refactor GeoJSON bounding box extraction into separate method for re-use and more...

include/mapnik/json/extract_bounding_boxes_x3.hpp

@@ -0,0 +1,35 @@
+/*****************************************************************************
+ *
+ * This file is part of Mapnik (c++ mapping toolkit)
+ *
+ * Copyright (C) 2016 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_JSON_EXTRACT_BOUNDING_BOXES_X3_HPP
+#define MAPNIK_JSON_EXTRACT_BOUNDING_BOXES_X3_HPP
+
+namespace mapnik { namespace json {
+
+template <typename Iterator, typename Boxes>
+void extract_bounding_boxes(Iterator start, Iterator end, Boxes & boxes);
+
+}}
+
+
+#endif // MAPNIK_JSON_EXTRACT_BOUNDING_BOXES_X3_HPP

include/mapnik/json/json_grammar_config.hpp

@@ -23,6 +23,8 @@
 #ifndef MAPNIK_JSON_GRAMMAR_CONFIG_HPP
 #define MAPNIK_JSON_GRAMMAR_CONFIG_HPP
 
+#include <mapnik/feature.hpp>
+#include <mapnik/unicode.hpp>
 #pragma GCC diagnostic push
 #include <mapnik/warning_ignore.hpp>
 #include <boost/spirit/home/x3.hpp>
@@ -59,6 +61,8 @@ constexpr char const* wkn_to_string(well_known_names val)
 }
 
 struct keys_tag;
+struct transcoder_tag;
+struct feature_tag;
 
 using keys_map = boost::bimap<boost::bimaps::unordered_set_of<std::string>,
                               boost::bimaps::set_of<int>>;
@@ -84,6 +88,15 @@ using iterator_type = char const*;
 using context_type = x3::with_context<keys_tag,
                                       std::reference_wrapper<keys_map> const,
                                       x3::phrase_parse_context<space_type>::type>::type;
+
+using geometry_context_type = x3::with_context<feature_tag,
+                                               std::reference_wrapper<mapnik::feature_impl> const,
+                                               context_type>::type;
+
+using feature_context_type = x3::with_context<transcoder_tag,
+                                              std::reference_wrapper<mapnik::transcoder> const,
+                                              geometry_context_type>::type;
+
 }}}
 
 #endif // MAPNIK_JSON_GRAMMAR_CONFIG_HPP

src/json/extract_bounding_boxes_x3.cpp

@@ -0,0 +1,231 @@
+/*****************************************************************************
+ *
+ * This file is part of Mapnik (c++ mapping toolkit)
+ *
+ * Copyright (C) 2016 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
+ *
+ *****************************************************************************/
+
+#include <mapnik/box2d.hpp>
+#include <mapnik/json/extract_bounding_boxes_x3.hpp>
+#include <mapnik/json/json_grammar_config.hpp>
+#include <mapnik/json/geojson_grammar_x3_def.hpp>
+#include <mapnik/json/unicode_string_grammar_x3_def.hpp>
+#include <mapnik/json/positions_grammar_x3_def.hpp>
+
+namespace mapnik { namespace json {
+
+template <typename Box>
+struct calculate_bounding_box
+{
+    calculate_bounding_box(Box & box)
+        : box_(box) {}
+
+    void operator()(mapnik::json::point const& pt) const
+    {
+        box_.init(pt.x, pt.y);
+    }
+
+    void operator()(mapnik::json::ring const& ring) const
+    {
+        for (auto const& pt : ring)
+        {
+            if (!box_.valid()) box_.init(pt.x, pt.y);
+            else box_.expand_to_include(pt.x, pt.y);
+        }
+    }
+
+    void operator()(mapnik::json::rings const& rings) const
+    {
+        for (auto const& ring : rings)
+        {
+            operator()(ring);
+            break; // consider first ring only
+        }
+    }
+
+    void operator()(mapnik::json::rings_array const& rings_array) const
+    {
+        for (auto const& rings : rings_array)
+        {
+            operator()(rings);
+        }
+    }
+
+    template <typename T>
+    void operator() (T const& ) const {}
+
+    Box & box_;
+};
+
+namespace grammar {
+
+namespace x3 = boost::spirit::x3;
+
+using base_iterator_type = char const*;
+using x3::lit;
+using x3::omit;
+using x3::raw;
+using x3::char_;
+using x3::eps;
+
+struct feature_callback_tag;
+
+auto on_feature_callback = [] (auto const& ctx)
+{
+    // call our callback
+    x3::get<feature_callback_tag>(ctx)(_attr(ctx));
+};
+
+namespace {
+auto const& geojson_value = geojson_grammar();
+}
+
+// extract bounding box from GeoJSON Feature
+
+struct bracket_tag ;
+
+auto check_brackets = [](auto const& ctx)
+{
+    _pass(ctx) = (x3::get<bracket_tag>(ctx) > 0);
+};
+
+auto open_bracket = [](auto const& ctx)
+{
+    ++x3::get<bracket_tag>(ctx);
+};
+
+auto close_bracket = [](auto const& ctx)
+{
+    --x3::get<bracket_tag>(ctx);
+};
+
+auto assign_range = [](auto const& ctx)
+{
+    std::get<0>(_val(ctx)) = std::move(_attr(ctx));
+};
+
+auto assign_bbox = [](auto const& ctx)
+{
+    std::get<1>(_val(ctx)) = std::move(_attr(ctx));
+};
+
+auto extract_bounding_box = [](auto const& ctx)
+{
+    mapnik::box2d<double> bbox;
+    calculate_bounding_box<mapnik::box2d<double>> visitor(bbox);
+    mapnik::util::apply_visitor(visitor, _attr(ctx));
+    _val(ctx) = std::move(bbox);
+};
+
+auto const coordinates_rule = x3::rule<struct coordinates_rule_tag, mapnik::box2d<double> > {}
+    = lit("\"coordinates\"") >> lit(':') >> positions_rule[extract_bounding_box];
+
+auto const bounding_box = x3::rule<struct bounding_box_rule_tag, std::tuple<boost::iterator_range<base_iterator_type>,mapnik::box2d<double>>> {}
+    = raw[lit('{')[open_bracket] >> *(eps[check_brackets] >>
+                                  (lit("\"FeatureCollection\"") > eps(false)
+                                   |
+                                   lit('{')[open_bracket]
+                                   |
+                                   lit('}')[close_bracket]
+                                   |
+                                   coordinates_rule[assign_bbox]
+                                   |
+                                   omit[geojson_string]
+                                   |
+                                   omit[char_]))][assign_range];
+
+
+auto const feature = bounding_box[on_feature_callback];
+
+auto const key_value_ = omit[geojson_string] > lit(':') > omit[geojson_value] ;
+
+auto const features = lit("\"features\"")
+    > lit(':') > lit('[') > -(omit[feature] % lit(',')) > lit(']');
+
+auto const type = lit("\"type\"") > lit(':') > lit("\"FeatureCollection\"");
+
+auto const feature_collection = x3::rule<struct feature_collection_tag> {}
+    = lit('{') > (( type | features | key_value_) % lit(',')) > lit('}');
+
+
+}
+
+namespace {
+struct collect_features
+{
+    collect_features(std::vector<mapnik::json::geojson_value> & values)
+        : values_(values) {}
+    void operator() (mapnik::json::geojson_value && val) const
+    {
+        values_.push_back(std::move(val));
+    }
+    std::vector<mapnik::json::geojson_value> & values_;
+};
+
+template <typename Iterator, typename Boxes>
+struct extract_positions
+{
+    extract_positions(Iterator start, Boxes & boxes)
+        : start_(start),
+          boxes_(boxes) {}
+
+    template <typename T>
+    void operator() (T const& val) const
+    {
+        auto const& r = std::get<0>(val);
+        mapnik::box2d<double> const& bbox = std::get<1>(val);
+        auto offset = std::distance(start_, r.begin());
+        auto size = std::distance(r.begin(), r.end());
+        boxes_.emplace_back(std::make_pair(bbox,std::make_pair(offset, size)));
+        //boxes_.emplace_back(std::make_tuple(bbox,offset, size));
+    }
+    Iterator start_;
+    Boxes & boxes_;
+};
+
+}
+
+template <typename Iterator, typename Boxes>
+void extract_bounding_boxes(Iterator start, Iterator end, Boxes & boxes)
+{
+    using namespace boost::spirit;
+    using space_type = mapnik::json::grammar::space_type;
+    using iterator_type = Iterator;
+    using boxes_type = Boxes;
+
+    extract_positions<iterator_type, boxes_type> callback(start, boxes);
+    auto keys = mapnik::json::get_keys();
+    std::size_t bracket_counter = 0;
+    auto feature_collection_impl = x3::with<mapnik::json::grammar::bracket_tag>(std::ref(bracket_counter))
+        [x3::with<mapnik::json::keys_tag>(std::ref(keys))
+         [x3::with<mapnik::json::grammar::feature_callback_tag>(std::ref(callback))
+          [mapnik::json::grammar::feature_collection]
+             ]];
+
+    if (!x3::phrase_parse(start, end, feature_collection_impl, space_type()))
+    {
+        throw std::runtime_error("Can't extract bounding boxes");
+    }
+
+}
+
+using box_type = mapnik::box2d<double>;
+using boxes_type = std::vector<std::pair<box_type, std::pair<std::size_t, std::size_t>>>;
+using base_iterator_type = char const*;
+template void extract_bounding_boxes<base_iterator_type, boxes_type>(base_iterator_type, base_iterator_type, boxes_type&);
+}}

src/json/geojson_grammar_x3.cpp

@@ -20,10 +20,12 @@
  *
  *****************************************************************************/
 
+#if 0
 #include <mapnik/json/geojson_grammar_x3_def.hpp>
 #include <mapnik/json/json_grammar_config.hpp>
+
 namespace mapnik { namespace json { namespace grammar {
-
 BOOST_SPIRIT_INSTANTIATE(geojson_grammar_type, iterator_type, context_type);
-
 }}}
+
+#endif

src/json/parse_feature.cpp

@@ -21,10 +21,10 @@
  *****************************************************************************/
 
 #include <mapnik/json/parse_feature.hpp>
+#include <mapnik/json/json_grammar_config.hpp>
 #include <mapnik/json/generic_json_grammar_x3_def.hpp>
 #include <mapnik/json/unicode_string_grammar_x3_def.hpp>
 #include <mapnik/json/positions_grammar_x3_def.hpp>
-#include <mapnik/json/json_grammar_config.hpp>
 #include <mapnik/json/create_geometry.hpp>
 #include <mapnik/util/conversions.hpp>
 
@@ -133,9 +133,6 @@ using x3::lit;
 using x3::omit;
 using x3::char_;
 
-struct transcoder_tag;
-struct feature_tag;
-//
 auto const& value = mapnik::json::generic_json_grammar();
 // import unicode string rule
 auto const& geojson_string = unicode_string_grammar();
@@ -230,7 +227,7 @@ auto const feature_part = x3::rule<struct feature_part_rule_tag> {} =
     omit[geojson_string] > lit(':') > omit[value]
     ;
 
-auto const feature = x3::rule<struct feature_rule_tag> {} =
+auto const feature_rule = x3::rule<struct feature_rule_tag> {} =
     lit('{') > feature_part % lit(',') > lit('}')
     ;
 
@@ -244,7 +241,7 @@ void parse_feature(Iterator start, Iterator end, feature_impl& feature, mapnik::
     using space_type = mapnik::json::grammar::space_type;
     auto grammar = x3::with<mapnik::json::transcoder_tag>(std::ref(tr))
         [x3::with<mapnik::json::feature_tag>(std::ref(feature))
-         [ mapnik::json::feature ]];
+         [ mapnik::json::feature_rule ]];
     if (!x3::phrase_parse(start, end, grammar, space_type()))
     {
         throw std::runtime_error("Can't parser GeoJSON Feature");

src/json/positions_grammar_x3.cpp

@@ -20,9 +20,11 @@
  *
  *****************************************************************************/
 
+#if 0
 #include <mapnik/json/positions_grammar_x3_def.hpp>
 #include <mapnik/json/json_grammar_config.hpp>
 
 namespace mapnik { namespace json { namespace grammar {
 BOOST_SPIRIT_INSTANTIATE(positions_grammar_type, iterator_type, context_type);
 }}}
+#endif

src/json/unicode_string_grammar_x3.cpp

@@ -19,10 +19,12 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  *
  *****************************************************************************/
-
+#if 0
 #include <mapnik/json/unicode_string_grammar_x3_def.hpp>
 #include <mapnik/json/json_grammar_config.hpp>
 
 namespace mapnik { namespace json { namespace grammar {
 BOOST_SPIRIT_INSTANTIATE(unicode_string_grammar_type, iterator_type, context_type);
 }}}
+
+#endif

utils/mapnik-index/process_geojson_file_x3.cpp

@@ -35,9 +35,11 @@
 #endif
 #include <mapnik/feature.hpp>
 #include <mapnik/json/json_grammar_config.hpp>
-#include <mapnik/json/geojson_grammar_x3_def.hpp>
+#include <mapnik/json/geojson_grammar_x3.hpp>
-#include <mapnik/json/unicode_string_grammar_x3_def.hpp>
+#include <mapnik/json/unicode_string_grammar_x3.hpp>
-#include <mapnik/json/positions_grammar_x3_def.hpp>
+#include <mapnik/json/positions_grammar_x3.hpp>
+
+#include <mapnik/json/extract_bounding_boxes_x3.hpp>
 
 namespace {
 
@@ -211,185 +213,17 @@ bool validate_geojson_feature(mapnik::json::geojson_value & value, Keys const& k
     return true;
 };
 
-using box_type = mapnik::box2d<float>;
+using box_type = mapnik::box2d<double>;
 using boxes_type = std::vector<std::pair<box_type, std::pair<std::size_t, std::size_t>>>;
 using base_iterator_type = char const*;
-}
 
-namespace mapnik { namespace json {
+auto const& geojson_value = mapnik::json::geojson_grammar();
-
-template <typename Box>
-struct calculate_bounding_box
-{
-    calculate_bounding_box(Box & box)
-        : box_(box) {}
-
-    void operator()(mapnik::json::point const& pt) const
-    {
-        box_.init(pt.x, pt.y);
-    }
-
-    void operator()(mapnik::json::ring const& ring) const
-    {
-        for (auto const& pt : ring)
-        {
-            if (!box_.valid()) box_.init(pt.x, pt.y);
-            else box_.expand_to_include(pt.x, pt.y);
-        }
-    }
-
-    void operator()(mapnik::json::rings const& rings) const
-    {
-        for (auto const& ring : rings)
-        {
-            operator()(ring);
-            break; // consider first ring only
-        }
-    }
-
-    void operator()(mapnik::json::rings_array const& rings_array) const
-    {
-        for (auto const& rings : rings_array)
-        {
-            operator()(rings);
-        }
-    }
-
-    template <typename T>
-    void operator() (T const& ) const {}
-
-    Box & box_;
-};
-
-namespace grammar {
-
-namespace x3 = boost::spirit::x3;
-
-using x3::lit;
-using x3::omit;
-using x3::raw;
-using x3::char_;
-using x3::eps;
-
-struct feature_callback_tag;
-
-auto on_feature_callback = [] (auto const& ctx)
-{
-    // call our callback
-    x3::get<feature_callback_tag>(ctx)(_attr(ctx));
-};
-
-namespace {
-auto const& geojson_value = geojson_grammar();
-}
-
-// extract bounding box from GeoJSON Feature
-
-struct bracket_tag ;
-
-auto check_brackets = [](auto const& ctx)
-{
-    _pass(ctx) = (x3::get<bracket_tag>(ctx) > 0);
-};
-
-auto open_bracket = [](auto const& ctx)
-{
-    ++x3::get<bracket_tag>(ctx);
-};
-
-auto close_bracket = [](auto const& ctx)
-{
-    --x3::get<bracket_tag>(ctx);
-};
-
-auto assign_range = [](auto const& ctx)
-{
-    std::get<0>(_val(ctx)) = std::move(_attr(ctx));
-};
-
-auto assign_bbox = [](auto const& ctx)
-{
-    std::get<1>(_val(ctx)) = std::move(_attr(ctx));
-};
-
-auto extract_bounding_box = [](auto const& ctx)
-{
-    mapnik::box2d<float>  bbox;
-    calculate_bounding_box<mapnik::box2d<float>> visitor(bbox);
-    mapnik::util::apply_visitor(visitor, _attr(ctx));
-    _val(ctx) = std::move(bbox);
-};
-
-auto const coordinates_rule = x3::rule<struct coordinates_rule_tag, mapnik::box2d<float> > {}
-    = lit("\"coordinates\"") >> lit(':') >> positions_rule[extract_bounding_box];
-
-auto const bounding_box = x3::rule<struct bounding_box_rule_tag, std::tuple<boost::iterator_range<base_iterator_type>,mapnik::box2d<float>>> {}
-    = raw[lit('{')[open_bracket] >> *(eps[check_brackets] >>
-                                  (lit("\"FeatureCollection\"") > eps(false)
-                                   |
-                                   lit('{')[open_bracket]
-                                   |
-                                   lit('}')[close_bracket]
-                                   |
-                                   coordinates_rule[assign_bbox]
-                                   |
-                                   omit[geojson_string]
-                                   |
-                                   omit[char_]))][assign_range];
-
-
-auto const feature = bounding_box[on_feature_callback];
-
-auto const key_value_ = omit[geojson_string] > lit(':') > omit[geojson_value] ;
-
-auto const features = lit("\"features\"")
-    > lit(':') > lit('[') > -(omit[feature] % lit(',')) > lit(']');
-
-auto const type = lit("\"type\"") > lit(':') > lit("\"FeatureCollection\"");
-
-auto const feature_collection = x3::rule<struct feature_collection_tag> {}
-    = lit('{') > (( type | features | key_value_) % lit(',')) > lit('}');
-
-
-}}}
-
-namespace {
-struct collect_features
-{
-    collect_features(std::vector<mapnik::json::geojson_value> & values)
-        : values_(values) {}
-    void operator() (mapnik::json::geojson_value && val) const
-    {
-        values_.push_back(std::move(val));
-    }
-    std::vector<mapnik::json::geojson_value> & values_;
-};
-
-template <typename Iterator, typename Boxes>
-struct extract_positions
-{
-    extract_positions(Iterator start, Boxes & boxes)
-        : start_(start),
-          boxes_(boxes) {}
-
-    template <typename T>
-    void operator() (T const& val) const
-    {
-        auto const& r = std::get<0>(val);
-        mapnik::box2d<float> const& bbox = std::get<1>(val);
-        auto offset = std::distance(start_, r.begin());
-        auto size = std::distance(r.begin(), r.end());
-        boxes_.emplace_back(std::make_pair(bbox,std::make_pair(offset, size)));
-        //boxes_.emplace_back(std::make_tuple(bbox,offset, size));
-    }
-    Iterator start_;
-    Boxes & boxes_;
-};
 
 }
 
 namespace mapnik { namespace detail {
 
+
 template <typename T>
 std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & boxes, std::string const& filename, bool validate_features, bool verbose)
 {
@@ -423,29 +257,12 @@ std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & b
     base_iterator_type start = file_buffer.c_str();
     base_iterator_type end = start + file_buffer.length();
 #endif
-    using namespace boost::spirit;
-    using space_type = mapnik::json::grammar::space_type;
-    auto const* itr = start;
-
-    extract_positions<base_iterator_type, boxes_type> callback(itr, boxes);
-    auto keys = mapnik::json::get_keys();
-    std::size_t bracket_counter = 0;
-    auto feature_collection_impl = x3::with<mapnik::json::grammar::bracket_tag>(std::ref(bracket_counter))
-        [x3::with<mapnik::json::keys_tag>(std::ref(keys))
-         [x3::with<mapnik::json::grammar::feature_callback_tag>(std::ref(callback))
-          [mapnik::json::grammar::feature_collection]
-             ]];
 
     try
     {
-        bool result = x3::phrase_parse(itr, end, feature_collection_impl, space_type());
+        mapnik::json::extract_bounding_boxes(start, end, boxes);
-        if (!result)
-        {
-            std::clog << "mapnik-index (GeoJSON) : could not extract bounding boxes from : '" <<  filename <<  "'" << std::endl;
-            return std::make_pair(false, extent);
-        }
     }
-    catch (x3::expectation_failure<base_iterator_type> const& ex)
+    catch (boost::spirit::x3::expectation_failure<base_iterator_type> const& ex)
     {
         std::clog << ex.what() << std::endl;
         std::clog << "Expected: " << ex.which();
@@ -454,12 +271,16 @@ std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & b
     }
     catch (std::exception const& ex)
     {
-        std::clog << "Exception caught:" << ex.what() <<  std::endl;
+        std::clog << "mapnik-index (GeoJSON) : could not extract bounding boxes from : '" <<  filename <<  "'" << std::endl;
         return std::make_pair(false, extent);
     }
 
+    using namespace boost::spirit;
+    using space_type = mapnik::json::grammar::space_type;
+
+    auto keys = mapnik::json::get_keys();
     auto feature_grammar = x3::with<mapnik::json::keys_tag>(std::ref(keys))
-        [ mapnik::json::grammar::geojson_value ];
+        [ geojson_value ];
     for (auto const& item : boxes)
     {
         if (item.first.valid())
@@ -469,6 +290,7 @@ std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & b
 
             if (validate_features)
             {
+#if 0
                 base_iterator_type feat_itr = start + item.second.first;
                 base_iterator_type feat_end = feat_itr + item.second.second;
                 mapnik::json::geojson_value feature_value;
@@ -494,6 +316,7 @@ std::pair<bool,typename T::value_type::first_type> process_geojson_file_x3(T & b
                 {
                     return std::make_pair(false, extent);
                 }
+#endif
             }
         }
     }