/**
* Finds the exit point of upslope_path on the facet left of h.
*
* upslope_path must intersect the boundary of the facet in 2 points or a
* segment. One of these points must be start_point. If the intersection is a
* segment, returns the endpoint that is not start_point. Otherwise returns the
* other intersection point. Updates h so it is the halfedge where the
* intersection is found.
*/
Point_2 find_exit(Halfedge_handle& h, const Ray_2& upslope_path,
const Point_2& start_point)
{
Point_2 exit;
Plane_3 plane = h->facet()->plane();
typedef Facet::Halfedge_around_facet_circulator Circulator;
Circulator current = h->facet()->facet_begin();
Circulator end = h->facet()->facet_begin();
do {
Point_2 source = plane.to_2d(current->vertex()->point());
Point_2 target = plane.to_2d(current->opposite()->vertex()->point());
Segment_2 seg = Segment_2(source, target);
// Example pulled from http://tinyurl.com/intersect-doc
CGAL::Object intersect = CGAL::intersection(upslope_path, seg);
// Return for a point intersection
if (const CGAL::Point_2<Kernel> *ipoint =
CGAL::object_cast<CGAL::Point_2<Kernel> >(&intersect)) {
if (*ipoint != start_point) {
h = current;
return *ipoint;
}
}
// Return the opposite point of the segment for a segment intersection.
else if (const CGAL::Segment_2<Kernel> *iseg =
CGAL::object_cast<CGAL::Segment_2<Kernel> >(&intersect)) {
h = current;
if (iseg->source() == start_point)
return iseg->target();
return iseg->source();
}
} while (++current != end);
cout << "Failed to find an intersection point." << endl;
cout << "Start: " << start_point << endl;
cout << "Upslope path: " << upslope_path << endl;
print_facet(*h->facet());
std::abort();
return exit;
}
typename Poly::Halfedge_handle make_cube_3( Poly& P) {
// appends a cube of size [0,1]^3 to the polyhedron P.
CGAL_precondition( P.is_valid());
typedef typename Poly::Point_3 Point;
typedef typename Poly::Plane_3 Plane;
typedef typename Poly::Halfedge_handle Halfedge_handle;
Halfedge_handle h = P.make_tetrahedron( Point( 1, 0, 0),
Point( 0, 0, 1),
Point( 0, 0, 0),
Point( 0, 1, 0));
Halfedge_handle g = h->next()->opposite()->next();
P.split_edge( h->next());
P.split_edge( g->next());
P.split_edge( g);
h->next()->vertex()->point() = Point( 1, 0, 1);
g->next()->vertex()->point() = Point( 0, 1, 1);
g->opposite()->vertex()->point() = Point( 1, 1, 0);
Halfedge_handle f = P.split_facet( g->next(), g->next()->next()->next());
Halfedge_handle e = P.split_edge( f);
e->vertex()->point() = Point( 1, 1, 1);
P.split_facet( e, f->next()->next());
CGAL_postcondition( P.is_valid());
g = h;
g->facet()->plane() = Plane( g->vertex()->point(),
g->next()->vertex()->point(),
g->next()->next()->vertex()->point());
g = h->opposite();
g->facet()->plane() = Plane( g->vertex()->point(),
g->next()->vertex()->point(),
g->next()->next()->vertex()->point());
g = h->next()->opposite();
g->facet()->plane() = Plane( g->vertex()->point(),
g->next()->vertex()->point(),
g->next()->next()->vertex()->point());
g = h->next()->next()->opposite();
g->facet()->plane() = Plane( g->vertex()->point(),
g->next()->vertex()->point(),
g->next()->next()->vertex()->point());
g = h->next()->next()->next()->opposite();
g->facet()->plane() = Plane( g->vertex()->point(),
g->next()->vertex()->point(),
g->next()->next()->vertex()->point());
g = g->next()->next()->opposite();
g->facet()->plane() = Plane( g->vertex()->point(),
g->next()->vertex()->point(),
g->next()->next()->vertex()->point());
return h;
}
void Boolean_Operations_Component::SubdiviserPolyedre(PolyhedronPtr pMesh)
{
//Each facet must be triangular
if(!pMesh->is_pure_triangle())
{
pMesh->triangulate();
return;
}
Facet_iterator pFacet;
Vector Vcenter;
//Initialization of the tags
for (pFacet = pMesh->facets_begin(); pFacet != pMesh->facets_end(); pFacet++)
{
Halfedge_around_facet_circulator pHEcirc = pFacet->facet_begin();
pFacet->Issub = false;
pHEcirc->Isnew = false;
pHEcirc->vertex()->Isnew = false;
pHEcirc++;
pHEcirc->Isnew = false;
pHEcirc->vertex()->Isnew = false;
pHEcirc++;
pHEcirc->Isnew = false;
pHEcirc->vertex()->Isnew = false;
}
//For each facet of the polyhedron
for (pFacet = pMesh->facets_begin(); pFacet != pMesh->facets_end(); pFacet++)
{
//We subdivide the facet if it is not already done
if(!(pFacet->Issub))
{
Halfedge_handle pHE = pFacet->facet_begin();
for(unsigned int i = 0;i!=5;i++)
{
if(!pHE->Isnew)
{
//each edge is splited in its center
Vcenter = Vector(0.0, 0.0, 0.0);
Vcenter = ( (pHE->vertex()->point() - CGAL::ORIGIN) + (pHE->opposite()->vertex()->point() - CGAL::ORIGIN) ) / 2;
pHE = pMesh->split_edge(pHE);
pHE->vertex()->point() = CGAL::ORIGIN + Vcenter;
//update of the tags (the new vertex and the four new halfedges
pHE->vertex()->Isnew = true;
pHE->Isnew = true;
pHE->opposite()->Isnew = true;
pHE->next()->Isnew = true;
pHE->next()->opposite()->Isnew = true;
}
pHE = pHE->next();
}
//Three new edges are build between the three new vertices, and the tags of the facets are updated
if(!pHE->vertex()->Isnew) pHE = pHE->next();
pHE = pMesh->split_facet(pHE, pHE->next()->next());
pHE->opposite()->facet()->Issub = true;
pHE = pMesh->split_facet(pHE, pHE->next()->next());
pHE->opposite()->facet()->Issub = true;
pHE = pMesh->split_facet(pHE, pHE->next()->next());
pHE->opposite()->facet()->Issub = true;
pHE->facet()->Issub = true;
}
}
}
void PolyDataGenerator::ClosePolygon(void){
Halfedge_iterator j;
Halfedge_iterator k;
Halfedge_iterator l;
Halfedge_iterator m;
Halfedge_handle newedge;
cout << "The polyhedron has " << ClippedCGALSurface->size_of_facets() << " facets "
<< ClippedCGALSurface->size_of_halfedges() << " halfedges " <<
ClippedCGALSurface->size_of_border_halfedges() << " border halfedges "
<< ClippedCGALSurface->size_of_vertices() << " vertices " << endl;
int ncompremoved = ClippedCGALSurface->keep_largest_connected_components(1);
cout << "Removing " << ncompremoved << " non connected components" << endl;
cout << "The polyhedron has " << ClippedCGALSurface->size_of_facets() << " facets "
<< ClippedCGALSurface->size_of_halfedges() << " halfedges " <<
ClippedCGALSurface->size_of_border_halfedges() << " border halfedges "
<< ClippedCGALSurface->size_of_vertices() << " vertices " << endl;
while(!this->ClippedCGALSurface->is_closed()){
for (j = ClippedCGALSurface->border_halfedges_begin(); j != ClippedCGALSurface->halfedges_end(); ++j){
// We itterate over all border half edges. Half of them are opposite border edegs and thus not
// real borders so test this first.
// it.next() it the next border edge along the hole. This might not be the same as ++it
k = j->next();
l = k->next();
m = l->next();
if (j->is_border() && l->is_border() && k->is_border()){
//First find size of hole and make sure that this is simple. i.e.
//No two different halfedges points to the same vertex.
//If this is the case we delete one of them and start over.
Halfedge_iterator tempit = k;
Halfedge_iterator tempit2;
int sizehole = 1;
bool Simplehole = true;
while(tempit != j){
for(tempit2 = j; tempit2 != tempit ; tempit2=tempit2->next() ){
if (tempit2->vertex() == tempit->vertex()){
Simplehole = false;
ClippedCGALSurface->erase_facet(tempit2->opposite());
break; //remove one facet and start over.
}
}
if(!Simplehole){
break; //ugly Break inermost while loop.
}
tempit = tempit->next();
++sizehole;
}
if (Simplehole){
//cout << "Hole has " << sizehole << endl;
if (j != m){ //more than 3 edges in hole. Have to subdivide
newedge = ClippedCGALSurface->add_facet_to_border(j,l);
//cout << "Filling " << j->vertex()->point() << " , " << k->vertex()->point() << " to " << newedge->vertex()->point() << endl;
}
else{
//cout << "Closing " << j->vertex()->point() << " to " << k->vertex()->point() << endl;
newedge = ClippedCGALSurface->fill_hole(j);
}
// now find the iolet type from neighbors.
tempit = newedge;
bool start = true;
std::vector<size_t> neighborIds;
while(tempit != newedge || start){
start = false;
if (!tempit->opposite()->is_border()){
neighborIds.push_back(tempit->opposite()->facet()->id());
}
tempit = tempit->next();
}
std::vector<size_t>::iterator max = std::max_element(neighborIds.begin(), neighborIds.end());
std::vector<size_t>::iterator min = std::min_element(neighborIds.begin(), neighborIds.end());
if (*max != *min){ // if max is min they are all the same.
throw GenerationErrorMessage("Could not determin IOlet id of inserted facet.");
}
else{
newedge->facet()->id() = *max;
}
break; //we have to normalize the border and restart the forloop since
// filling with add_facet_to_border invalidated the order of border/non border edges.
}
else {
//cout << "Could not fill since hole is not simple, deleted connected facet instead" << endl;
break;
}
}
}
ClippedCGALSurface->normalize_border();
}
}