diff --git a/src/load_map.cpp b/src/load_map.cpp index 8ae3c3f14..2cd8a8601 100644 --- a/src/load_map.cpp +++ b/src/load_map.cpp @@ -149,6 +149,58 @@ private: std::string xml_base_path_; }; +void map_allow_overlap_optimization(Map &map) +{ + // Due manual rule optimization for marker symbolizers. If all styles + // use only marker symbolizers and all rules of the styles have explictly + // define allow_overlap=true, then set ignore_placement=true. This has + // both performance benefits and allows the rendering to run in constant space + // as the collision quadtree is not used. + // Note that the code can be generalized to include texts and points. + bool ignore_placement = true; + for (auto style_it = map.begin_styles(); style_it != map.end_styles(); style_it++) + { + for (auto & rule : style_it->second.get_rules_nonconst()) + { + for (auto & sym : rule) + { + if (sym.is()) + { + markers_symbolizer & marker = sym.get(); + auto prop_it = marker.properties.find(keys::allow_overlap); + if (prop_it != marker.properties.end()) + { + if (prop_it->second == true) + { + continue; + } + } + } + // In all other cases (non-marker symbolizer, allow_overlap not explictly true) do not set ignore_placement + ignore_placement = false; + break; + } + } + } + if (ignore_placement) + { + for (auto style_it = map.begin_styles(); style_it != map.end_styles(); style_it++) + { + for (auto & rule : style_it->second.get_rules_nonconst()) + { + for (auto & sym : rule) + { + if (sym.is()) + { + markers_symbolizer & marker = sym.get(); + marker.properties[keys::ignore_placement] = true; + } + } + } + } + MAPNIK_LOG_DEBUG(load_map) << "setting ignore_placement=true due to all rules having allow_overlap=true"; + } +} void load_map(Map & map, std::string const& filename, bool strict, std::string base_path) { @@ -157,6 +209,7 @@ void load_map(Map & map, std::string const& filename, bool strict, std::string b read_xml(filename, tree.root()); map_parser parser(map, strict, filename); parser.parse_map(map, tree.root(), base_path); + map_allow_overlap_optimization(map); } void load_map_string(Map & map, std::string const& str, bool strict, std::string base_path) @@ -172,6 +225,7 @@ void load_map_string(Map & map, std::string const& str, bool strict, std::string } map_parser parser(map, strict, base_path); parser.parse_map(map, tree.root(), base_path); + map_allow_overlap_optimization(map); } void map_parser::parse_map(Map & map, xml_node const& node, std::string const& base_path)