From bb611272543fce8c6b21735c383c954421bf130c Mon Sep 17 00:00:00 2001
From: Laurent Rineau <laurent.rineau@cgal.org>
Date: Wed, 21 May 2025 15:34:35 +0200
Subject: [PATCH] always use read_polygon_mesh and write_MEDIT

---
 .../ccdt_3_after_autorefinement.cpp           | 33 ++++++++++---------
 .../ccdt_3_check_preconditions.cpp            |  9 +++--
 .../ccdt_3_from_soup_fpmap.cpp                | 21 +++++++-----
 .../ccdt_3_preprocessing.cpp                  | 27 +++++++--------
 ...g_constrained_Delaunay_triangulation_3.cpp |  7 ++--
 ...trained_Delaunay_triangulation_3_fpmap.cpp |  6 ++--
 ...ned_Delaunay_triangulation_3_from_soup.cpp |  9 +++--
 7 files changed, 65 insertions(+), 47 deletions(-)

diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_after_autorefinement.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_after_autorefinement.cpp
index 8fe78adb679..4d926f25bef 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_after_autorefinement.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_after_autorefinement.cpp
@@ -1,12 +1,13 @@
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 
-#include "CGAL/Polygon_mesh_processing/polygon_soup_self_intersections.h"
+#include <CGAL/IO/polygon_mesh_io.h>
+#include <CGAL/IO/write_MEDIT.h>
 #include <CGAL/Polygon_mesh_processing/autorefinement.h>
+#include <CGAL/Polygon_mesh_processing/polygon_soup_self_intersections.h>
 #include <CGAL/Polygon_mesh_processing/self_intersections.h>
 #include <CGAL/Surface_mesh/Surface_mesh.h>
-#include <CGAL/make_conforming_constrained_Delaunay_triangulation_3.h>
-
 #include <CGAL/draw_constrained_triangulation_3.h>
+#include <CGAL/make_conforming_constrained_Delaunay_triangulation_3.h>
 
 using K = CGAL::Exact_predicates_inexact_constructions_kernel;
 using Point = K::Point_3;
@@ -20,8 +21,7 @@ int main(int argc, char* argv[])
                        : CGAL::data_file_path("meshes/spheres_intersecting.off");
 
   CGAL::Surface_mesh<K::Point_3> mesh;
-  std::ifstream in(filename);
-  if(!in || !(in >> mesh)) {
+  if(!CGAL::IO::read_polygon_mesh(filename, mesh)) {
     std::cerr << "Error: cannot read file " << filename << std::endl;
     return EXIT_FAILURE;
   }
@@ -29,6 +29,8 @@ int main(int argc, char* argv[])
   std::cout << "Number of facets in " << filename << ": "
     << mesh.number_of_faces() << "\n";
 
+  CGAL::Conforming_constrained_Delaunay_triangulation_3<K> ccdt;
+
   if(PMP::does_self_intersect(mesh))
   {
     std::cout << "Mesh self-intersects, performing autorefine...\n";
@@ -46,22 +48,21 @@ int main(int argc, char* argv[])
       return EXIT_FAILURE;
     }
 
-    auto ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(points, polygons);
+    ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(points, polygons);
 
-    std::cout << "Number of constrained facets in the CDT: "
-              << ccdt.number_of_constrained_facets() << '\n';
-
-    CGAL::draw(ccdt);
   }
   else
   {
-    auto ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(mesh);
-
-    std::cout << "Number of constrained facets in the CDT: "
-              << ccdt.number_of_constrained_facets() << '\n';
-
-    CGAL::draw(ccdt);
+    ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(mesh);
   }
+  std::cout << "Number of constrained facets in the CDT: "
+            << ccdt.number_of_constrained_facets() << '\n';
+
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
+  CGAL::IO::write_MEDIT(ofs, ccdt);
+
+  CGAL::draw(ccdt);
 
   return EXIT_SUCCESS;
 }
diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_check_preconditions.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_check_preconditions.cpp
index b3acadde9e0..5d1daff7d42 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_check_preconditions.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_check_preconditions.cpp
@@ -1,5 +1,7 @@
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 
+#include <CGAL/IO/polygon_mesh_io.h>
+#include <CGAL/IO/write_MEDIT.h>
 #include <CGAL/Surface_mesh/Surface_mesh.h>
 #include <CGAL/make_conforming_constrained_Delaunay_triangulation_3.h>
 
@@ -17,8 +19,7 @@ int main(int argc, char* argv[])
                        : CGAL::data_file_path("meshes/mpi_and_sphere.off");
 
   CGAL::Surface_mesh<K::Point_3> mesh;
-  std::ifstream in(filename);
-  if(!in || !(in >> mesh)) {
+  if(!CGAL::IO::read_polygon_mesh(filename, mesh)) {
     std::cerr << "Error: cannot read file " << filename << std::endl;
     return EXIT_FAILURE;
   }
@@ -39,6 +40,10 @@ int main(int argc, char* argv[])
   std::cout << "Number of constrained facets in the CDT: "
             << ccdt.number_of_constrained_facets() << '\n';
 
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
+  CGAL::IO::write_MEDIT(ofs, ccdt);
+
   CGAL::draw(ccdt);
 
   return EXIT_SUCCESS;
diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_from_soup_fpmap.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_from_soup_fpmap.cpp
index 38ab2f31849..66ae47f6796 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_from_soup_fpmap.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_from_soup_fpmap.cpp
@@ -1,9 +1,11 @@
-#include <CGAL/draw_constrained_triangulation_3.h>
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
-#include <CGAL/make_conforming_constrained_Delaunay_triangulation_3.h>
+#include <CGAL/IO/polygon_mesh_io.h>
+#include <CGAL/IO/write_MEDIT.h>
 #include <CGAL/Polygon_mesh_processing/connected_components.h>
 #include <CGAL/Polygon_mesh_processing/polygon_mesh_to_polygon_soup.h>
 #include <CGAL/Surface_mesh/Surface_mesh.h>
+#include <CGAL/draw_constrained_triangulation_3.h>
+#include <CGAL/make_conforming_constrained_Delaunay_triangulation_3.h>
 
 #include <algorithm>
 #include <vector>
@@ -17,13 +19,10 @@ namespace PMP = CGAL::Polygon_mesh_processing;
 
 int main(int argc, char* argv[])
 {
-  CGAL::Surface_mesh<K::Point_3> mesh;
-  std::vector<K::Point_3> points;
-  std::vector<std::vector<std::size_t>> polygons;
-
   auto filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/cubes_one_patch_id_per_cc.off");
-  std::ifstream in(filename);
-  if(!in || !(in >> mesh)) {
+
+  CGAL::Surface_mesh<K::Point_3> mesh;
+    if(!CGAL::IO::read_polygon_mesh(filename, mesh)) {
     std::cerr << "Error: cannot read file " << filename << std::endl;
     return EXIT_FAILURE;
   }
@@ -41,6 +40,9 @@ int main(int argc, char* argv[])
                                   return fpmap[f1] < fpmap[f2];
                                 })] + 1
             << std::endl;
+
+  std::vector<K::Point_3> points;
+  std::vector<std::vector<std::size_t>> polygons;
   PMP::polygon_mesh_to_polygon_soup(mesh, points, polygons);
 
   auto polygon_to_patch_id = [&](std::size_t i) {
@@ -56,6 +58,9 @@ int main(int argc, char* argv[])
             << "Number of constrained facets in the CDT: "
             << ccdt.number_of_constrained_facets() << '\n';
 
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
+  CGAL::IO::write_MEDIT(ofs, ccdt);
 
   CGAL::draw(ccdt);
 
diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_preprocessing.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_preprocessing.cpp
index 3532baa266e..d2367e7e1e0 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_preprocessing.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/ccdt_3_preprocessing.cpp
@@ -1,5 +1,6 @@
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 
+#include <CGAL/IO/write_MEDIT.h>
 #include <CGAL/Surface_mesh/Surface_mesh.h>
 #include <CGAL/Polygon_mesh_processing/self_intersections.h>
 #include <CGAL/Polygon_mesh_processing/autorefinement.h>
@@ -22,8 +23,7 @@ int main(int argc, char* argv[])
                        : CGAL::data_file_path("meshes/mpi_and_sphere.off");
 
   CGAL::Surface_mesh<K::Point_3> mesh;
-  std::ifstream in(filename);
-  if(!in || !(in >> mesh)) {
+  if(!CGAL::IO::read_polygon_mesh(filename, mesh)) {
     std::cerr << "Error: cannot read file " << filename << std::endl;
     return EXIT_FAILURE;
   }
@@ -52,6 +52,7 @@ int main(int argc, char* argv[])
     }
   }
 
+  CGAL::Conforming_constrained_Delaunay_triangulation_3<K> ccdt;
   if(triangle_mesh && PMP::does_self_intersect(mesh))
   {
     std::cout << "Mesh is a self-intersecting triangle mesh, perform autorefinement...\n";
@@ -64,25 +65,25 @@ int main(int argc, char* argv[])
     std::cout << "Number of facets after preprocessing: "
               << polygons.size() << "\n";
 
-    auto ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(points, polygons);
+    ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(points, polygons);
 
-    std::cout << "Number of constrained facets in the CDT: "
-              << ccdt.number_of_constrained_facets() << '\n';
-
-    CGAL::draw(ccdt);
   }
   else
   {
     std::cout << "Number of facets after preprocessing: "
               << mesh.number_of_faces() << "\n";
 
-    auto ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(mesh);
-
-    std::cout << "Number of constrained facets in the CDT: "
-              << ccdt.number_of_constrained_facets() << '\n';
-
-    CGAL::draw(ccdt);
+    ccdt = CGAL::make_conforming_constrained_Delaunay_triangulation_3(mesh);
   }
 
+  std::cout << "Number of constrained facets in the CDT: "
+            << ccdt.number_of_constrained_facets() << '\n';
+
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
+  CGAL::IO::write_MEDIT(ofs, ccdt);
+
+  CGAL::draw(ccdt);
+
   return EXIT_SUCCESS;
 }
diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3.cpp
index a6711bcba31..6cf56cc7bc7 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3.cpp
@@ -9,9 +9,9 @@ using K = CGAL::Exact_predicates_inexact_constructions_kernel;
 
 int main(int argc, char* argv[])
 {
-  CGAL::Surface_mesh<K::Point_3> mesh;
-
   auto filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/mpi.off");
+
+  CGAL::Surface_mesh<K::Point_3> mesh;
   if(!CGAL::IO::read_polygon_mesh(filename, mesh)) {
     std::cerr << "Error: cannot read file " << filename << std::endl;
     return EXIT_FAILURE;
@@ -27,7 +27,8 @@ int main(int argc, char* argv[])
             << "Number of constrained facets in the CDT: "
             << ccdt.number_of_constrained_facets() << '\n';
 
-  std::ofstream ofs("out.mesh");
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
   CGAL::IO::write_MEDIT(ofs, ccdt);
 
   CGAL::draw(ccdt);
diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_fpmap.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_fpmap.cpp
index 10708ca96ac..07a655da8ab 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_fpmap.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_fpmap.cpp
@@ -44,9 +44,9 @@ int main(int argc, char* argv[])
             << "Number of constrained facets in the CDT: "
             << ccdt.number_of_constrained_facets() << '\n';
 
-  std::ofstream out("ccdt.mesh");
-  CGAL::IO::write_MEDIT(out, ccdt);
-  out.close();
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
+  CGAL::IO::write_MEDIT(ofs, ccdt);
 
   return EXIT_SUCCESS;
 }
diff --git a/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_from_soup.cpp b/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_from_soup.cpp
index 368d8772778..cbe716e5efd 100644
--- a/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_from_soup.cpp
+++ b/Constrained_triangulation_3/examples/Constrained_triangulation_3/conforming_constrained_Delaunay_triangulation_3_from_soup.cpp
@@ -1,5 +1,6 @@
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 #include <CGAL/IO/polygon_soup_io.h>
+#include <CGAL/IO/write_MEDIT.h>
 #include <CGAL/draw_constrained_triangulation_3.h>
 #include <CGAL/make_conforming_constrained_Delaunay_triangulation_3.h>
 
@@ -9,10 +10,10 @@ using K = CGAL::Exact_predicates_inexact_constructions_kernel;
 
 int main(int argc, char* argv[])
 {
+  auto filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/cubes.off");
+
   std::vector<K::Point_3> points;
   std::vector<std::vector<std::size_t>> polygons;
-
-  auto filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/cubes.off");
   if(!CGAL::IO::read_polygon_soup(filename, points, polygons)) {
     std::cerr << "Error: cannot read file " << filename << std::endl;
     return EXIT_FAILURE;
@@ -28,6 +29,10 @@ int main(int argc, char* argv[])
             << "Number of constrained facets in the CDT: "
             << ccdt.number_of_constrained_facets() << '\n';
 
+  std::ofstream ofs(argc > 2 ? argv[2] : "out.mesh");
+  ofs.precision(17);
+  CGAL::IO::write_MEDIT(ofs, ccdt);
+
   CGAL::draw(ccdt);
 
   return EXIT_SUCCESS;