v0.2.50..v0.2.51 changeset IntersectionOverUnionExtractor.cpp

diff --git a/hoot-core/src/main/cpp/hoot/core/algorithms/extractors/IntersectionOverUnionExtractor.cpp b/hoot-core/src/main/cpp/hoot/core/algorithms/extractors/IntersectionOverUnionExtractor.cpp
new file mode 100644
index 0000000..e56b267
--- /dev/null
+++ b/hoot-core/src/main/cpp/hoot/core/algorithms/extractors/IntersectionOverUnionExtractor.cpp
@@ -0,0 +1,70 @@
+/*
+ * This file is part of Hootenanny.
+ *
+ * Hootenanny is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * --------------------------------------------------------------------
+ *
+ * The following copyright notices are generated automatically. If you
+ * have a new notice to add, please use the format:
+ * " * @copyright Copyright ..."
+ * This will properly maintain the copyright information. DigitalGlobe
+ * copyrights will be updated automatically.
+ *
+ * @copyright Copyright (C) 2019 DigitalGlobe (http://www.digitalglobe.com/)
+ */
+#include "IntersectionOverUnionExtractor.h"
+
+// Hoot
+#include <hoot/core/elements/OsmMap.h>
+#include <hoot/core/elements/ElementConverter.h>
+
+namespace hoot
+{
+
+double IntersectionOverUnionExtractor::extract(
+  const OsmMap& map, const ConstElementPtr& target, const ConstElementPtr& candidate) const
+{
+  // only calc'ing this for way polys...not sure it makes sense with anything else
+
+  if (target->getElementType() == ElementType::Way &&
+      candidate->getElementType() == ElementType::Way)
+  {
+    ElementConverter elementConverter(map.shared_from_this());
+    std::shared_ptr<geos::geom::Geometry> targetGeom = elementConverter.convertToGeometry(target);
+    std::shared_ptr<geos::geom::Geometry> candidateGeom =
+      elementConverter.convertToGeometry(candidate);
+    if (!targetGeom->isEmpty() && !candidateGeom->isEmpty())
+    {
+      std::shared_ptr<geos::geom::Geometry> intersectionGeom(
+        targetGeom->intersection(candidateGeom.get()));
+      std::shared_ptr<geos::geom::Geometry> unionGeom(
+        targetGeom->Union(candidateGeom.get()));
+
+      if (intersectionGeom && unionGeom)
+      {
+        const double intersectionArea = intersectionGeom->getArea();
+        const double unionArea = unionGeom->getArea();
+        if (unionArea > 0.0 && intersectionArea >= 0.0)
+        {
+          return intersectionArea / unionArea;
+        }
+      }
+    }
+  }
+
+  return nullValue();
+}
+
+}