From 5b6b521ca89bd37b5c5bd67aef07a659dcef58f7 Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Tue, 15 Mar 2022 17:45:41 +0100
Subject: [PATCH] Deal with write_VTU()

---
 Mesh_2/doc/Mesh_2/CGAL/IO/write_VTU.h | 23 +++++++++++
 Mesh_2/include/CGAL/IO/write_VTU.h    | 56 +++++++++++++++++----------
 2 files changed, 58 insertions(+), 21 deletions(-)

diff --git a/Mesh_2/doc/Mesh_2/CGAL/IO/write_VTU.h b/Mesh_2/doc/Mesh_2/CGAL/IO/write_VTU.h
index 9b2b778c32e..e42e5c784d5 100644
--- a/Mesh_2/doc/Mesh_2/CGAL/IO/write_VTU.h
+++ b/Mesh_2/doc/Mesh_2/CGAL/IO/write_VTU.h
@@ -17,4 +17,27 @@ template <class CDT>
 void write_VTU(std::ostream& os,
                const CDT& tr,
                IO::Mode mode = IO::BINARY);
+
+
+//!\ingroup PkgMesh2IO
+//! \brief writes the faces of a domain and its constrained edges embedded in
+//! a 2D constrained Delaunay triangulation using the `PolyData` XML
+//! format.
+  //! The faces output are those for which `get(ipm, f)` returns
+  //! `true` where `f`is a  `CDT::Face_handle`,
+//! the edges are those for which `ConstrainedTriangulationFaceBase_2::is_constrained()` returns `true`.
+//! \tparam CDT a `Constrained_Delaunay_triangulation_2` with face type model of `DelaunayMeshFaceBase_2`.
+//!
+//! \param os the stream used for writing.
+//! \param tr the triangulated domain to be written.
+//! \param mode decides if the data should be written in binary (`BINARY`)
+//!             or in \ascii (`ASCII`).
+//!
+template <class CDT, typename InDomainPmap>
+void write_VTU(std::ostream& os,
+               const CDT& tr,
+               InDomainPmap ipm,
+               IO::Mode mode = IO::BINARY);
+
+
 } }
diff --git a/Mesh_2/include/CGAL/IO/write_VTU.h b/Mesh_2/include/CGAL/IO/write_VTU.h
index de6a0a313bd..56edc191afe 100644
--- a/Mesh_2/include/CGAL/IO/write_VTU.h
+++ b/Mesh_2/include/CGAL/IO/write_VTU.h
@@ -35,10 +35,11 @@ namespace internal {
 
 // writes the cells tags before binary data is appended
 
-template <class CDT>
+  template <class CDT, class InDomainPmap>
 void
 write_cells_tag_2(std::ostream& os,
                   const CDT & tr,
+                  InDomainPmap in_domain,
                   std::size_t number_of_triangles,
                   std::map<typename CDT::Vertex_handle, std::size_t> & V,
                   bool binary,
@@ -74,12 +75,12 @@ write_cells_tag_2(std::ostream& os,
             end = tr.finite_faces_end();
           fit != end; ++fit)
       {
-      if(fit->is_in_domain())
-      {
-        os << V[fit->vertex(0)] << " ";
-        os << V[fit->vertex(2)] << " ";
-        os << V[fit->vertex(1)] << " ";
-      }
+        if(get(in_domain, fit))
+          {
+            os << V[fit->vertex(0)] << " ";
+            os << V[fit->vertex(2)] << " ";
+            os << V[fit->vertex(1)] << " ";
+          }
     }
     for(typename CDT::Constrained_edges_iterator
           cei = tr.constrained_edges_begin(),
@@ -114,7 +115,7 @@ write_cells_tag_2(std::ostream& os,
         fit != tr.finite_faces_end() ;
         ++fit )
     {
-      if(fit->is_in_domain())
+      if(get(in_domain, fit))
       {
         cells_offset += 3;
         os << cells_offset << " ";
@@ -149,7 +150,7 @@ write_cells_tag_2(std::ostream& os,
         fit != tr.finite_faces_end() ;
         ++fit )
     {
-      if(fit->is_in_domain())
+      if(get(in_domain, fit))
       {
         os << "5 ";
       }
@@ -166,10 +167,11 @@ write_cells_tag_2(std::ostream& os,
 }
 
 // writes the cells appended data at the end of the .vtu file
-template <class CDT>
+  template <class CDT, class InDomainPmap>
 void
 write_cells_2(std::ostream& os,
               const CDT & tr,
+              InDomainPmap in_domain,
               std::size_t number_of_triangles,
               std::map<typename CDT::Vertex_handle, std::size_t> & V)
 {
@@ -185,7 +187,7 @@ write_cells_2(std::ostream& os,
       end = tr.finite_faces_end();
       fit != end; ++fit)
   {
-    if(fit->is_in_domain())
+    if(get(in_domain, fit))
     {
       off += 3;
       offsets.push_back(off);
@@ -324,11 +326,12 @@ write_attributes_2(std::ostream& os,
   write_vector(os,att);
 }
 
-template <class CDT>
+template <class CDT, class InDomainPmap>
 void write_VTU_with_attributes(std::ostream& os,
-               const CDT& tr,
-               std::vector<std::pair<const char*, const std::vector<double>*> >& attributes,
-               Mode mode = BINARY)
+                               const CDT& tr,
+                               InDomainPmap in_domain,
+                               std::vector<std::pair<const char*, const std::vector<double>*> >& attributes,
+                               Mode mode = BINARY)
 {
   typedef typename CDT::Vertex_handle Vertex_handle;
   std::map<Vertex_handle, std::size_t> V;
@@ -355,14 +358,14 @@ void write_VTU_with_attributes(std::ostream& os,
       end = tr.finite_faces_end();
       fit != end; ++fit)
   {
-    if(fit->is_in_domain()) ++number_of_triangles;
+    if(get(in_domain, fit)) ++number_of_triangles;
   }
   os << "  <Piece NumberOfPoints=\"" << tr.number_of_vertices()
      << "\" NumberOfCells=\"" << number_of_triangles + std::distance(tr.constrained_edges_begin(), tr.constrained_edges_end()) << "\">\n";
   std::size_t offset = 0;
   const bool binary = (mode == BINARY);
   write_cdt_points_tag(os,tr,V,binary,offset);
-  write_cells_tag_2(os,tr,number_of_triangles, V,binary,offset);
+  write_cells_tag_2(os,tr, in_domain, number_of_triangles, V,binary,offset);
   if(attributes.empty())
       os << "    <CellData >\n";
   else
@@ -377,7 +380,7 @@ void write_VTU_with_attributes(std::ostream& os,
   if (binary) {
     os << "<AppendedData encoding=\"raw\">\n_";
     write_cdt_points(os,tr,V);  // write points before cells to fill the std::map V
-    write_cells_2(os,tr, number_of_triangles, V);
+    write_cells_2(os, tr, in_domain, number_of_triangles, V);
     for(std::size_t i = 0; i< attributes.size(); ++i)
       write_attributes_2(os, *attributes[i].second);
   }
@@ -386,15 +389,26 @@ void write_VTU_with_attributes(std::ostream& os,
 
 } // namespace internal
 
-template <class CDT>
+template <class CDT, class InDomainPmap>
+void write_VTU(std::ostream& os,
+               const CDT& tr,
+               InDomainPmap ipm,
+               Mode mode = BINARY)
+{
+  std::vector<std::pair<const char*, const std::vector<double>*> > dummy_atts;
+  internal::write_VTU_with_attributes(os, tr, ipm, dummy_atts, mode);
+}
+
+template <class CDT, class InDomainPmap>
 void write_VTU(std::ostream& os,
                const CDT& tr,
                Mode mode = BINARY)
 {
-  std::vector<std::pair<const char*, const std::vector<double>*> > dummy_atts;
-  internal::write_VTU_with_attributes(os, tr, dummy_atts, mode);
+  internal::In_domain<CDT> in_domain;
+  write_VTU(os, tr, in_domain, mode);
 }
 
+
 } // namespace IO
 
 #ifndef CGAL_NO_DEPRECATED_CODE