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Generalize overlap_optimization to use points and text too

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This commit is contained in:
Raul Marin 2018-04-27 17:09:03 +02:00
parent 0a2be27ba9
commit 3171b89fea
1 changed files with 42 additions and 24 deletions
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66
src/load_map.cpp
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@ -149,51 +149,69 @@ private:
std::string xml_base_path_;
};
void map_allow_overlap_optimization(Map &map)
struct allow_overlap_visitor
{
bool operator()(point_symbolizer const&) { return true; }
bool operator()(line_symbolizer const&) { return false; }
bool operator()(line_pattern_symbolizer const&) { return false; }
bool operator()(polygon_symbolizer const&) { return false; }
bool operator()(polygon_pattern_symbolizer const&) { return false; }
bool operator()(raster_symbolizer const&) { return false; }
bool operator()(shield_symbolizer const&) { return false; }
bool operator()(text_symbolizer const&) { return true; }
bool operator()(building_symbolizer const&) { return false; }
bool operator()(markers_symbolizer const&) { return true; }
bool operator()(group_symbolizer const&) { return false; }
bool operator()(debug_symbolizer const&) { return true; } //Requires the quadtree
bool operator()(dot_symbolizer const&) { return false; }
};
// If all symbolizers declare 'allow_overlap: true' (their placement is independent
// from already placed symbols), there is no need to check collisions with subsequent
// symbolizers. To avoid building the quadtree unnecessarily we set
// the 'ignore_placement' flag
void map_apply_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 const & style : map.styles())
{
for (auto & rule : style_it->second.get_rules_nonconst())
for (auto const & rule : style.second.get_rules())
{
for (auto & sym : rule)
for (auto const & sym : rule)
{
if (sym.is<markers_symbolizer>())
struct allow_overlap_visitor visitor;
if (util::apply_visitor(visitor, sym))
{
markers_symbolizer & marker = sym.get<markers_symbolizer>();
auto prop_it = marker.properties.find(keys::allow_overlap);
if (prop_it != marker.properties.end())
symbolizer_base const & sb = sym.get_unchecked<markers_symbolizer>();
auto prop_it = sb.properties.find(keys::allow_overlap);
if (prop_it != sb.properties.end())
{
if (prop_it->second == true)
{
continue;
}
}
ignore_placement = false;
break;
}
// 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 & style : map.styles())
{
for (auto & rule : style_it->second.get_rules_nonconst())
for (auto & rule : style.second.get_rules_nonconst())
{
for (auto & sym : rule)
{
if (sym.is<markers_symbolizer>())
struct allow_overlap_visitor visitor;
if (util::apply_visitor(visitor, sym))
{
markers_symbolizer & marker = sym.get<markers_symbolizer>();
marker.properties[keys::ignore_placement] = true;
symbolizer_base & sb = sym.get_unchecked<markers_symbolizer>();
sb.properties[keys::ignore_placement] = true;
}
}
}
@ -209,7 +227,7 @@ 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);
map_apply_overlap_optimization(map);
}
void load_map_string(Map & map, std::string const& str, bool strict, std::string base_path)
@ -225,7 +243,7 @@ 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);
map_apply_overlap_optimization(map);
}
void map_parser::parse_map(Map & map, xml_node const& node, std::string const& base_path)