local feature size for point set processing

Point_set_processing_3/doc/Point_set_processing_3/Point_set_processing_3.txt

@@ -926,6 +926,18 @@ The following example reads a point set from a file, estimates the
 points that are on sharp edges:
 \cgalExample{Point_set_processing_3/edges_example.cpp}
 
+\section Point_set_processing_3LFSEstimation Local Feature Size Estimation
+
+The function `estimate_local_feature_size()` can estimate the local feature size for each point by giving a raw point set.
+
+The function will estimate the curvature and shape diameter. Then, the local feature size will be the minimum of the curvature radius and half of the shape diameter.
+
+\subsection Point_set_processing_3Example_LFS Example
+
+The following example reads a point set from a file, estimates the
+local feature size for each point:
+\cgalExample{Point_set_processing_3/lfs_example.cpp}
+
 
 \section Point_set_processing_3Structuring Structuring
 

Point_set_processing_3/doc/Point_set_processing_3/examples.txt

@@ -21,6 +21,7 @@
 \example Point_set_processing_3/bilateral_smooth_point_set_example.cpp
 \example Point_set_processing_3/edge_aware_upsample_point_set_example.cpp
 \example Point_set_processing_3/edges_example.cpp
+\example Point_set_processing_3/lfs_example.cpp
 \example Point_set_processing_3/structuring_example.cpp
 \example Point_set_processing_3/callback_example.cpp
 */

Point_set_processing_3/examples/Point_set_processing_3/lfs_example.cpp

@@ -0,0 +1,49 @@
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+#include <CGAL/estimate_lfs.h>
+#include <CGAL/IO/read_points.h>
+
+#include <vector>
+#include <utility> // defines std::pair
+
+
+// types
+typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
+typedef Kernel::FT FT;
+typedef Kernel::Point_3 Point;
+typedef Kernel::Vector_3 Vector;
+
+// Point with normal vector stored in a std::pair.
+typedef std::pair<Point, Vector> Point_with_normal;
+
+// Concurrency
+typedef CGAL::Parallel_if_available_tag Concurrency_tag;
+
+
+int main(void)
+{
+
+  // read xyz
+  const std::string filename = "./frog.xyz";
+
+  std::vector<Point_with_normal> points;
+  if(!CGAL::IO::read_points(filename,
+                            std::back_inserter(points),
+                            CGAL::parameters::point_map(CGAL::First_of_pair_property_map<Point_with_normal>())))
+  {
+    std::cerr << "Error: cannot read file " << filename<< std::endl;
+    return EXIT_FAILURE;
+  }
+
+  unsigned int jet_k = 24;
+  std::size_t N_rays = 60;
+  FT apex_angle = 30;
+  std::vector<FT> lfses = CGAL::estimate_local_feature_size<Concurrency_tag>(points, jet_k, N_rays, apex_angle,
+    CGAL::parameters::point_map(CGAL::First_of_pair_property_map<Point_with_normal>())
+                                                .normal_map(CGAL::Second_of_pair_property_map<Point_with_normal>()));
+
+  for (const auto &lfs : lfses)
+    std::cerr << lfs << "\n";
+
+
+  return EXIT_SUCCESS;
+}