feature_style_processor.hpp

/*****************************************************************************
 *
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2021 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
 *
 *****************************************************************************/

#ifndef MAPNIK_FEATURE_STYLE_PROCESSOR_HPP
#define MAPNIK_FEATURE_STYLE_PROCESSOR_HPP

// mapnik
#include <mapnik/geometry/box2d.hpp>
#include <mapnik/featureset.hpp>
#include <mapnik/config.hpp>
#include <mapnik/feature_style_processor_context.hpp>

// stl
#include <vector>
#include <set>
#include <string>

namespace mapnik {

class Map;
class layer;
class projection;
class proj_transform;
class feature_type_style;
class rule_cache;
struct layer_rendering_material;

enum eAttributeCollectionPolicy { DEFAULT = 0, COLLECT_ALL = 1 };

template<typename Processor>
class MAPNIK_DECL feature_style_processor
{
  public:
    explicit feature_style_processor(Map const& m, double scale_factor = 1.0);

    /*!
     * \brief apply renderer to all map layers.
     */
    void apply(double scale_denom_override = 0.0);

    /*!
     * \brief apply renderer to a single layer, providing pre-populated set of query attribute names.
     */
    void apply(mapnik::layer const& lyr, std::set<std::string>& names, double scale_denom_override = 0.0);

    /*!
     * \brief render a layer given a projection and scale.
     */
    void apply_to_layer(layer const& lay,
                        Processor& p,
                        projection const& proj0,
                        double scale,
                        double scale_denom,
                        unsigned width,
                        unsigned height,
                        box2d<double> const& extent,
                        int buffer_size,
                        std::set<std::string>& names);

  private:
    /*!
     * \brief renders a featureset with the given styles.
     */
    void render_style(Processor& p,
                      feature_type_style const* style,
                      rule_cache const& rules,
                      featureset_ptr features,
                      proj_transform const& prj_trans);

    void prepare_layers(layer_rendering_material& parent_mat,
                        std::vector<layer> const& layers,
                        feature_style_context_map& ctx_map,
                        Processor& p,
                        double scale_denom);

    /*!
     * \brief prepare features for rendering asynchronously.
     */
    void prepare_layer(layer_rendering_material& mat,
                       feature_style_context_map& ctx_map,
                       Processor& p,
                       double scale,
                       double scale_denom,
                       unsigned width,
                       unsigned height,
                       box2d<double> const& extent,
                       int buffer_size,
                       std::set<std::string>& names);

    /*!
     * \brief render features list queued when they are available.
     */
    void render_material(layer_rendering_material const& mat, Processor& p);
    void render_submaterials(layer_rendering_material const& mat, Processor& p);

    Map const& m_;
};
} // namespace mapnik

#endif // MAPNIK_FEATURE_STYLE_PROCESSOR_HPP