removal of Result_type and Unassigned_type from Region_growing

changed Primitive type declarations

Shape_detection/benchmark/Shape_detection/benchmark_region_growing_on_point_set_3.cpp

@@ -100,7 +100,7 @@ void benchmark_region_growing_on_point_set_3(
 
   // Run the algorithm.
   Timer timer;
-  Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
 
   timer.start();
   region_growing.detect(std::back_inserter(regions));

Shape_detection/doc/Shape_detection/Concepts/NeighborQuery.h

@@ -16,7 +16,7 @@ class NeighborQuery {
 
 public:
 
-  /// The reference type to the elements of the input range.
+  /// The reference type to the elements of the input range, e.g., a const_iterator of the input range.
   typedef unspecified_type Item;
 
   /*!

Shape_detection/doc/Shape_detection/Concepts/RegionType.h

@@ -5,8 +5,7 @@
 A concept that describes the set of methods used by the `CGAL::Shape_detection::Region_growing`
 to maintain a region.
 
-A region is represented by a set of `indices` of the items, which are included in
+A region is represented by a set items, which are included in this region.
-this region.
 
 \cgalHasModel
 - `CGAL::Shape_detection::Point_set::Least_squares_line_fit_region`
@@ -25,15 +24,12 @@ public:
   /// The parameters of the primitive covering the region.
   typedef unspecified_type Primitive;
 
-  /// The reference type to the elements of the input range.
+  /// The reference type to the elements of the input range, e.g., a const_iterator of the input range.
   typedef unspecified_type Item;
 
   // The region types is defined by a vector of Items.
   typedef std::vector<Item> Region;
 
-  /// The result type of the region growing provides the Primitive of each region with the Items combined in a `std::pair`.
-  typedef std::vector<std::pair<Primitive, Region> > Result_type;
-
   /*!
     a model of `ReadWritePropertyMap` whose key type is `Item`
     and value type is `std::size_t`. This map associates item of the input range
@@ -41,7 +37,6 @@ public:
   */
   typedef unspecified_type Region_index_map;
 
-
   /*!
     checks if the item `to`, which is a neighbor of the item
     `from`, can be added to the region represented by `region`.

Shape_detection/examples/Shape_detection/region_growing_lines_on_point_set_2.cpp

@@ -62,14 +62,14 @@ int main(int argc, char *argv[]) {
     point_set_2, neighbor_query, region_type);
 
   // Run the algorithm.
-  Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   std::cout << "* number of found lines: " << regions.size() << std::endl;
   assert(is_default_input && regions.size() == 72);
 
   // Save regions to a file.
   const std::string fullpath = (argc > 2 ? argv[2] : "lines_point_set_2.ply");
-  utils::save_point_regions_2<Kernel, Region_growing::Result_type, Point_map>(
+  utils::save_point_regions_2<Kernel, std::vector<typename Region_growing::Primitive_and_region>, Point_map>(
     regions, fullpath);
   return EXIT_SUCCESS;
 }

Shape_detection/examples/Shape_detection/region_growing_lines_on_polyline.cpp

@@ -65,14 +65,14 @@ int main(int argc, char *argv[]) {
     polyline_3, neighbor_query_3, region_type_3);
 
   // Run the algorithm on a 3D polyline.
-  Region_growing_3::Result_type regions;
+  std::vector<typename Region_growing_3::Primitive_and_region> regions;
   region_growing_3.detect(std::back_inserter(regions));
   std::cout << "* number of found 3D regions: " << regions.size() << std::endl;
   assert(is_default_input && regions.size() == 17);
 
   // Save 3D regions to a file.
   std::string fullpath = (argc > 2 ? argv[2] : "regions_polyline_3.ply");
-  utils::save_point_regions_3<Kernel, Region_growing_3::Result_type, Point_map_3>(
+  utils::save_point_regions_3<Kernel, std::vector<typename Region_growing_3::Primitive_and_region>, Point_map_3>(
     regions, fullpath);
 
   // Create the 2D polyline.
@@ -102,7 +102,7 @@ int main(int argc, char *argv[]) {
     polyline_2, neighbor_query_2, region_type_2);
 
   // Run the algorithm on a 2D polyline.
-  Region_growing_2::Result_type regions2;
+  std::vector<typename Region_growing_2::Primitive_and_region> regions2;
   region_growing_2.detect(std::back_inserter(regions2));
   std::cout << "* number of found 2D regions: " << regions2.size() << std::endl;
   assert(is_default_input && regions2.size() == 5);
@@ -114,7 +114,7 @@ int main(int argc, char *argv[]) {
   }
 
   fullpath = (argc > 2 ? argv[2] : "regions_polyline_2.ply");
-  utils::save_point_regions_2<Kernel, Region_growing_2::Result_type, Point_map_2>(
+  utils::save_point_regions_2<Kernel, std::vector<typename Region_growing_2::Primitive_and_region>, Point_map_2>(
     regions2, fullpath);
 
   return EXIT_SUCCESS;

Shape_detection/examples/Shape_detection/region_growing_lines_on_segment_set.cpp

@@ -50,7 +50,7 @@ int main(int argc, char *argv[]) {
   Plane_region plane_region(surface_mesh);
   RG_planes rg_planes(face_range, one_ring_query, plane_region);
 
-  RG_planes::Result_type regions;
+  std::vector<typename RG_planes::Primitive_and_region> regions;
   rg_planes.detect(std::back_inserter(regions));
   std::cout << "* number of found planar regions: " << regions.size() << std::endl;
   assert(is_default_input && regions.size() == 9);
@@ -72,13 +72,13 @@ int main(int argc, char *argv[]) {
   RG_lines rg_lines(
     segment_range, pgraph, line_region, line_sorting.ordered());
 
-  RG_lines::Result_type subregions;
+  std::vector<typename RG_lines::Primitive_and_region> subregions;
   rg_lines.detect(std::back_inserter(subregions));
   std::cout << "* number of found linear regions: " << subregions.size() << std::endl;
   assert(is_default_input && subregions.size() == 21);
 
   fullpath = (argc > 2 ? argv[2] : "subregions_sm.ply");
-  utils::save_segment_regions_3<Kernel, RG_lines::Result_type, Segment_map>(
+  utils::save_segment_regions_3<Kernel, std::vector<typename RG_lines::Primitive_and_region>, Segment_map>(
     subregions, fullpath, pgraph.segment_map());
 
   return EXIT_SUCCESS;

Shape_detection/examples/Shape_detection/region_growing_planes_on_polygon_mesh.cpp

@@ -73,7 +73,7 @@ int main(int argc, char *argv[]) {
     face_range, neighbor_query, region_type, sorting.ordered());
 
   // Run the algorithm.
-  Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   std::cout << "* number of found planes: " << regions.size() << std::endl;
   assert(is_default_input && regions.size() == 355);
@@ -87,7 +87,7 @@ int main(int argc, char *argv[]) {
       }
     }
 
-  Region_growing::Unassigned_type unassigned;
+  std::vector<typename Region_growing::Item> unassigned;
   region_growing.unassigned_items(std::back_inserter(unassigned));
 
   for (auto& item : unassigned) {

Shape_detection/examples/Shape_detection/region_growing_with_custom_classes.cpp

@@ -145,7 +145,7 @@ int main() {
     objects, neighbor_query, region_type);
 
   // Run the algorithm.
-  Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   std::cout << "* number of found regions: " << regions.size() << std::endl;
   assert(regions.size() == 2);

Shape_detection/include/CGAL/Shape_detection/Region_growing/Point_set/Least_squares_circle_fit_region.h

@@ -65,7 +65,6 @@ namespace Point_set {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Point_map = PointMap;
     using Normal_map = NormalMap;
@@ -78,25 +77,32 @@ namespace Point_set {
     using Item = typename InputRange::const_iterator;
     using Region = std::vector<Item>;
 
+#ifdef DOXYGEN_RUNNING
+    /// Primitive
+    using Primitive = struct {
+      typename GeomTraits::Point_2 center;
+      typename GeomTraits::FT radius;
+    };
+#else
     /// Primitive
     using Primitive = struct P {
-      P(const typename Traits::Point_2& c, typename Traits::FT r) : center(c), radius(r) {}
+      P(const typename GeomTraits::Point_2& c, typename GeomTraits::FT r) : center(c), radius(r) {}
-      typename Traits::Point_2 center;
-      typename Traits::FT radius;
-    };
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
 
+      typename GeomTraits::Point_2 center;
+      typename GeomTraits::FT radius;
+    };
+#endif
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;
     using Region_index_map = boost::associative_property_map<Region_unordered_map>;
     /// @}
 
   private:
-    using Point_2 = typename Traits::Point_2;
+    using Point_2 = typename GeomTraits::Point_2;
-    using Vector_2 = typename Traits::Vector_2;
+    using Vector_2 = typename GeomTraits::Vector_2;
 
-    using Squared_distance_2 = typename Traits::Compute_squared_distance_2;
+    using Squared_distance_2 = typename GeomTraits::Compute_squared_distance_2;
-    using Get_sqrt = internal::Get_sqrt<Traits>;
+    using Get_sqrt = internal::Get_sqrt<GeomTraits>;
     using Sqrt = typename Get_sqrt::Sqrt;
 
   public:
@@ -372,7 +378,7 @@ namespace Point_set {
     const Input_range& m_input_range;
     const Point_map m_point_map;
     const Normal_map m_normal_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     Region_unordered_map m_region_map;
 
     FT m_distance_threshold;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Point_set/Least_squares_cylinder_fit_region.h

@@ -65,7 +65,6 @@ namespace Point_set {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Point_map = PointMap;
     using Normal_map = NormalMap;
@@ -79,12 +78,19 @@ namespace Point_set {
     using Region = std::vector<Item>;
 
     /// Primitive
-    using Primitive = struct P {
+#ifdef DOXYGEN_RUNNING
-      P(const typename Traits::Line_3& a, const typename Traits::FT r) : axis(a), radius(r) {}
+    using Primitive = struct {
-      typename Traits::Line_3 axis;
+      typename GeomTraits::Line_3 axis;
-      typename Traits::FT radius;
+      typename GeomTraits::FT radius;
     };
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
+#else
+    using Primitive = struct P {
+      P(const typename GeomTraits::Line_3& a, const typename GeomTraits::FT r) : axis(a), radius(r) {}
+
+      typename GeomTraits::Line_3 axis;
+      typename GeomTraits::FT radius;
+    };
+#endif
 
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;
@@ -92,12 +98,12 @@ namespace Point_set {
     /// @}
 
   private:
-    using Point_3 = typename Traits::Point_3;
+    using Point_3 = typename GeomTraits::Point_3;
-    using Vector_3 = typename Traits::Vector_3;
+    using Vector_3 = typename GeomTraits::Vector_3;
-    using Line_3 = typename Traits::Line_3;
+    using Line_3 = typename GeomTraits::Line_3;
 
-    using Squared_distance_3 = typename Traits::Compute_squared_distance_3;
+    using Squared_distance_3 = typename GeomTraits::Compute_squared_distance_3;
-    using Get_sqrt = internal::Get_sqrt<Traits>;
+    using Get_sqrt = internal::Get_sqrt<GeomTraits>;
     using Sqrt = typename Get_sqrt::Sqrt;
 
   public:
@@ -381,7 +387,7 @@ namespace Point_set {
     const Input_range& m_input_range;
     const Point_map m_point_map;
     const Normal_map m_normal_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     Region_unordered_map m_region_map;
 
     FT m_distance_threshold;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Point_set/Least_squares_line_fit_region.h

@@ -65,7 +65,6 @@ namespace Point_set {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Point_map = PointMap;
     using Normal_map = NormalMap;
@@ -79,8 +78,7 @@ namespace Point_set {
     using Region = std::vector<Item>;
 
     /// Primitive
-    using Primitive = typename Traits::Line_2;
+    using Primitive = typename GeomTraits::Line_2;
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
 
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;
@@ -88,13 +86,13 @@ namespace Point_set {
     /// @}
 
   private:
-    using Point_2 = typename Traits::Point_2;
+    using Point_2 = typename GeomTraits::Point_2;
-    using Vector_2 = typename Traits::Vector_2;
+    using Vector_2 = typename GeomTraits::Vector_2;
-    using Line_2 = typename Traits::Line_2;
+    using Line_2 = typename GeomTraits::Line_2;
 
-    using Squared_length_2 = typename Traits::Compute_squared_length_2;
+    using Squared_length_2 = typename GeomTraits::Compute_squared_length_2;
-    using Squared_distance_2 = typename Traits::Compute_squared_distance_2;
+    using Squared_distance_2 = typename GeomTraits::Compute_squared_distance_2;
-    using Scalar_product_2 = typename Traits::Compute_scalar_product_2;
+    using Scalar_product_2 = typename GeomTraits::Compute_scalar_product_2;
 
   public:
     /// \name Initialization
@@ -202,7 +200,7 @@ namespace Point_set {
     /*!
       \brief implements `RegionType::region_index_map()`.
 
-      This function creates an empty property map that maps iterators on the input range `Item` to std::size_t.
+      This function creates an empty property map that maps iterators on the input range `Item` to `std::size_t`.
     */
     Region_index_map region_index_map() {
       return Region_index_map(m_region_map);
@@ -364,7 +362,7 @@ namespace Point_set {
     const Input_range& m_input_range;
     const Point_map m_point_map;
     const Normal_map m_normal_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     Region_unordered_map m_region_map;
 
     FT m_distance_threshold;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Point_set/Least_squares_plane_fit_region.h

@@ -65,7 +65,6 @@ namespace Point_set {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Point_map = PointMap;
     using Normal_map = NormalMap;
@@ -79,8 +78,7 @@ namespace Point_set {
     using Region = std::vector<Item>;
 
     /// Primitive
-    using Primitive = typename Traits::Plane_3;
+    using Primitive = typename GeomTraits::Plane_3;
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
 
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;
@@ -88,13 +86,13 @@ namespace Point_set {
     /// @}
 
   private:
-    using Point_3 = typename Traits::Point_3;
+    using Point_3 = typename GeomTraits::Point_3;
-    using Vector_3 = typename Traits::Vector_3;
+    using Vector_3 = typename GeomTraits::Vector_3;
-    using Plane_3 = typename Traits::Plane_3;
+    using Plane_3 = typename GeomTraits::Plane_3;
 
-    using Squared_length_3 = typename Traits::Compute_squared_length_3;
+    using Squared_length_3 = typename GeomTraits::Compute_squared_length_3;
-    using Squared_distance_3 = typename Traits::Compute_squared_distance_3;
+    using Squared_distance_3 = typename GeomTraits::Compute_squared_distance_3;
-    using Scalar_product_3 = typename Traits::Compute_scalar_product_3;
+    using Scalar_product_3 = typename GeomTraits::Compute_scalar_product_3;
 
   public:
     /// \name Initialization
@@ -363,7 +361,7 @@ namespace Point_set {
     const Input_range& m_input_range;
     const Point_map m_point_map;
     const Normal_map m_normal_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     Region_unordered_map m_region_map;
 
     FT m_distance_threshold;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Point_set/Least_squares_sphere_fit_region.h

@@ -65,7 +65,6 @@ g
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Point_map = PointMap;
     using Normal_map = NormalMap;
@@ -79,8 +78,7 @@ g
     using Region = std::vector<Item>;
 
     /// Primitive
-    using Primitive = typename Traits::Sphere_3;
+    using Primitive = typename GeomTraits::Sphere_3;
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
 
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;
@@ -88,12 +86,12 @@ g
     /// @}
 
   private:
-    using Point_3 = typename Traits::Point_3;
+    using Point_3 = typename GeomTraits::Point_3;
-    using Vector_3 = typename Traits::Vector_3;
+    using Vector_3 = typename GeomTraits::Vector_3;
-    using Sphere_3 = typename Traits::Sphere_3;
+    using Sphere_3 = typename GeomTraits::Sphere_3;
 
-    using Squared_distance_3 = typename Traits::Compute_squared_distance_3;
+    using Squared_distance_3 = typename GeomTraits::Compute_squared_distance_3;
-    using Get_sqrt = internal::Get_sqrt<Traits>;
+    using Get_sqrt = internal::Get_sqrt<GeomTraits>;
     using Sqrt = typename Get_sqrt::Sqrt;
 
   public:
@@ -370,7 +368,7 @@ g
     const Input_range& m_input_range;
     const Point_map m_point_map;
     const Normal_map m_normal_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     Region_unordered_map m_region_map;
 
     FT m_distance_threshold;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Polygon_mesh/Least_squares_plane_fit_region.h

@@ -62,7 +62,6 @@ namespace Polygon_mesh {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Face_graph = PolygonMesh;
     using Face_range = FaceRange;
     using Vertex_to_point_map = VertexToPointMap;
@@ -78,8 +77,7 @@ namespace Polygon_mesh {
     using Region = std::vector<Item>;
 
     /// Primitive
-    using Primitive = typename Traits::Plane_3;
+    using Primitive = typename GeomTraits::Plane_3;
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
 
     /// Region map
     using Region_index_map = typename boost::property_map<Face_graph, CGAL::dynamic_face_property_t<std::size_t> >::const_type;
@@ -87,14 +85,14 @@ namespace Polygon_mesh {
     /// @}
 
   private:
-    using Point_3 = typename Traits::Point_3;
+    using Point_3 = typename GeomTraits::Point_3;
-    using Vector_3 = typename Traits::Vector_3;
+    using Vector_3 = typename GeomTraits::Vector_3;
-    using Plane_3 = typename Traits::Plane_3;
+    using Plane_3 = typename GeomTraits::Plane_3;
 
-    using Squared_length_3 = typename Traits::Compute_squared_length_3;
+    using Squared_length_3 = typename GeomTraits::Compute_squared_length_3;
-    using Squared_distance_3 = typename Traits::Compute_squared_distance_3;
+    using Squared_distance_3 = typename GeomTraits::Compute_squared_distance_3;
-    using Scalar_product_3 = typename Traits::Compute_scalar_product_3;
+    using Scalar_product_3 = typename GeomTraits::Compute_scalar_product_3;
-    using Cross_product_3 = typename Traits::Construct_cross_product_vector_3;
+    using Cross_product_3 = typename GeomTraits::Construct_cross_product_vector_3;
 
   public:
     /// \name Initialization
@@ -358,7 +356,7 @@ namespace Polygon_mesh {
     const Face_graph& m_face_graph;
     const Face_range m_face_range;
     const Vertex_to_point_map m_vertex_to_point_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
 
     FT m_distance_threshold;
     FT m_cos_value_threshold;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Polygon_mesh/Least_squares_plane_fit_sorting.h

@@ -28,7 +28,7 @@ namespace Polygon_mesh {
 
     \brief Sorting of polygon mesh faces with respect to the local plane fit quality.
 
-    Indices of faces in a polygon mesh are sorted with respect to the quality of the
+    `Items` of faces in a polygon mesh are sorted with respect to the quality of the
     least squares plane fit applied to the vertices of incident faces of each face.
 
     \tparam GeomTraits
@@ -61,7 +61,6 @@ namespace Polygon_mesh {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Face_graph = PolygonMesh;
     using Neighbor_query = NeighborQuery;
     using Face_range = FaceRange;
@@ -77,7 +76,7 @@ namespace Polygon_mesh {
     /// @}
 
   private:
-    using FT = typename Traits::FT;
+    using FT = typename GeomTraits::FT;
     using Compare_scores = internal::Compare_scores<FT>;
 
   public:
@@ -180,7 +179,7 @@ namespace Polygon_mesh {
     Neighbor_query& m_neighbor_query;
     const Face_range m_face_range;
     const Vertex_to_point_map m_vertex_to_point_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     Seed_range m_ordered;
     std::vector<FT> m_scores;
 

Shape_detection/include/CGAL/Shape_detection/Region_growing/Polygon_mesh/One_ring_neighbor_query.h

@@ -54,7 +54,7 @@ namespace Polygon_mesh {
     /// \endcond
 
     /// Item type.
-    using Item = face_descriptor;
+    using Item = typename boost::graph_traits<PolygonMesh>::face_descriptor;
     using Region = std::vector<Item>;
 
     /// \name Initialization
@@ -82,7 +82,7 @@ namespace Polygon_mesh {
 
       This operator retrieves all faces,
       which are edge-adjacent to the face `query`.
-      These indices are returned in `neighbors`.
+      These `Items` are returned in `neighbors`.
 
       \param query
       `Item` of the query face

Shape_detection/include/CGAL/Shape_detection/Region_growing/Polyline/Least_squares_line_fit_region.h

@@ -80,9 +80,12 @@ namespace Polyline {
     /// Number type.
     typedef typename GeomTraits::FT FT;
 
-    /// Primitive
+    /// Primitive type depends on the dimension of the input data.
+#ifdef DOXYGEN_RUNNING
+    using Primitive = typename GeomTraits::Line_2 or typename GeomTraits::Line_3
+#else
     using Primitive = typename Polyline_traits::Line;
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
+#endif
 
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Polyline/Least_squares_line_fit_sorting.h

@@ -28,7 +28,7 @@ namespace Polyline {
 
     \brief Sorting of polyline vertices with respect to the local line fit quality.
 
-    Indices of input vertices are sorted with respect to the quality of the
+    `Items` of input vertices are sorted with respect to the quality of the
     least squares line fit applied to the incident vertices of each vertex.
 
     \tparam GeomTraits
@@ -56,7 +56,6 @@ namespace Polyline {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Neighbor_query = NeighborQuery;
     using Point_map = PointMap;
@@ -72,11 +71,11 @@ namespace Polyline {
     /// @}
 
   private:
-    using FT = typename Traits::FT;
+    using FT = typename GeomTraits::FT;
     using Polyline_traits = typename std::conditional<
-      std::is_same<typename Traits::Point_2, Point_type>::value,
+      std::is_same<typename GeomTraits::Point_2, Point_type>::value,
-      internal::Region_growing_traits_2<Traits>,
+      internal::Region_growing_traits_2<GeomTraits>,
-      internal::Region_growing_traits_3<Traits> >::type;
+      internal::Region_growing_traits_3<GeomTraits> >::type;
     using Compare_scores = internal::Compare_scores<FT>;
     using Dereference_pmap = internal::Dereference_property_map_adaptor<Item, PointMap>;
 
@@ -182,7 +181,7 @@ namespace Polyline {
     Neighbor_query& m_neighbor_query;
     const Point_map m_point_map;
     Dereference_pmap m_deref_pmap;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     const Polyline_traits m_polyline_traits;
     Seed_range m_ordered;
     std::vector<FT> m_scores;

Shape_detection/include/CGAL/Shape_detection/Region_growing/Polyline/One_ring_neighbor_query.h

@@ -31,7 +31,7 @@ namespace Polyline {
 
     \brief Direct neighbors connectivity in a polyline.
 
-    This class returns indices of the previous and next vertex
+    This class returns `Items` of the previous and next vertex
     in a polyline given as `InputRange.`
 
     \tparam GeomTraits

Shape_detection/include/CGAL/Shape_detection/Region_growing/Region_growing.h

@@ -72,10 +72,9 @@ namespace Shape_detection {
     /// Item type.
     using Item = typename RegionType::Item;
     using Region = std::vector<Item>;
-    using Unassigned_type = std::vector<Item>;
 
-    /// Result type
+    /// Primitive and region type
-    using Result_type = std::vector<std::pair<typename Region_type::Primitive, std::vector<Item> > >;
+    using Primitive_and_region = std::pair<typename Region_type::Primitive, Region>;
 
     /// Item to region property map.
     using Region_map = typename Region_type::Region_index_map;
@@ -174,19 +173,18 @@ namespace Shape_detection {
 
     /*!
       \brief runs the region growing algorithm and fills an output iterator
-      with the found regions.
+      with the fitted primitive and their region.
 
-      \tparam OutputIterator
+      \tparam PrimitiveAndRegionOutputIterator
-      a model of output iterator whose value type is `std::vector<std::size_t>`
+      a model of `OutputIterator` whose value type is `Primitive_and_region`
 
       \param regions
-      an output iterator to get for all items corresponding to each region its corresponding region.
+      an iterator of type `PrimitiveAndRegionOutputIterator`.
-      Elements put are of type `std::pair<Region_type::Primitive, std::vector<Item> >`.
 
       \return past-the-end position in the output sequence
     */
-    template<typename OutputIterator>
+    template<typename PrimitiveAndRegionOutputIterator>
-    OutputIterator detect(OutputIterator regions) {
+    PrimitiveAndRegionOutputIterator detect(PrimitiveAndRegionOutputIterator regions) {
       clear();
 
       Region region;
@@ -232,17 +230,16 @@ namespace Shape_detection {
     /*!
       \brief fills an output iterator with all unassigned items.
 
-      \tparam OutputIterator
+      \tparam ItemOutputIterator
-      a model of output iterator whose value type is `std::size_t`
+      a model of `OutputIterator` whose value type is `Item`
 
       \param output
-      an output iterator that stores indices of all items, which are not assigned
+      an iterator of type `PrimitiveAndRegionOutputIterator`.
-      to any region
 
       \return past-the-end position in the output sequence
     */
-    template<typename OutputIterator>
+    template<typename ItemOutputIterator>
-    OutputIterator unassigned_items(OutputIterator output) const {
+    ItemOutputIterator unassigned_items(ItemOutputIterator output) const {
       for (auto it = m_input_range.begin(); it != m_input_range.end(); it++) {
         Item i = internal::conditional_deref<typename Input_range::const_iterator, Item>()(it);
         if (!get(m_visited, i))

Shape_detection/include/CGAL/Shape_detection/Region_growing/Segment_set/Least_squares_line_fit_region.h

@@ -69,7 +69,6 @@ namespace Segment_set {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Segment_map = SegmentMap;
     using Segment_type = typename Segment_map::value_type;
@@ -82,9 +81,12 @@ namespace Segment_set {
     using Item = typename InputRange::const_iterator;
     using Region = std::vector<Item>;
 
-    /// Primitive
+    /// Primitive type depends on the dimension of the input data.
+#ifdef DOXYGEN_RUNNING
+    using Primitive = typename GeomTraits::Line_2 or typename GeomTraits::Line_3
+#else
     using Primitive = typename Segment_set_traits::Line;
-    using Result_type = std::vector<std::pair<Primitive, Region> >;
+#endif
 
     /// Region map
     using Region_unordered_map = boost::unordered_map<Item, std::size_t, internal::hash_item<Item> >;
@@ -340,7 +342,7 @@ namespace Segment_set {
   private:
     const Input_range& m_input_range;
     const Segment_map m_segment_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     const Segment_set_traits m_segment_set_traits;
     Region_unordered_map m_region_map;
 

Shape_detection/include/CGAL/Shape_detection/Region_growing/Segment_set/Least_squares_line_fit_sorting.h

@@ -56,7 +56,6 @@ namespace Segment_set {
     /// @{
 
     /// \cond SKIP_IN_MANUAL
-    using Traits = GeomTraits;
     using Input_range = InputRange;
     using Neighbor_query = NeighborQuery;
     using Segment_map = SegmentMap;
@@ -72,11 +71,11 @@ namespace Segment_set {
     /// @}
 
   private:
-    using FT = typename Traits::FT;
+    using FT = typename GeomTraits::FT;
     using Segment_set_traits = typename std::conditional<
-      std::is_same<typename Traits::Segment_2, Segment_type>::value,
+      std::is_same<typename GeomTraits::Segment_2, Segment_type>::value,
-      internal::Region_growing_traits_2<Traits>,
+      internal::Region_growing_traits_2<GeomTraits>,
-      internal::Region_growing_traits_3<Traits> >::type;
+      internal::Region_growing_traits_3<GeomTraits> >::type;
     using Compare_scores = internal::Compare_scores<FT>;
 
   public:
@@ -180,7 +179,7 @@ namespace Segment_set {
     const Input_range& m_input_range;
     Neighbor_query& m_neighbor_query;
     const Segment_map m_segment_map;
-    const Traits m_traits;
+    const GeomTraits m_traits;
     const Segment_set_traits m_segment_set_traits;
     Seed_range m_ordered;
     std::vector<FT> m_scores;

Shape_detection/test/Shape_detection/test_region_growing_basic.cpp

@@ -52,11 +52,11 @@ int main(int argc, char *argv[]) {
   Region_growing region_growing(
     input_range, neighbor_query, region_type);
 
-  Region_growing::Unassigned_type unassigned_points;
+  std::vector<typename Region_growing::Item> unassigned_points;
   region_growing.unassigned_items(std::back_inserter(unassigned_points));
   assert(unassigned_points.size() == 3634);
 
-  Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   const std::size_t num_regions = regions.size();
   assert(num_regions != 0);

Shape_detection/test/Shape_detection/test_region_growing_on_cube.cpp

@@ -81,13 +81,13 @@ bool test_region_growing_on_cube(int argc, char *argv[]) {
   Region_growing region_growing(
     face_range, neighbor_query, region_type, sorting.ordered());
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   assert(regions.size() == face_range.size());
   for (const auto& region : regions)
     assert(region_type.is_valid_region(region.second));
 
-  typename Region_growing::Unassigned_type unassigned_faces;
+  std::vector<typename Region_growing::Item> unassigned_faces;
   region_growing.unassigned_items(std::back_inserter(unassigned_faces));
   assert(unassigned_faces.size() == 0);
 

Shape_detection/test/Shape_detection/test_region_growing_on_degenerated_mesh.cpp

@@ -67,13 +67,13 @@ bool test_region_growing_on_degenerated_mesh(int argc, char *argv[]) {
   Region_growing region_growing(
     face_range, neighbor_query, region_type);
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   assert(regions.size() == 296);
   for (const auto& region : regions)
     assert(region_type.is_valid_region(region.second));
 
-  typename Region_growing::Unassigned_type unassigned_faces;
+  std::vector<typename Region_growing::Item> unassigned_faces;
   region_growing.unassigned_items(std::back_inserter(unassigned_faces));
   assert(unassigned_faces.size() == 509);
   return true;

Shape_detection/test/Shape_detection/test_region_growing_on_point_set_2.cpp

@@ -72,13 +72,13 @@ bool test_region_growing_on_point_set_2(int argc, char *argv[]) {
   Region_growing region_growing(
     input_range, neighbor_query, region_type);
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   assert(regions.size() == 72);
   for (const auto& region : regions)
     assert(region_type.is_valid_region(region.second));
 
-  typename Region_growing::Unassigned_type unassigned_points;
+  std::vector<typename Region_growing::Item> unassigned_points;
   region_growing.unassigned_items(std::back_inserter(unassigned_points));
   assert(unassigned_points.size() == 86);
   return true;

Shape_detection/test/Shape_detection/test_region_growing_on_point_set_2_with_sorting.cpp

@@ -79,7 +79,7 @@ bool test(int argc, char** argv, const std::string name, const std::size_t minr,
   Region_growing region_growing(
     input_range, neighbor_query, region_type, sorting.ordered());
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
 
   std::cout << "- num regions " + name + ": " << regions.size() << std::endl;
@@ -97,7 +97,7 @@ bool test(int argc, char** argv, const std::string name, const std::size_t minr,
       }
     }
 
-  typename Region_growing::Unassigned_type unassigned;
+  std::vector<typename Region_growing::Item> unassigned;
   region_growing.unassigned_items(std::back_inserter(unassigned));
 
   for (auto& item : unassigned) {

Shape_detection/test/Shape_detection/test_region_growing_on_point_set_3.cpp

@@ -69,13 +69,13 @@ bool test_region_growing_on_point_set_3(int argc, char *argv[]) {
   Region_growing region_growing(
     input_range, neighbor_query, region_type);
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   assert(regions.size() == 10);
   for (const auto& region : regions)
     assert(region_type.is_valid_region(region.second));
 
-  typename Region_growing::Unassigned_type unassigned_points;
+  std::vector<typename Region_growing::Item> unassigned_points;
   region_growing.unassigned_items(std::back_inserter(unassigned_points));
   assert(unassigned_points.size() == 246);
   return true;

Shape_detection/test/Shape_detection/test_region_growing_on_point_set_3_with_sorting.cpp

@@ -76,7 +76,7 @@ bool test(
   Region_growing region_growing(
     input_range, neighbor_query, region_type, sorting.ordered());
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   bool result = lambda_assertion(regions);
   assert(result);
@@ -91,7 +91,7 @@ bool test(
       }
     }
 
-  typename Region_growing::Unassigned_type unassigned;
+  std::vector<typename Region_growing::Item> unassigned;
   region_growing.unassigned_items(std::back_inserter(unassigned));
 
   for (auto& item : unassigned) {

Shape_detection/test/Shape_detection/test_region_growing_on_polygon_mesh.cpp

@@ -66,13 +66,13 @@ bool test_region_growing_on_polygon_mesh(int argc, char *argv[]) {
   Region_growing region_growing(
     face_range, neighbor_query, region_type);
 
-  typename Region_growing::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   assert(regions.size() == 414);
   for (const auto& region : regions)
     assert(region_type.is_valid_region(region.second));
 
-  typename Region_growing::Unassigned_type unassigned_faces;
+  std::vector<typename Region_growing::Item> unassigned_faces;
   region_growing.unassigned_items(std::back_inserter(unassigned_faces));
   assert(unassigned_faces.size() == 992);
   return true;

Shape_detection/test/Shape_detection/test_region_growing_on_polygon_mesh_with_sorting.cpp

@@ -73,7 +73,7 @@ int main(int argc, char *argv[]) {
   Region_growing region_growing(
     face_range, neighbor_query, region_type, sorting.ordered());
 
-  Region_growing::Result_type regions;
+  std::vector<Region_growing::Primitive_and_region> regions;
   region_growing.detect(std::back_inserter(regions));
   region_growing.clear();
   assert(regions.size() == 355);

Shape_detection/test/Shape_detection/test_region_growing_on_polyline.cpp

@@ -74,13 +74,13 @@ bool test_region_growing_on_polyline(int argc, char *argv[]) {
   Region_growing_3 region_growing_3(
     polyline_3, neighbor_query_3, region_type_3);
 
-  typename Region_growing_3::Result_type regions_3;
+  std::vector<typename Region_growing_3::Primitive_and_region> regions_3;
   region_growing_3.detect(std::back_inserter(regions_3));
   assert(regions_3.size() == 17);
   for (const auto& region : regions_3)
     assert(region_type_3.is_valid_region(region.second));
 
-  typename Region_growing_3::Unassigned_type unassigned_points;
+  std::vector<typename Region_growing_3::Item> unassigned_points;
   region_growing_3.unassigned_items(std::back_inserter(unassigned_points));
   assert(unassigned_points.size() == 0);
 
@@ -111,12 +111,12 @@ bool test_region_growing_on_polyline(int argc, char *argv[]) {
   Region_growing_2 region_growing_2(
     polyline_2, neighbor_query_2, region_type_2);
 
-  typename Region_growing_2::Result_type regions_2;
+  std::vector<typename Region_growing_2::Primitive_and_region> regions_2;
   region_growing_2.detect(std::back_inserter(regions_2));
   assert(regions_2.size() == 5);
   for (const auto& region : regions_2)
     assert(region_type_2.is_valid_region(region.second));
-  typename Region_growing_2::Unassigned_type unassigned_points2;
+  std::vector<typename Region_growing_2::Item> unassigned_points2;
   region_growing_2.unassigned_items(std::back_inserter(unassigned_points2));
   assert(unassigned_points2.size() == 0);
 

Shape_detection/test/Shape_detection/test_region_growing_on_polyline_with_sorting.cpp

@@ -79,11 +79,11 @@ int main(int argc, char *argv[]) {
   Region_growing_3 region_growing_3(
     polyline_3, neighbor_query_3, region_type_3, sorting_3.ordered());
 
-  Region_growing_3::Result_type regions3;
+  std::vector<Region_growing_3::Primitive_and_region> regions3;
   region_growing_3.detect(std::back_inserter(regions3));
   assert(regions3.size() == 16);
 
-  Region_growing_3::Unassigned_type unassigned_points;
+  std::vector<Region_growing_3::Item> unassigned_points;
   region_growing_3.unassigned_items(std::back_inserter(unassigned_points));
   assert(unassigned_points.size() == 1);
 
@@ -129,7 +129,7 @@ int main(int argc, char *argv[]) {
   Region_growing_2 region_growing_2(
     polyline_2, neighbor_query_2, region_type_2, sorting_2.ordered());
 
-  typename Region_growing_2::Result_type regions2;
+  std::vector<typename Region_growing_2::Primitive_and_region> regions2;
   region_growing_2.detect(std::back_inserter(regions2));
   assert(regions2.size() == 5);
   for (const auto& region : regions2)
@@ -145,7 +145,7 @@ int main(int argc, char *argv[]) {
       }
     }
 
-  Region_growing_2::Unassigned_type unassigned;
+  std::vector<Region_growing_2::Item> unassigned;
   region_growing_2.unassigned_items(std::back_inserter(unassigned));
 
   for (auto& item : unassigned) {
@@ -155,7 +155,7 @@ int main(int argc, char *argv[]) {
     }
   }
 
-  Region_growing_2::Unassigned_type unassigned2;
+  std::vector<Region_growing_2::Item> unassigned2;
   region_growing_2.unassigned_items(std::back_inserter(unassigned2));
   assert(unassigned2.size() == 0);
 

Shape_detection/test/Shape_detection/test_region_growing_strict.cpp

@@ -235,7 +235,7 @@ bool test_lines_segment_set_2_sorting() {
 
   Region_type region_type(segments);
 
-  typename Region_type::Result_type regions;
+  std::vector<typename Region_growing::Primitive_and_region> regions;
   Region_growing region_growing(
     segments, neighbor_query, region_type, sorting.ordered());
   region_growing.detect(std::back_inserter(regions));
@@ -299,7 +299,7 @@ bool test_lines_segment_set_3() {
     face_range, one_ring_query, plane_type, plane_sorting.ordered());
 
   assert(surface_mesh.number_of_faces() == 7320);
-  typename RG_planes::Result_type regions;
+  std::vector<typename RG_planes::Primitive_and_region> regions;
   rg_planes.detect(std::back_inserter(regions));
   assert(regions.size() == 9);
 
@@ -314,7 +314,7 @@ bool test_lines_segment_set_3() {
     segment_range, pgraph, CGAL::parameters::segment_map(pgraph.segment_map()));
   sorting.sort();
 
-  typename RG_lines::Result_type regions2;
+  std::vector<typename RG_lines::Primitive_and_region> regions2;
   RG_lines region_growing(
     segment_range, pgraph, region_type, sorting.ordered());
   region_growing.detect(std::back_inserter(regions2));