SVG - add experimental "target" width and height which overwrite SVG's outermost "width" and "height" attributes [WIP]

include/mapnik/marker_cache.hpp

@@ -56,6 +56,7 @@ public:
     bool is_svg_uri(std::string const& path);
     bool is_image_uri(std::string const& path);
     std::shared_ptr<marker const> find(std::string const& key, bool update_cache = false, bool strict = false);
+    std::shared_ptr<marker const> find(std::string const& key, double width, double height, bool update_cache = false, bool strict = false);
     void clear();
 };
 

include/mapnik/svg/svg_parser.hpp

@@ -86,12 +86,14 @@ class MAPNIK_DECL svg_parser : private util::noncopyable
 {
     using error_handler = svg_parser_error_handler;
 public:
-    explicit svg_parser(svg_converter_type & path, bool strict = false);
+    explicit svg_parser(svg_converter_type & path, double width, double height, bool strict = false);
     ~svg_parser();
     error_handler & err_handler();
     void parse(std::string const& filename);
     void parse_from_string(std::string const& svg);
     svg_converter_type & path_;
+    double width_;
+    double height_;
     bool is_defs_;
     bool strict_;
     bool ignore_;

src/marker_cache.cpp

@@ -144,6 +144,12 @@ struct visitor_create_marker
 
 std::shared_ptr<mapnik::marker const> marker_cache::find(std::string const& uri,
                                                          bool update_cache, bool strict)
+{
+    return find(uri, 0, 0, update_cache, strict);
+}
+
+std::shared_ptr<mapnik::marker const> marker_cache::find(std::string const& uri, double width, double height,
+                                                         bool update_cache, bool strict)
 {
     if (uri.empty())
     {
@@ -176,7 +182,7 @@ std::shared_ptr<mapnik::marker const> marker_cache::find(std::string const& uri,
             vertex_stl_adapter<svg_path_storage> stl_storage(marker_path->source());
             svg_path_adapter svg_path(stl_storage);
             svg_converter_type svg(svg_path, marker_path->attributes());
-            svg_parser p(svg, strict);
+            svg_parser p(svg, width, height, strict);
             p.parse_from_string(known_svg_string);
 
             if (!strict)
@@ -216,7 +222,7 @@ std::shared_ptr<mapnik::marker const> marker_cache::find(std::string const& uri,
                 vertex_stl_adapter<svg_path_storage> stl_storage(marker_path->source());
                 svg_path_adapter svg_path(stl_storage);
                 svg_converter_type svg(svg_path, marker_path->attributes());
-                svg_parser p(svg, strict);
+                svg_parser p(svg, width, height, strict);
                 p.parse(uri);
 
                 if (!strict)

src/svg/svg_parser.cpp

@@ -878,16 +878,28 @@ void parse_dimensions(svg_parser & parser, rapidxml::xml_node<char> const* node)
     viewbox vbox = {0, 0, 0, 0};
     bool has_percent_height = true;
     bool has_percent_width = true;
-
+    bool overwrite_dimensions = false;
     auto const* width_attr = node->first_attribute("width");
-    if (width_attr)
-    {
-        width = parse_svg_value(parser, width_attr->value(), has_percent_width);
-    }
     auto const* height_attr = node->first_attribute("height");
-    if (height_attr)
+
+    if (parser.width_ > 0 && parser.height_ > 0) // overwrite SVG document dimensions
     {
-        height = parse_svg_value(parser, height_attr->value(), has_percent_height);
+        has_percent_height = false;
+        has_percent_width = false;
+        overwrite_dimensions = true;
+        width = parser.width_;
+        height = parser.height_;
+    }
+    else
+    {
+        if (width_attr)
+        {
+            width = parse_svg_value(parser, width_attr->value(), has_percent_width);
+        }
+        if (height_attr)
+        {
+            height = parse_svg_value(parser, height_attr->value(), has_percent_height);
+        }
     }
     parser.vbox_ = viewbox{0, 0, width, height} ;
     auto const* viewbox_attr = node->first_attribute("viewBox");
@@ -896,12 +908,13 @@ void parse_dimensions(svg_parser & parser, rapidxml::xml_node<char> const* node)
         agg::trans_affine t{};
         parser.vbox_ = vbox;
         parser.normalized_diagonal_ = std::sqrt(vbox.width * vbox.width + vbox.height * vbox.height)/std::sqrt(2.0);
-
+        if (!overwrite_dimensions)
-        if (has_percent_width) width = vbox.width * width;
+        {
-        else if (!width_attr || width == 0) width = vbox.width;
+            if (has_percent_width) width = vbox.width * width;
-        if (has_percent_height) height = vbox.height * height;
+            else if (!width_attr || width == 0) width = vbox.width;
-        else if (!height_attr || height == 0) height = vbox.height;
+            if (has_percent_height) height = vbox.height * height;
-
+            else if (!height_attr || height == 0) height = vbox.height;
+        }
         if (width > 0 && height > 0 && vbox.width > 0 && vbox.height > 0)
         {
             std::pair<unsigned,bool> preserve_aspect_ratio {xMidYMid, true};
@@ -1583,8 +1596,10 @@ void parse_linear_gradient(svg_parser & parser, rapidxml::xml_node<char> const*
 }
 
 
-svg_parser::svg_parser(svg_converter_type & path, bool strict)
+svg_parser::svg_parser(svg_converter_type & path, double width, double height, bool strict)
     : path_(path),
+      width_(width),
+      height_(height),
       is_defs_(false),
       ignore_(false),
       css_style_(false),

test/unit/svg/svg_parser_test.cpp

@@ -48,7 +48,7 @@ namespace // internal
             : stl_storage(path.source())
             , svg_path(stl_storage)
             , svg(svg_path, path.attributes())
-            , p(svg, strict)
+            , p(svg, 0, 0, strict)
         {}
 
         mapnik::svg::svg_parser* operator->()

utils/svg2png/svg2png.cpp

@@ -152,7 +152,7 @@ struct main_marker_visitor
 
   private:
     std::string svg_name_;
-    double scale_factor_ = 1.0;
+    double scale_factor_;
     bool verbose_;
     bool auto_open_;
 };
@@ -167,6 +167,8 @@ int main (int argc,char** argv)
     int status = 0;
     std::vector<std::string> svg_files;
     mapnik::logger::instance().set_severity(mapnik::logger::error);
+    double target_width = 0.0;
+    double target_height = 0.0;
     double scale_factor = 1.0;
     std::string usage = "Usage: svg2png [options] <svg-file(s)>";
     try
@@ -179,6 +181,8 @@ int main (int argc,char** argv)
             ("open,o","automatically open the file after rendering (os x only)")
             ("strict,s","enables strict SVG parsing")
             ("scale-factor", po::value<double>(), "provide scaling factor (default: 1.0)")
+            ("width", po::value<double>(), "width of the SVG document")
+            ("height", po::value<double>(), "height of the SVG document")
             ("svg",po::value<std::vector<std::string> >(),"svg file to read")
             ;
 
@@ -219,6 +223,14 @@ int main (int argc,char** argv)
         {
             scale_factor = vm["scale-factor"].as<double>();
         }
+        if (vm.count("width"))
+        {
+            target_width = vm["width"].as<double>();
+        }
+        if (vm.count("height"))
+        {
+            target_height = vm["height"].as<double>();
+        }
         if (vm.count("svg"))
         {
             svg_files=vm["svg"].as< std::vector<std::string> >();
@@ -242,7 +254,8 @@ int main (int argc,char** argv)
             {
                 std::clog << "found: " << svg_name << "\n";
             }
-            std::shared_ptr<mapnik::marker const> marker = mapnik::marker_cache::instance().find(svg_name, false, strict);
+            std::shared_ptr<mapnik::marker const> marker =
+                mapnik::marker_cache::instance().find(svg_name, target_width, target_height, false, strict);
             main_marker_visitor visitor(svg_name, scale_factor, verbose, auto_open);
             status = mapnik::util::apply_visitor(visitor, *marker);
         }