/***************************************************************************** * * This file is part of Mapnik (c++ mapping toolkit) * * Copyright (C) 2011 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 * *****************************************************************************/ #if defined(SVG_RENDERER) // mapnik #include namespace mapnik { struct symbol_type_dispatch : public boost::static_visitor { template bool operator()(Symbolizer const& sym) const { return false; } bool operator()(line_symbolizer const& sym) const { return true; } bool operator()(polygon_symbolizer const& sym) const { return true; } }; bool is_path_based(symbolizer const& sym) { return boost::apply_visitor(symbol_type_dispatch(), sym); } template bool svg_renderer::process(rule::symbolizers const& syms, mapnik::feature_impl & feature, proj_transform const& prj_trans) { // svg renderer supports processing of multiple symbolizers. typedef coord_transform path_type; bool process_path = false; // process each symbolizer to collect its (path) information. // path information (attributes from line_ and polygon_ symbolizers) // is collected with the path_attributes_ data member. for (auto const& sym : syms) { if (is_path_based(sym)) { process_path = true; } boost::apply_visitor(symbol_dispatch(*this, feature, prj_trans), sym); } if (process_path) { // generate path output for each geometry of the current feature. for (auto & geom : feature.paths()) { if(geom.size() > 0) { path_type path(common_.t_, geom, prj_trans); generator_.generate_path(path, path_attributes_); } } // set the previously collected values back to their defaults // for the feature that will be processed next. path_attributes_.reset(); } return true; } template bool svg_renderer >::process(rule::symbolizers const& syms, mapnik::feature_impl & feature, proj_transform const& prj_trans); } #endif