersect=extent_.intersect(q.get_bbox());
   mapnik::box2d<double> ext=t.forward(intersect);
   
   int width  = int(ext.maxx() + 0.5) - int(ext.minx() + 0.5);
   int height = int(ext.maxy() + 0.5) - int(ext.miny() + 0.5);
#ifdef MAPNIK_DEBUG
   std::cout << "Raster Plugin: BOX SIZE(" << width << " " << height << ")\n";
#endif
   if (width * height > 512*512)
   {
#ifdef MAPNIK_DEBUG
      std::cout << "Raster Plugin: TILED policy\n";
#endif
      tiled_file_policy policy(filename_,format_, 256 , extent_,q.get_bbox(), width_,height_);
      return featureset_ptr(new raster_featureset<tiled_file_policy>(policy,extent_,q));
   }
   else
   {
#ifdef MAPNIK_DEBUG
      std::cout << "Raster Plugin: SINGLE FILE\n";
#endif
      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();
}