Small feature: add function insert_in_hole to Triangulation_data_structure_2. Contains documentation and test.

TDS_2/doc/TDS_2/Concepts/TriangulationDataStructure_2.h

@@ -550,6 +550,31 @@ void dim_down(Face_handle f, int i);
 /// @{
 
 
+/*!
+\cgalModifBegin
+creates a new vertex `v` and uses it to star the hole 
+described by the sequence of edges `[edge_begin, edge_end]`.
+The pre-existing faces in the hole are destroyed.
+Returns a handle to the vertex `v`.
+
+\pre The sequence of edges `[edge_begin, edge_end]` is oriented counter-clockwise.
+\cgalModifEnd
+*/
+template< class EdgeIt >
+Vertex_handle insert_in_hole(EdgeIt edge_begin, EdgeIt edge_end);
+
+/*!
+\cgalModifBegin
+uses the vertex `v` to star the hole described by the sequence
+of edges `[edge_begin, edge_end]`. The pre-existing faces in the hole are destroyed. 
+
+\pre The sequence of edges `[edge_begin, edge_end]` is oriented counter-clockwise.
+\cgalModifEnd
+*/
+template< class EdgeIt >
+void insert_in_hole(Vertex_handle v, EdgeIt edge_begin, EdgeIt edge_end); 
+
+
 /*!
 creates a new vertex `v` and use it to star the hole 
 whose boundary is described by the sequence of edges `[edge_begin, edge_end)`. Returns a handle to the vertex. 

TDS_2/include/CGAL/Triangulation_data_structure_2.h

@@ -428,6 +428,97 @@ public:
 
   // template members definition
 public:
+
+  /************* START OF MODIFICATIONS (iiordanov) ***************/
+
+
+  /* 
+   * Creates a new vertex new_v and uses it to star the hole described
+   * by the sequence of edges [edge_begin, edge_end]. The pre-existing
+   * faces in the hole are destroyed.
+   *
+   * Prerequisite: the sequence [edge_begin, edge_end] is oriented
+   * counter-clockwise.
+   */
+
+  template< class EdgeIt >
+  Vertex_handle insert_in_hole(EdgeIt edge_begin, EdgeIt edge_end) 
+  {
+    Vertex_handle new_v = create_vertex();
+    insert_in_hole(new_v, edge_begin, edge_end);
+    return new_v;
+  }
+
+
+  /* 
+   * Uses the vertex v to star the hole described by the sequence 
+   * of edges [edge_begin, edge_end]. The pre-existing faces in 
+   * the hole are destroyed.
+   *
+   * Prerequisite: the sequence [edge_begin, edge_end] is oriented
+   * counter-clockwise.
+   */
+  template< class EdgeIt >
+  void insert_in_hole(Vertex_handle v, EdgeIt edge_begin, EdgeIt edge_end) 
+  {
+
+    // Keep new faces in a vector
+    std::vector<Face_handle> new_faces;
+
+    // Exploit std::set functionality to keep unique old faces
+    std::set<Face_handle> old;
+
+    for (EdgeIt it = edge_begin; it != edge_end; it++) {
+      Face_handle fh = (*it).first;
+      int i = (*it).second;
+
+      old.insert(fh);
+
+      //          v
+      //          .
+      //         / \
+      //        /   \
+      //       /     \
+      //      / new_f \
+      //  v1 /_________\ v2
+      //     \         /
+      //      \  nf   /
+      //       \     /
+      //        \   /
+      //         \ /
+      //          *
+      //     nf->vertex(j)     
+  
+      Vertex_handle v1 = fh->vertex(ccw(i));
+      Vertex_handle v2 = fh->vertex(cw(i));
+
+      Face_handle nf = fh->neighbor(i);
+      int j = mirror_index(fh, i);
+
+      Face_handle new_f = create_face(v, v1, v2);
+      set_adjacency(new_f, 0, nf, j);
+      new_faces.push_back(new_f);
+    }
+
+    // Set adjacency for the new faces
+    for (int i = 0; i < new_faces.size() - 1; i++) {
+      set_adjacency(new_faces[i], 1, new_faces[i+1], 2);
+    }
+    // The last one has to be treated separately
+    set_adjacency(new_faces[0], 2, new_faces[new_faces.size()-1], 1);
+
+    // Delete the old faces
+    for (typename std::set<Face_handle>::iterator it = old.begin(); it != old.end(); it++) {
+      delete_face(*it);
+    }
+
+    // Set the new vertex to point at the first new face (arbitrarily)
+    v->set_face(new_faces[0]);
+  }
+
+  /************* END OF MODIFICATIONS (iiordanov) ***************/
+
+
   template< class EdgeIt>
   Vertex_handle star_hole(EdgeIt edge_begin, EdgeIt edge_end)
   // creates a new vertex 

TDS_2/test/TDS_2/include/CGAL/_test_cls_tds_2.h

@@ -128,7 +128,6 @@ _test_cls_tds_2( const Tds &)
   assert(tds3.dimension()== 1);
   assert(tds3.number_of_vertices() == 4);
   assert(tds3.is_valid() );
-
  
   Vertex_handle w4 = tds4.insert_first();
   Vertex_handle v4_1 = tds4.insert_second();
@@ -187,6 +186,41 @@ _test_cls_tds_2( const Tds &)
   u4 = tds4.star_hole(hole);
   tds4.remove_degree_3(u4);
 
+
+  // insert_in_hole
+  // Count also the faces with the vertex at infinity! 
+  //
+  //  1 |------| 3     1 |------| 3
+  //    |\     |         |\    /|
+  //    | \    |         | \ 4/ |
+  //    |  \   |   -->   |  \/  |
+  //    |   \  |         |  /\  |
+  //    |    \ |         | /  \ |
+  //    |     \|         |/    \|
+  //  2 |------| 0     2 |------| 0
+  // 
+  // 
+   
+  std::cout << "    insert_in_hole" << std::endl;
+  Tds td45;
+  Vertex_handle v045 = td45.insert_first();
+  Vertex_handle v145 = td45.insert_second();
+  Vertex_handle v245 = td45.insert_dim_up(v045, true);
+  Vertex_handle v345 = td45.insert_dim_up(v045, true);
+
+  assert(td45.is_valid() && td45.number_of_vertices() == 4 && td45.number_of_faces() == 4);
+
+  Face_iterator fi = td45.faces_begin();
+  std::vector<Edge> vhole;
+  vhole.push_back( Edge(  fi, 2) );
+  vhole.push_back( Edge(  fi, 0) );
+  vhole.push_back( Edge(++fi, 1) );
+  vhole.push_back( Edge(  fi, 2) );
+
+  Vertex_handle nv45 = td45.insert_in_hole(vhole.begin(), vhole.end());
+
+  assert(td45.is_valid() && td45.number_of_vertices() == 5 && td45.number_of_faces() == 6);
+
   // dim_down
   std::cout << "    dim_down" << std::endl;
   Tds td5;