mapnik/include/mapnik/svg_renderer.hpp

/*****************************************************************************
 * 
 * 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
 *
 *****************************************************************************/

//$Id$

#ifndef SVG_RENDERER_HPP
#define SVG_RENDERER_HPP

// mapnik
#include <mapnik/feature_style_processor.hpp>
#include <mapnik/map.hpp>

#include <mapnik/svg/svg_generator.hpp>
#include <mapnik/svg/svg_output_attributes.hpp>

// stl
#include <string>

namespace mapnik 
{
    // parameterized with the type of output iterator it will use for output.
    // output iterators add more flexibility than streams, because iterators
    // can target many other output destinations besides streams.
    template <typename OutputIterator>
    class MAPNIK_DECL svg_renderer : public feature_style_processor<svg_renderer<OutputIterator> >, 
             private boost::noncopyable
    {
    public:
        svg_renderer(Map const& m, OutputIterator& output_iterator, unsigned offset_x=0, unsigned offset_y=0);
        ~svg_renderer();
      
        void start_map_processing(Map const& map);
        void end_map_processing(Map const& map);
        void start_layer_processing(layer const& lay);
        void end_layer_processing(layer const& lay);
      
        /*!
         * @brief Overloads that process each kind of symbolizer individually.
         */
        void process(point_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(line_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(line_pattern_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(polygon_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(polygon_pattern_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(raster_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(shield_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(text_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(building_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(markers_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
        void process(glyph_symbolizer const& sym,
               Feature const& feature,
               proj_transform const& prj_trans);
      
        /*!
         * @brief Overload that process the whole set of symbolizers of a rule.
         * @return true, meaning that this renderer can process multiple symbolizers.
         */
        bool process(rule::symbolizers const& syms,
               Feature const& feature,
               proj_transform const& prj_trans);
        
        void painted(bool painted)
        {
            // nothing to do
        }

        inline OutputIterator& get_output_iterator() 
        {
            return output_iterator_;
        }
      
        inline const OutputIterator& get_output_iterator() const
        {
            return output_iterator_;
        }

    private:
        OutputIterator& output_iterator_;
        const int width_;
        const int height_;
        CoordTransform t_;
        svg::svg_generator<OutputIterator> generator_;
        svg::path_output_attributes path_attributes_;
        bool painted_;
      
        /*!
         * @brief Visitor that makes the calls to process each symbolizer when stored in a boost::variant.
         * This object follows the model of that found in feature_style_processor. It appears here, because
         * the logic that iterates over the set of symbolizer has been moved to an SVG renderer's internal
         * method.
         */
        struct symbol_dispatch : public boost::static_visitor<>
        {
            symbol_dispatch(svg_renderer<OutputIterator>& processor,
                Feature const& feature, 
                proj_transform const& prj_trans)
            : processor_(processor),
              feature_(feature),
              prj_trans_(prj_trans) {}
      
            template <typename Symbolizer>
            void operator()(Symbolizer const& sym) const
            {
                processor_.process(sym, feature_, prj_trans_);
            }
      
            svg_renderer<OutputIterator>& processor_;
            Feature const& feature_;
            proj_transform const& prj_trans_;
        };
    };
}

#endif //SVG_RENDERER_HPP