examples/alphashapes/alphashapes2d.hpp
author Dmitriy Morozov <dmitriy@mrzv.org>
Tue, 05 Jun 2012 17:53:08 -0700
branchdev
changeset 258 bb5bc5eff779
parent 242 a06b4b515476
child 272 29306411272b
permissions -rw-r--r--
Added viewer.show_complex_2D + center points in the persistence diagram

#include <utilities/log.h>
#include <boost/foreach.hpp>

AlphaSimplex2D::	    
AlphaSimplex2D(const Delaunay2D::Vertex& v): alpha_(0), attached_(false)
{
	for (int i = 0; i < 3; ++i)
		if (v.face()->vertex(i) != Vertex_handle() && v.face()->vertex(i)->point() == v.point())
			Parent::add(v.face()->vertex(i));
}

AlphaSimplex2D::	    
AlphaSimplex2D(const Delaunay2D::Edge& e): attached_(false)
{
    Face_handle f = e.first;
	for (int i = 0; i < 3; ++i)
		if (i != e.second)
			Parent::add(f->vertex(i));
}

AlphaSimplex2D::	    
AlphaSimplex2D(const Delaunay2D::Edge& e, const SimplexSet& simplices, const Delaunay2D& Dt): attached_(false)
{
    Face_handle f = e.first;
	for (int i = 0; i < 3; ++i)
		if (i != e.second)
			Parent::add(f->vertex(i));

	VertexSet::const_iterator v = static_cast<const Parent*>(this)->vertices().begin();
	const Point& p1 = (*v++)->point();
	const Point& p2 = (*v)->point();
	
	Face_handle o = f->neighbor(e.second);
    if (o == Face_handle())
    {
        alpha_ = squared_radius(p1, p2);
        return;
    }
	int oi = o->index(f);

	attached_ = false;
	if (!Dt.is_infinite(f->vertex(e.second)) &&
        CGAL::side_of_bounded_circle(p1, p2, 
									 f->vertex(e.second)->point()) == CGAL::ON_BOUNDED_SIDE)
		attached_ = true;
	else if (!Dt.is_infinite(o->vertex(oi)) &&
             CGAL::side_of_bounded_circle(p1, p2,
										  o->vertex(oi)->point()) == CGAL::ON_BOUNDED_SIDE)
		attached_ = true;
	else
		alpha_ = squared_radius(p1, p2);

	if (attached_)
	{
		if (Dt.is_infinite(f))
			alpha_ = simplices.find(AlphaSimplex2D(*o))->alpha();
		else if (Dt.is_infinite(o))
			alpha_ = simplices.find(AlphaSimplex2D(*f))->alpha();
		else
			alpha_ = std::min(simplices.find(AlphaSimplex2D(*f))->alpha(), 
                              simplices.find(AlphaSimplex2D(*o))->alpha());
	}
}

AlphaSimplex2D::	    
AlphaSimplex2D(const Delaunay2D::Face& f): attached_(false)
{
	for (int i = 0; i < 3; ++i)
		Parent::add(f.vertex(i));
	VertexSet::const_iterator v = static_cast<const Parent*>(this)->vertices().begin();
	Point p1 = (*v++)->point();
	Point p2 = (*v++)->point();
	Point p3 = (*v)->point();
	alpha_ = CGAL::squared_radius(p1, p2, p3);
}


bool 
AlphaSimplex2D::AlphaOrder::
operator()(const AlphaSimplex2D& first, const AlphaSimplex2D& second) const
{
	if (first.alpha() == second.alpha())
		return (first.dimension() < second.dimension());
	else
		return (first.alpha() < second.alpha()); 
}

std::ostream& 
AlphaSimplex2D::
operator<<(std::ostream& out) const
{
	for (VertexSet::const_iterator cur = Parent::vertices().begin(); 
								   cur != Parent::vertices().end(); ++cur)
		out << **cur << ", ";
	out << "value = " << value();

	return out;
}

void fill_simplex_set(const Delaunay2D& Dt, AlphaSimplex2D::SimplexSet& simplices)
{
	for(Face_iterator cur = Dt.finite_faces_begin(); cur != Dt.finite_faces_end(); ++cur)
		simplices.insert(AlphaSimplex2D(*cur));
	rInfo("Faces inserted");
	for(Edge_iterator cur = Dt.finite_edges_begin(); cur != Dt.finite_edges_end(); ++cur)
		simplices.insert(AlphaSimplex2D(*cur, simplices, Dt));
	rInfo("Edges inserted");
	for(Vertex_iterator cur = Dt.finite_vertices_begin(); cur != Dt.finite_vertices_end(); ++cur)
		simplices.insert(AlphaSimplex2D(*cur));
	rInfo("Vertices inserted");
}

template<class Filtration>
void fill_complex(const Delaunay2D& Dt, Filtration& filtration)
{
	// Compute all simplices with their alpha values and attachment information
    // TODO: this can be optimized; the new Filtration can act as a SimplexSet
	AlphaSimplex2D::SimplexSet simplices;
    fill_simplex_set(Dt, simplices);
    BOOST_FOREACH(const AlphaSimplex2D& s, simplices)
        filtration.push_back(s);
}