fix bug when curve have a joint endpoint + improvement of tests

.gitattributes

@@ -1370,6 +1370,7 @@ Envelope_2/doc_tex/Envelope_2/fig/min_diag.gif -text svneol=unset#image/gif
 Envelope_2/doc_tex/Envelope_2/fig/min_diag.pdf -text svneol=unset#application/pdf
 Envelope_2/examples/Envelope_2/ch_points.dat -text
 Envelope_2/test/Envelope_2/data/Europe.dat -text
+Envelope_2/test/Envelope_2/data/bug_r49069.dat -text
 Envelope_2/test/Envelope_2/data/onebig_100.dat -text
 Envelope_2/test/Envelope_2/data/random_500.dat -text
 Envelope_2/test/Envelope_2/data/segs_4.dat -text

Envelope_2/include/CGAL/Envelope_2/Env_divide_and_conquer_2.h

@@ -255,8 +255,9 @@ protected:
    * \param out_d The merged diagram.
    */
   void _merge_single_interval (Edge_const_handle e, 
+                               Edge_const_handle other_edge,
                                Vertex_const_handle v, bool v_exists,
-                               bool same_org,
+                               Comparison_result origin_of_v,
                                Envelope_diagram_1& out_d);
 
   /*!
@@ -267,13 +268,16 @@ protected:
    * \param is_leftmost2 Is it the leftmost edge in its diagram.
    * \param v The next vertex.
    * \param v_exists Whether such a vertex exists.
-   * \param org_v The origin of v: 1 if it is from e1, 2 if it is from e2.
+   * \param origin_of_v The origin of v: SMALLER if it is from e1, 
+   *                    otherwise it is from e2. EQUAL result means that
+   *                    both diagram have vertex at the same place (but v
+   *                    is still taken from e2.
    * \param out_d The merged diagram.
    */
   void _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
                              Edge_const_handle e2, bool is_leftmost2,
                              Vertex_const_handle v, bool v_exists,
-                             int org_v,
+                             Comparison_result origin_of_v,
                              Envelope_diagram_1& out_d);
 
   /*!

Envelope_2/include/CGAL/Envelope_2/Env_divide_and_conquer_2_impl.h

@@ -299,24 +299,33 @@ _merge_envelopes (const Envelope_diagram_1& d1,
       _merge_two_intervals (e1, is_leftmost1,
                             e2, is_leftmost2,
                             next_v, next_exists,
-                            (res_v == SMALLER) ? 1 : 2,
+                            res_v, out_d);
-                            out_d);
+      
     }
     else if (! e1->is_empty() && e2->is_empty())
     {
       // e1 is not empty but e2 is empty:
-      _merge_single_interval (e1,
+      _merge_single_interval (e1, e2,
                               next_v, next_exists,
-                              (res_v == SMALLER),
+                              res_v,
                               out_d);
     }
     else if (e1->is_empty() && ! e2->is_empty())
     {
       // e1 is empty and e2 is not empty:
-      _merge_single_interval (e2,
+      _merge_single_interval (e2, e1,
                               next_v, next_exists,
-                              (res_v != SMALLER),
+                              CGAL::opposite(res_v),
                               out_d);
+      
+/*       // Bug fix: */
+/*       // If (res_v == EQUAL) then the _merge_single_interval will not */
+/*       // add the curves from v1 to the set of curves of the newly created */
+/*       // vertex (rightmost vertex). We handle it here though there maybe  */
+/*       // a better design for this code. */
+/*       if (res_v == EQUAL) */
+/*         out_d.rightmost()->left()->add_curves  */
+/*           (v1->curves_begin(), v1->curves_end()); */
     }
     else
     {
@@ -324,7 +333,17 @@ _merge_envelopes (const Envelope_diagram_1& d1,
       if (next_exists)
       {
         Vertex_handle  new_v = _append_vertex (out_d, next_v->point(), e1);
-        new_v->add_curves (next_v->curves_begin(), next_v->curves_end());
+        switch(res_v)
+        {
+        case SMALLER:
+          new_v->add_curves (v1->curves_begin(), v1->curves_end()); break;
+        case LARGER:
+          new_v->add_curves (v2->curves_begin(), v2->curves_end()); break;
+        case EQUAL:
+          new_v->add_curves (v1->curves_begin(), v1->curves_end());
+          new_v->add_curves (v2->curves_begin(), v2->curves_end());
+          break;
+        }
       }
     }
     
@@ -332,6 +351,7 @@ _merge_envelopes (const Envelope_diagram_1& d1,
     if (next_exists)
     {
       // Check if we should proceed on d1 or on d2.
+      // \todo: we do not need 3 cases, only two.
       if (res_v == SMALLER)
       {
         e1 = v1->right();
@@ -395,15 +415,10 @@ _compare_vertices (Vertex_const_handle v1,
   res = traits->compare_xy_2_object() (v1->point(),
                                        v2->point());
 
-  if ((env_type == LOWER && res == SMALLER) ||
+  // In case of upper envlope we take the opposite result
-      (env_type == UPPER && res == LARGER))
+  if (env_type == UPPER)
-    return (SMALLER);
+    return CGAL::opposite (res);
-  else if ((env_type == LOWER && res == LARGER) ||
+  return res;
-           (env_type == UPPER && res == SMALLER))
-    return (LARGER);
-  
-  // The two vertices represent equal points:
-  return (EQUAL);
 }
 
 // ---------------------------------------------------------------------------
@@ -412,9 +427,9 @@ _compare_vertices (Vertex_const_handle v1,
 //
 template <class Traits, class Diagram>
 void Envelope_divide_and_conquer_2<Traits,Diagram>::
-_merge_single_interval (Edge_const_handle e,
+_merge_single_interval (Edge_const_handle e, Edge_const_handle other_edge,
                         Vertex_const_handle v, bool v_exists,
-                        bool same_org,
+                        Comparison_result origin_of_v,
                         Envelope_diagram_1& out_d)
 {
   if (! v_exists)
@@ -427,7 +442,7 @@ _merge_single_interval (Edge_const_handle e,
   
   Vertex_handle      new_v;
   
-  if (same_org)
+  if (origin_of_v == SMALLER)
   {
     // The non-empty edge ends at v, so we simply insert it to out_d.
     new_v = _append_vertex (out_d, v->point(), e);
@@ -436,6 +451,15 @@ _merge_single_interval (Edge_const_handle e,
     return;
   }
 
+  if (origin_of_v == EQUAL) // the edges have vertices at the same place.
+  {
+    new_v = _append_vertex (out_d, v->point(), e);
+    new_v->add_curves (e->right()->curves_begin(), e->right()->curves_end());
+    new_v->add_curves (other_edge->right()->curves_begin(), 
+                       other_edge->right()->curves_end());
+    return;
+  }
+
   // If v is not on e, we should insert it to the merged diagram only if it
   // is below (or above, in case of an upper envelope) the curves of e.
   Comparison_result  res = traits->compare_y_at_x_2_object() (v->point(),
@@ -466,7 +490,7 @@ void Envelope_divide_and_conquer_2<Traits,Diagram>::
 _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1, 
                       Edge_const_handle e2, bool is_leftmost2,
                       Vertex_const_handle v, bool v_exists,
-                      int org_v,
+                      Comparison_result origin_of_v,
                       Envelope_diagram_1& out_d)
 {
   // Get the relative position of two curves associated with e1 and e2
@@ -514,8 +538,8 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
   // rightmost point in the merged diagram.
   std::list<CGAL::Object>           objects;
   CGAL::Object                      obj;
-  X_monotone_curve_2                icv;
+  X_monotone_curve_2                intersection_curve;
-  std::pair<Point_2, unsigned int>  ipt;
+  std::pair<Point_2, typename Traits::Multiplicity>  intersection_point;
   
   traits->intersect_2_object() (e1->curve(), e2->curve(),
                                 std::back_inserter(objects));
@@ -526,25 +550,25 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
     obj = objects.front();
     objects.pop_front();
     
-    if (CGAL::assign(ipt, obj))
+    if (CGAL::assign(intersection_point, obj))
     {
       // We have a simple intersection point.
       if (v_rm_exists &&
-          traits->compare_xy_2_object() (ipt.first, 
+          traits->compare_xy_2_object() (intersection_point.first, 
                                          v_rm->point()) != LARGER)
       {
         // The point is to the left of the current rightmost vertex in out_d,
         // so we skip it and continue examining the next intersections.
         // However, we update the last intersection point observed.
-        pu = ipt.first;
+        pu = intersection_point.first;
         pu_exists = true;
         continue;
       }
       
       if (v_exists)
       {
-        Comparison_result res = traits->compare_xy_2_object() (ipt.first, 
+        Comparison_result res = traits->compare_xy_2_object() 
-                                                               v->point());
+          (intersection_point.first, v->point());
         
         if (res == EQUAL)
           // v is an intersection points, so both curves are equal there:
@@ -576,9 +600,9 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
       CGAL_assertion (u_res != EQUAL);
       
       if (u_res == SMALLER)
-        new_v = _append_vertex (out_d, ipt.first, e1);
+        new_v = _append_vertex (out_d, intersection_point.first, e1);
       else
-        new_v = _append_vertex (out_d, ipt.first, e2);
+        new_v = _append_vertex (out_d, intersection_point.first, e2);
       
       // Note that the new vertex is incident to all curves in e1 and in e2.
       new_v->add_curves (e1->curves_begin(), e1->curves_end());
@@ -591,18 +615,19 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
       // Get the curve order immediately to the right of the intersection
       // point. Note that in case of even (non-zero) multiplicity the order
       // remains the same.
-      if (ipt.second % 2 == 1)
+      if (intersection_point.second % 2 == 1)
       {
         // Odd multiplicity: flip the current comparison result.
         u_res = CGAL::opposite (u_res);
       }
-      else if (ipt.second == 0)
+      else if (intersection_point.second == 0)
       {
         // The multiplicity is unknown, so we have to compare the curves to
         // the right of their intersection point.
-        u_res = traits->compare_y_at_x_right_2_object() (e1->curve(),
+        u_res = traits->compare_y_at_x_right_2_object() 
+          (e1->curve(),
            e2->curve(),
-                                                         ipt.first);
+           intersection_point.first);
         CGAL_assertion (u_res != EQUAL);
       }
     }
@@ -610,7 +635,7 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
     {
       // We have an x-monotone curve representing an overlap of the two
       // curves.
-      bool     assign_success = CGAL::assign (icv, obj);
+      bool     assign_success = CGAL::assign (intersection_curve, obj);
       
       CGAL_assertion (assign_success);
       if (! assign_success)
@@ -618,16 +643,16 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
 
       // Get the endpoints of the overlapping curves.
       const bool  has_left = 
-        (traits->parameter_space_in_x_2_object() (icv, ARR_MIN_END) == ARR_INTERIOR);
+        (traits->parameter_space_in_x_2_object() (intersection_curve, ARR_MIN_END) == ARR_INTERIOR);
       const bool  has_right = 
-        (traits->parameter_space_in_x_2_object() (icv, ARR_MAX_END) == ARR_INTERIOR);
+        (traits->parameter_space_in_x_2_object() (intersection_curve, ARR_MAX_END) == ARR_INTERIOR);
       Point_2     p1, p2;
       
       if (has_left)
-        p1 = traits->construct_min_vertex_2_object() (icv);
+        p1 = traits->construct_min_vertex_2_object() (intersection_curve);
       
       if (has_right)
-        p2 = traits->construct_max_vertex_2_object() (icv);
+        p2 = traits->construct_max_vertex_2_object() (intersection_curve);
       
       // Check if the overlapping curve is not relevant to our range.
       if (v_rm_exists && has_right &&
@@ -659,7 +684,7 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
         }
       }
       
-      // There is an overlap between the range [u, v] and icv.
+      // There is an overlap between the range [u, v] and intersection_curve.
       if (has_left && 
           (! v_rm_exists ||
            traits->compare_xy_2_object() (p1, 
@@ -684,9 +709,9 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
         CGAL_assertion (u_res != EQUAL);
 
         if (u_res == SMALLER)
-          new_v = _append_vertex (out_d, ipt.first, e1);
+          new_v = _append_vertex (out_d, intersection_point.first, e1);
         else
-          new_v = _append_vertex (out_d, ipt.first, e2);
+          new_v = _append_vertex (out_d, intersection_point.first, e2);
         
         // Note that the new vertex is incident to all curves in e1 and
         // in e2.
@@ -706,7 +731,7 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
         // Create an edge that represents the overlapping curve.
         Vertex_handle        new_v;
         
-        new_v = _append_vertex (out_d, ipt.first, e1);
+        new_v = _append_vertex (out_d, intersection_point.first, e1);
         new_v->left()->add_curves (e2->curves_begin(), e2->curves_end());
         
         new_v->add_curves (e1->curves_begin(), e1->curves_end());
@@ -734,6 +759,7 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
     
   } // End of the traversal over the intersection objects.
 
+
   // Handle the portion after the intersection objects.
   if (equal_at_v)
   {
@@ -750,9 +776,21 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
     if (u_res == EQUAL)
       new_v->left()->add_curves (e1->curves_begin(), e1->curves_end());
     
+    if (origin_of_v == EQUAL)
+    {
+      // If the vertices of the edge are the same, we have to get the 
+      // curves from there:
+      new_v->add_curves (e1->right()->curves_begin(), 
+                         e1->right()->curves_end());
+      new_v->add_curves (e2->right()->curves_begin(), 
+                         e2->right()->curves_end());
+    }
+    else
+    {
       // Note that the new vertex is incident to all curves in e1 and in e2.
       new_v->add_curves (e1->curves_begin(), e1->curves_end());
       new_v->add_curves (e2->curves_begin(), e2->curves_end());
+    }
     
     return;
   }
@@ -791,13 +829,27 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
     // The final part of the interval is taken from e1.
     Vertex_handle        new_v;
 
-    if (org_v == 1)
+    if (origin_of_v == SMALLER)
     {
       // In case v is also from e1, append it to the merged diagram.
       new_v = _append_vertex (out_d, v->point(), e1);
       new_v->add_curves (v->curves_begin(), v->curves_end());
     }
     else
+    {
+      // if origin_of_v is EQUAL then the two diagram have a vertex at
+      // exact same place.
+      if (origin_of_v == EQUAL)
+      {
+        new_v = _append_vertex (out_d, v->point(), e1);
+        new_v->add_curves (v->curves_begin(), v->curves_end());
+        
+        // adding the curves of the vertex of the first diagram (vertices are
+        // equal...)
+        new_v->add_curves (e1->right()->curves_begin(), 
+                           e1->right()->curves_end());
+      }
+      else
       {
         // If v is from e2, check if it below (or above, in case of an upper
         // envelope) cv1 to insert it.
@@ -817,16 +869,27 @@ _merge_two_intervals (Edge_const_handle e1, bool is_leftmost1,
           }
       }
     }
+  }
   else
   {
     // The final part of the interval is taken from e2.
     Vertex_handle        new_v;
 
-    if (org_v == 2)
+    if (origin_of_v != SMALLER)
     {
       // In case v is also from e2, append it to the merged diagram.
       new_v = _append_vertex (out_d, v->point(), e2);
       new_v->add_curves (v->curves_begin(), v->curves_end());
+      
+      // if origin_of_v is EQUAL then the two diagram have a vertex at
+      // exact same place.
+      if (origin_of_v == EQUAL)
+      {
+        // adding the curves of the vertex of the first diagram (vertices are
+        // equal...)
+        new_v->add_curves (e1->right()->curves_begin(), 
+                           e1->right()->curves_end());
+      }
     }
     else
     {

Envelope_2/test/Envelope_2/data/bug_r49069.dat

@@ -0,0 +1,14 @@
+9
+
+3 1 -1 1 
+2 0 1 0
+0 0 1 0 
+
+0 0 1 1
+0 0 1 -1
+
+4 0 3 1
+2 0 3 1 
+
+5 1 6 0
+5 -1 6 0

Envelope_2/test/Envelope_2/test_envelope_segments.cmd

@@ -2,3 +2,4 @@
 ./data/random_500.dat -i
 ./data/onebig_100.dat -i
 ./data/Europe.dat -d
+./data/bug_r49069.dat -i

Envelope_2/test/Envelope_2/test_envelope_segments.cpp

@@ -13,6 +13,7 @@
 
 #include <CGAL/Cartesian.h>
 #include <CGAL/Arr_segment_traits_2.h>
+#include <CGAL/Arr_curve_data_traits_2.h>
 #include <CGAL/Env_default_diagram_1.h>
 #include <CGAL/envelope_2.h>
 
@@ -23,11 +24,14 @@ using std::strcmp;
 
 typedef CGAL::Gmpq                                      NT;
 typedef CGAL::Cartesian<NT>                             Kernel;
-typedef CGAL::Arr_segment_traits_2<Kernel>              Traits_2;
+typedef CGAL::Arr_segment_traits_2<Kernel>              Segment_traits_2;
+typedef CGAL::Arr_curve_data_traits_2<Segment_traits_2, 
+                                      int>              Traits_2;
 typedef Traits_2::Point_2                               Point_2;
-typedef Traits_2::Curve_2                               Segment_2;
+typedef Segment_traits_2::Curve_2                       Segment_2;
+typedef Traits_2::Curve_2                               Curve_2;
 typedef CGAL::Env_default_diagram_1<Traits_2>           Diagram_1;
-typedef std::list<Segment_2>                            Segment_list;
+typedef std::list<Curve_2>                              Curve_list;
 
 enum Coord_input_format
 {
@@ -45,7 +49,7 @@ enum Coord_input_format
  */
 bool read_segments (const char *filename,
                     Coord_input_format format,
-                    Segment_list& segs)
+                    Curve_list& segs)
 {
   segs.clear();
 
@@ -94,13 +98,33 @@ bool read_segments (const char *filename,
     }
       
     seg = Segment_2 (Point_2 (x1, y1), Point_2 (x2, y2));
-    segs.push_back (seg);
+    segs.push_back (Curve_2(seg, segs.size()));
   }
   ifile.close();
 
   return (true);
 }
 
+/*!
+ * Check if a $x$-monotone curve with the same associated data as the input
+ * curve is in the given range.
+ * \param begin The begining of the range.
+ * \param end Passed-the-end iterator.
+ * \param c The curve, the data of which we are searching.
+ * \return True if we found an $x$-monotone curve with the same data.
+ */
+template<class I>
+bool find_curve(I begin, I end, const Curve_2 &c)
+{
+  while (begin != end)
+  {
+    if (begin->data() == c.data())
+      return true;
+    ++begin;
+  }
+  return false;
+}
+
 /*!
  * Check the envelope of a given set of segments.
  * \param segs The segments.
@@ -108,7 +132,7 @@ bool read_segments (const char *filename,
  * \param is_lower Does the diagram reprsent the lower or the upper envelope.
  * \return Whether the diagram structure is correct.
  */
-bool check_envelope (const Segment_list& segs,
+bool check_envelope (const Curve_list& segs,
                      const Diagram_1& diag,
                      bool is_lower)
 {
@@ -130,9 +154,10 @@ bool check_envelope (const Segment_list& segs,
   Point_2                        p_mid;
   CGAL::Comparison_result        res1, res2;
   CGAL::Comparison_result        y_res;
-  Segment_list::const_iterator   sit;
+  Curve_list::const_iterator     sit;
 
-  e = e->right()->right();
+  v = e->right();
+  e = v->right();
   while (e != diag.rightmost())
   {
     // Get the midpoint of the current edge.
@@ -143,15 +168,10 @@ bool check_envelope (const Segment_list& segs,
     {
       // Check if p_mid lies in the x-range of the current segment.
       res1 = compare_x (p_mid, min_ver(*sit));
-
-      if (res1 == CGAL::SMALLER)
-        continue;
-
       res2 = compare_x (p_mid, max_ver(*sit));
 
-      if (res2 == CGAL::LARGER)
+      if (res1 != CGAL::SMALLER && res2 != CGAL::LARGER)
-        continue;
+      {
-
         // Check the diagram edge.
         if (e->is_empty())
         {
@@ -180,8 +200,71 @@ bool check_envelope (const Segment_list& segs,
                       << std::endl;
             return (false);
           }
+          
+          // If it is equal, the segment should be in the diagram.
+          if (y_res == CGAL::EQUAL && 
+              find_curve(e->curves_begin(), e->curves_end(), *sit) == false)
+          {
+            std::cerr << "The edge (" << e->left()->point()
+                      << ") -> (" << e->right()->point() 
+                      << ") is associated with the segment ["
+                      << e->curve() << "], but the segment [" 
+                      << *sit << "] is not in the list of its curves."
+                      << std::endl;
+            return (false);
           }
         }
+      }
+
+
+      // Check if v lies in the x-range of the current segment.
+      res1 = compare_x (v->point(), min_ver(*sit));
+      res2 = compare_x (v->point(), max_ver(*sit));
+
+      if (res1 != CGAL::SMALLER && res2 != CGAL::LARGER)
+      {
+        // Check the diagram vertex.
+        if (v->number_of_curves() == 0)
+        {
+          // If v is in the x-range of the given segment, the current vertex
+          // cannot by empty.
+          std::cerr << "The vertex (" << v->point()
+                    << ") is empty, "
+                    << "but the segment [" << *sit << "] is defined over it."
+                    << std::endl;
+          return (false);
+        }
+        else
+        {
+          // Compare the segment with the segment associated with the edge.
+          y_res = comp_y_at_x (v->point(), *sit);
+          
+          // Check for violations of the diagram properties.
+          if ((is_lower && y_res == CGAL::LARGER) ||
+              (! is_lower && y_res == CGAL::SMALLER))
+          {
+            std::cerr << "The vertex (" << v->point()
+                      << ") and the segment [" 
+                      << *sit << "] violate the envelope properties."
+                      << std::endl;
+            return (false);
+          }
+          
+          // If it is equal, the segment should be in the diagram.
+          if (y_res == CGAL::EQUAL && 
+              find_curve(v->curves_begin(), v->curves_end(), *sit) == false)
+          {
+            std::cerr << "The vertex (" << v->point()
+                      << ") does not contain the segment [" 
+                      << *sit << "] in the list of its curves, but they have" 
+                      << " equal values."
+                      << std::endl;
+            return (false);
+          }
+        }
+      }
+
+    }
     v = e->right();
     e = v->right();
   }
@@ -196,28 +279,30 @@ bool check_envelope (const Segment_list& segs,
  */
 int main (int argc, char **argv)
 {
-  if (argc < 2)
+  if (argc % 2 == 0 || argc == 1)
   {
     std::cerr << "Usage: " << argv[0] 
               << "<input file> [ -q | -i | -d ]" << std::endl;
     return (1);
   }
 
+  int number_of_tests = (argc - 1) / 2;
+  for (int i = 0; i < number_of_tests; ++i)
+  {
+    std::cout << "Checking input file: " << argv[2*i + 1] << std::endl;
+    
     // Determine the input format.
     Coord_input_format   format = F_RATIONAL;
     
-  if (argc > 2)
+    if (strcmp (argv[2*i + 2], "-i") || strcmp (argv[2*i + 2], "-I"))
-  {
-    if (strcmp (argv[2], "-i") || strcmp (argv[2], "-I"))
       format = F_INTEGER;
-    else if (strcmp (argv[2], "-d") || strcmp (argv[2], "-D"))
+    else if (strcmp (argv[2*i + 2], "-d") || strcmp (argv[2*i + 2], "-D"))
       format = F_DOUBLE;
-  }
     
     // Read the input segments.
-  Segment_list   segments;
+    Curve_list   segments;
     
-  if (! read_segments (argv[1], format, segments))
+    if (! read_segments (argv[2*i + 1], format, segments))
       return (1);
     
     // Compute their lower envelope.
@@ -253,6 +338,6 @@ int main (int argc, char **argv)
     {
       std::cout << "The upper envelope is valid." << std::endl;
     }
-
+  }
   return (0);
 }