optimized WKTReader for parsing WKT into geometry paths

bindings/python/mapnik_python.cpp

@@ -75,6 +75,7 @@ void export_view_transform();
 void export_raster_colorizer();
 void export_label_collision_detector();
 void export_logger();
+void export_wkt_reader();
 
 #include <mapnik/version.hpp>
 #include <mapnik/value_error.hpp>
@@ -535,6 +536,7 @@ BOOST_PYTHON_MODULE(_mapnik)
     export_raster_colorizer();
     export_label_collision_detector();
     export_logger();
+    export_wkt_reader();
 
     def("clear_cache", &clear_cache,
         "\n"

bindings/python/mapnik_wkt_reader.cpp

@@ -0,0 +1,55 @@
+/*****************************************************************************
+ *
+ * This file is part of Mapnik (c++ mapping toolkit)
+ *
+ * Copyright (C) 2013 Artem Pavlenko, Jean-Francois Doyon
+ *
+ * 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
+ *
+ *****************************************************************************/
+
+// boost
+#include <boost/python.hpp>
+#include <boost/noncopyable.hpp>
+#include <boost/shared_ptr.hpp>
+#include <boost/ptr_container/ptr_vector.hpp>
+#include <boost/make_shared.hpp>
+// mapnik
+#include <mapnik/geometry.hpp>
+#include <mapnik/wkt/wkt_factory.hpp>
+
+namespace  impl {
+
+typedef boost::ptr_vector<mapnik::geometry_type> path_type;
+
+boost::shared_ptr<path_type> from_wkt(mapnik::wkt_parser & p, std::string const& wkt)
+{
+    boost::shared_ptr<path_type> paths = boost::make_shared<path_type>();
+    if (!p.parse(wkt, *paths))
+        throw std::runtime_error("Failed to parse WKT");
+    return paths;
+}
+
+}
+
+void export_wkt_reader()
+{
+    using mapnik::wkt_parser;
+    using namespace boost::python;
+
+    class_<wkt_parser, boost::noncopyable>("WKTReader",init<>())
+        .def("read",&impl::from_wkt)
+        ;
+}

tests/python_tests/geometry_io_test.py

@@ -102,10 +102,15 @@ def test_geojson_parsing():
             pass
     eq_(count,len(path))
 
+reader = mapnik.WKTReader()
+
 def compare_wkb_from_wkt(wkt,num=None):
 
     # create a Path from geometry(s)
-    paths = mapnik.Path.from_wkt(wkt)
+    # easy api, but slower
+    #paths = mapnik.Path.from_wkt(wkt)
+    # fast api
+    paths = reader.read(wkt);
 
     # add geometry(s) to feature from wkt
     f = mapnik.Feature(mapnik.Context(),1)
@@ -136,7 +141,10 @@ def compare_wkb_from_wkt(wkt,num=None):
 
 def compare_wkt_from_wkt(wkt,num=None):
     # create a Path from geometry(s)
-    paths = mapnik.Path.from_wkt(wkt)
+    # easy api, but slower
+    #paths = mapnik.Path.from_wkt(wkt)
+    # fast api
+    paths = reader.read(wkt);
 
     # add geometry(s) to feature from wkt
     f = mapnik.Feature(mapnik.Context(),1)
@@ -185,7 +193,10 @@ def test_wkb_simple():
 @raises(IndexError)
 def test_geometry_index_error():
     wkt = 'Point (0 0)'
-    paths = mapnik.Path.from_wkt(wkt)
+    # easy api, but slower
+    #paths = mapnik.Path.from_wkt(wkt)
+    # fast api
+    paths = reader.read(wkt);
     paths[3]
     f = mapnik.Feature(mapnik.Context(),1)
     f.add_geometries_from_wkt(wkt)