cgal/Packages/Triangulation_2/include/CGAL/Constrained_triangulation_p...

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// ============================================================================
//
// Copyright (c) 1997 The CGAL Consortium
//
// This software and related documentation is part of an INTERNAL release
// of the Computational Geometry Algorithms Library (CGAL). It is not
// intended for general use.
//
// ----------------------------------------------------------------------------
//
// release : $CGAL_Revision$
// release_date : $CGAL_Date$
//
// file : include/CGAL/Constrained_triangulation_plus_2.h
// source : $RCSfile$
// revision : $Revision$
// revision_date : $Date$
// author(s) : Mariette Yvinec
//
// coordinator : Mariette Yvinec < Mariette Yvinec@sophia.inria.fr>
//
// ============================================================================
#ifndef CGAL_CONSTRAINED_TRIANGULATION_PLUS_2_H
#define CGAL_CONSTRAINED_TRIANGULATION_PLUS_2_H
#include <CGAL/basic.h>
#include <CGAL/triangulation_assertions.h>
#include <CGAL/Triangulation_short_names_2.h>
#include <CGAL/Constraint_hierarchy_2.h>
CGAL_BEGIN_NAMESPACE
// Tr the base triangulation class
// Tr has to be Constrained or Constrained_Delaunay
// I_tag to tag the optional support of constriaint intersections
template < class Tr, class I_tag = Tag_false>
class Constrained_triangulation_plus_2
: public Tr
{
public:
typedef Tr Triangulation;
typedef I_tag Intersection_tag;
typedef typename Triangulation::Edge Edge;
typedef typename Triangulation::Vertex Vertex;
typedef typename Triangulation::Vertex_handle Vertex_handle;
typedef typename Triangulation::Face_handle Face_handle;
typedef typename Triangulation::Locate_type Locate_type;
typedef typename Triangulation::Line_face_circulator Line_face_circulator;
typedef typename Triangulation::Geom_traits Geom_traits;
typedef typename Geom_traits::Point_2 Point;
typedef typename Geom_traits::Segment_2 Segment;
typedef typename Triangulation::Constraint Constraint;
typedef typename Triangulation::List_edges List_edges;
typedef typename Triangulation::List_faces List_faces;
typedef typename Triangulation::List_vertices List_vertices;
typedef typename Triangulation::List_constraints List_constraints;
typedef Constraint_hierarchy_2<Vertex_handle, bool> Constraint_hierarchy;
protected:
Constraint_hierarchy hierarchy;
public:
Constrained_triangulation_plus_2(const Geom_traits& gt=Geom_traits())
: Triangulation() { }
// copy constructrue et effectation operateur a revoir
// Constrained_triangulation_plus_2(
// const Constrained_triangulation_plus_2& ct)
// : Constrained_triangulation(ct) {}
Constrained_triangulation_plus_2(List_constraints& lc,
const Geom_traits& gt=Geom_traits())
: Triangulation(gt)
{
typename List_constraints::iterator lcit=lc.begin();
for( ;lcit != lc.end(); lcit++) {
insert( (*lcit).first, (*lcit).second);
}
CGAL_triangulation_postcondition( is_valid() );
}
template<class InputIterator>
Constrained_triangulation_plus_2(InputIterator first,
InputIterator last,
const Geom_traits& gt=Geom_traits() )
: Triangulation(gt)
{
while( first != last){
insert((*first).first, (*first).second);
++first;
}
CGAL_triangulation_postcondition( is_valid() );
}
// INSERTION
Vertex_handle insert(Point a);
Vertex_handle insert(const Point& p,
Locate_type lt,
Face_handle loc, int li );
void insert(Point a, Point b);
void insert(Vertex_handle va, Vertex_handle vb);
Vertex_handle push_back(const Point& a);
void push_back(const Constraint& c);
//SUPPRESSION
// to be done next
protected:
void update_new_edges(Point a, Point b,
Vertex_handle vi,
Vertex_handle vh,
List_edges& new_edges);
Vertex_handle intersect(Face_handle f, int i,
Vertex_handle vaa,
Vertex_handle vbb);
Vertex_handle intersect(Face_handle f, int i,
Vertex_handle vaa,
Vertex_handle vbb,
Tag_false);
Vertex_handle intersect(Face_handle f, int i,
Vertex_handle vaa,
Vertex_handle vbb,
Tag_true);
Vertex_handle insert_part(Vertex_handle va,
Vertex_handle vb,
Vertex_handle vaa);
Vertex_handle find_intersected_faces(Vertex_handle va,
Vertex_handle vb,
Vertex_handle vaa,
List_faces & intersected_faces,
List_edges & list_ab,
List_edges & list_ba,
List_edges & new_edges);
//to debug
public:
void print_hierarchy() { return hierarchy.print();}
};
template <class Tr, class I_tag >
inline
Constrained_triangulation_plus_2<Tr,I_tag>::Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
push_back(const Point &p)
{
return insert(p);
}
template <class Tr, class I_tag >
inline
void
Constrained_triangulation_plus_2<Tr,I_tag>::
push_back(const Constraint &c)
{
insert(c.first, c.second);
}
template < class Tr, class I_tag >
inline
Constrained_triangulation_plus_2<Tr,I_tag>::Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
insert(Point a)
{
Locate_type lt;
int li;
Face_handle loc = locate(a, lt, li);
return insert(a,lt,loc,li);
}
template < class Gt, class Tds >
Constrained_triangulation_plus_2<Gt,Tds>::Vertex_handle
Constrained_triangulation_plus_2<Gt,Tds>::
insert(const Point& a, Locate_type lt, Face_handle loc, int li)
{
Vertex_handle v1, v2;
bool insert_in_constrained_edge = false;
if ( lt == EDGE && loc->is_constrained(li) ){
insert_in_constrained_edge = true;
v1=loc->vertex(ccw(li)); //endpoint of the constraint
v2=loc->vertex(cw(li)); // endpoint of the constraint
}
Vertex_handle va = Triangulation::insert(a,lt,loc,li);
// update the hierarchy
if (insert_in_constrained_edge) {
hierarchy.split_constraint(v1,v2,va);
}
return va;
}
template <class Tr, class I_tag >
inline void
Constrained_triangulation_plus_2<Tr,I_tag>::
insert(Point a, Point b)
// insert endpoints first
{
Vertex_handle va= insert(a);
Vertex_handle vb= insert(b);
insert(va, vb);
}
template <class Tr, class I_tag >
inline void
Constrained_triangulation_plus_2<Tr,I_tag>::
insert(Vertex_handle va, Vertex_handle vb)
{
hierarchy.insert_constraint(va, vb);
Vertex_handle vaa = va;
while (vaa != vb) {
Vertex_handle vbb = insert_part(va,vb,vaa);
if (vbb != vb) hierarchy.split_constraint(vaa,vb,vbb);
vaa=vbb;
}
return;
}
template <class Tr, class I_tag >
inline
Constrained_triangulation_plus_2<Tr,I_tag>::Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
insert_part(Vertex_handle va,
Vertex_handle vb,
Vertex_handle vaa)
{
Vertex_handle vbb;
Face_handle fr;
int i;
if(includes_edge(vaa,vb,vbb,fr,i)) {
mark_constraint(fr,i);
return vbb;
}
List_faces intersected_faces;
List_edges conflict_boundary_ab, conflict_boundary_ba;
List_edges new_edges;
vbb = find_intersected_faces( va, vb, vaa,
intersected_faces,
conflict_boundary_ab,
conflict_boundary_ba,
new_edges);
triangulate_hole(intersected_faces,
conflict_boundary_ab,
conflict_boundary_ba,
new_edges,
vbb);
return vbb;
}
template <class Tr, class I_tag >
Constrained_triangulation_plus_2<Tr,I_tag>::Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
find_intersected_faces(Vertex_handle va,
Vertex_handle vb,
Vertex_handle vaa,
List_faces & intersected_faces,
List_edges & list_ab,
List_edges & list_ba,
List_edges & new_edges)
// finds all triangles intersected the current part of constraint va
// vb
// vaa is the vertex at the begin of the current part
// the procedure returns the vertex vbb at the end of the current
// part
// The current part ends either when the current segment
// encounters a vertx of the triangulation or intersect
// a constrained edge or the vertex vb is reached.
// At the end of the procedure
// List_faces return the list of intersectef faces by the current
// part
// list_ab and list_ba represents the boundary of the union
// of the intersected faces oriented cw
// list_ab consists of the edges from vaa to vbb (i.e. on the left of a->b)
// list_ba " " from vbb to vaa (i.e. on the right of a->b)
// an element of the lists (an edge e) is represented as the edge of
// the triangle incident to e that is not intersected by ab
// new edges contains the edges created by the intersection
// which are not constrained (and also some of the constrained ones)
{
Point a=va->point(), b=vb->point();
Line_face_circulator current_face=line_walk(vaa->point(),b, vaa->face());
int ind=current_face->index(vaa);
Vertex_handle vh, vhh;
Face_handle fh;
int ih;
if(current_face->is_constrained(ind)) {
// to deal with the case where the first crossed edge
// is constrained
vh = current_face->mirror_vertex(ind);
Vertex_handle vi=intersect(current_face, ind, vaa, vb);
// to set the edge vaa vi as constrained
assert(is_edge(vi,vaa,fh,ih));
fh->set_constraint(ih,true);
(fh->neighbor(ih))->set_constraint(fh->mirror_index(ih),true);
// new_vertices.push_back(vi);
//no need to insert (vi,vaa) in new_edges because it is constrained....
update_new_edges(a,b,vi,vh,new_edges);
return vi;
}
Vertex_handle vbb=vb;
Face_handle lf= current_face->neighbor(ccw(ind));
Face_handle rf= current_face->neighbor(cw(ind));
Orientation orient;
Face_handle previous_face;
Vertex_handle current_vertex;
list_ab.push_back(Edge(lf, lf->index(current_face)));
list_ba.push_front(Edge(rf, rf->index(current_face)));
intersected_faces.push_front(current_face);
// init
previous_face=current_face;
++current_face;
ind=current_face->index(previous_face);
current_vertex=current_face->vertex(ind);
// loop over triangles intersected by ab
while (current_vertex != vbb) {
orient = orientation(a,b,current_vertex->point());
int i1, i2;
switch (orient) {
case COLLINEAR :
vbb=current_vertex; // new endpoint of the constraint
break;
case LEFTTURN :
case RIGHTTURN :
if (orient == LEFTTURN) {
i1 = ccw(ind) ; //index of second intersected edge of current_face
i2 = cw(ind); //index of non intersected edge of current_face
}
else {
i1 = cw(ind) ; //index of second intersected edge of current_face
i2 = ccw(ind); //index of non intersected edge of current_face
}
if(current_face->is_constrained(i1)) {
vhh = current_face->vertex(i1);
vh = current_face->mirror_vertex(i1);
Vertex_handle vi=intersect(current_face, i1, vaa,vb);
//new_vertices.push_back(vi);
update_new_edges(a,b,vi,vh,new_edges);
update_new_edges(a,b,vi,vhh,new_edges);
current_face=line_walk(vi->point(),a,vi->face());
// a essayer
// current_face=Line_face_circulator(vi,this,a);
current_vertex = vi;
ind = current_face->index(current_vertex);
vbb = vi; // new endpoint of the constraint
}
else {
lf= current_face->neighbor(i2);
intersected_faces.push_front(current_face);
if (orient == LEFTTURN)
list_ab.push_back(Edge(lf, lf->index(current_face)));
else // orient == RIGHTTURN
list_ba.push_front(Edge(lf, lf->index(current_face)));
previous_face=current_face;
++current_face;
ind=current_face->index(previous_face);
current_vertex=current_face->vertex(ind);
}
break;
}
}
// last triangle (having vbb as a vertex)
intersected_faces.push_front(current_face);
lf= current_face->neighbor(cw(ind));
list_ab.push_back(Edge(lf, lf->index(current_face)));
rf= current_face->neighbor(ccw(ind));
list_ba.push_front(Edge(rf, rf->index(current_face)));
return vbb;
}
template <class Tr, class I_tag >
void
Constrained_triangulation_plus_2<Tr,I_tag>::
update_new_edges(Point a, Point b,
Vertex_handle vi,
Vertex_handle vh,
List_edges& new_edges)
// add edge vi vh = (fh,ih) in the list of new_edges
// taking care that the face fh is not intersected by ab
// and thus will not be destroyed
{
Face_handle fh;
int ih;
assert( is_edge(vi,vh,fh,ih));
if ( orientation(a,b,vh->point()) ==
orientation(a,b,fh->vertex(ih)->point())) {
// face fh is not traversed by ab and will not be deleted
new_edges.push_back(Edge(fh,ih));
}
else {
new_edges.push_back(Edge(fh->neighbor(ih),fh->mirror_index(ih)));
}
}
template <class Tr, class I_tag >
Constrained_triangulation_plus_2<Tr,I_tag>:: Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
intersect(Face_handle f, int i,
Vertex_handle vaa,
Vertex_handle vbb)
{
return intersect(f, i, vaa, vbb, Intersection_tag());
}
template <class Tr, class I_tag >
Constrained_triangulation_plus_2<Tr,I_tag>:: Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
intersect(Face_handle f, int i,
Vertex_handle vaa,
Vertex_handle vbb,
Tag_false)
{
std::cerr << " sorry, this triangulation does not deal "
<< std::endl
<< " intersecting constraints" << std::endl;
assert(false);
return Vertex_handle();
}
template <class Tr, class I_tag >
Constrained_triangulation_plus_2<Tr,I_tag>:: Vertex_handle
Constrained_triangulation_plus_2<Tr,I_tag>::
intersect(Face_handle f, int i,
Vertex_handle vaa,
Vertex_handle vbb,
Tag_true)
// compute the intersection of the constraint edge (f,i)
// with the subconstraint (vaa,vbb) being inserted
// insert the intersection point
// split constraint edge (f,i) in hierarchy
// and return the Vertex_handle of the new Vertex
{
Vertex_handle vc, vd, va, vb;
Vertex_handle vcc, vdd;
vcc = f->vertex(cw(i));
vdd = f->vertex(ccw(i));
assert(hierarchy.enclosing_constraint(vcc,vdd,vc,vd));
assert(hierarchy.enclosing_constraint(vaa,vbb,va,vb));
Point pi; //creator for point is required here
Object result;
result = intersection(Segment(vc->point(),vd->point()),
Segment(va->point(),vb->point()));
assert(assign(pi, result));
Vertex_handle vi = special_insert_in_edge(pi,f,i);
hierarchy.split_constraint(vcc,vdd,vi);
return vi;
}
template <class Tr, class I_tag >
std::ostream &
operator<<(std::ostream& os,
const Constrained_triangulation_plus_2<Tr,I_tag> &ct)
{
ct.file_output(os);
return os ;
}
CGAL_END_NAMESPACE
#endif //CGAL_CONSTRAINED_TRIANGULATION_PLUS_2_H