CGAL users discussion list

[hardik kabaria <>]

Hi everyone, 

I am having some trouble with AABB tree and finding closest point projection to a given query point.

cgal                           @4.5            gis/cgal

gcc version 4.8.2

I have triangular mesh file ,

and the corresponding .cpp file is pasted  here

#include <iostream>

#include <CGAL/Simple_cartesian.h>

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>

#include <CGAL/AABB_tree.h>

#include <CGAL/AABB_traits.h>

#include <CGAL/Polyhedron_3.h>

#include <CGAL/AABB_polyhedron_triangle_primitive.h>

#include <CGAL/Polyhedron_3.h>

#include <CGAL/IO/Polyhedron_iostream.h>

#include <iostream>

#include <fstream>

// typedef CGAL::Simple_cartesian<double> K;

typedef CGAL::Exact_predicates_inexact_constructions_kernel K;

typedef K::FT FT;

typedef K::Point_3 Point;

typedef K::Segment_3 Segment;

typedef CGAL::Polyhedron_3<K> Polyhedron;

typedef CGAL::AABB_polyhedron_triangle_primitive<K,Polyhedron> Primitive;

typedef CGAL::AABB_traits<K, Primitive> Traits;

typedef CGAL::AABB_tree<Traits> Tree;

typedef Tree::Object_and_primitive_id Object_and_primitive_id;

typedef Tree::Point_and_primitive_id Point_and_primitive_id;

int main()

{

    Point p(1.0, 0.0, 0.0);

    Point q(0.0, 1.0, 0.0);

    Point r(0.0, 0.0, 1.0);

    Point s(0.0, 0.0, 0.0);

    Polyhedron polyhedron;

    std::ifstream input("./poisson_rec.off");

    input>>polyhedron;

    // polyhedron.make_tetrahedron(p, q, r, s);

    // constructs AABB tree and computes internal KD-tree 

    // data structure to accelerate distance queries

    Tree tree(polyhedron.facets_begin(),polyhedron.facets_end());

    tree.accelerate_distance_queries();

    // query point

    Point query(0.5, 0.5, 0.5);

    // computes squared distance from query

    FT sqd = tree.squared_distance(query);

    std::cout << "squared distance: " << sqd << std::endl;

    // computes closest point

    Point closest = tree.closest_point(query);

    std::cout << "closest point: " << closest << std::endl;

    // computes closest point and primitive id

    Point_and_primitive_id pp = tree.closest_point_and_primitive(query);

    Point cpt = tree.closest_point(Point(0.5,0.5,0.5));

    std::cout<<cpt<<std::endl;

    Point closest_point = pp.first;

    Polyhedron::Face_handle f = pp.second; // closest primitive id

    std::cout << "closest point: " << closest_point << std::endl;

    std::cout << "closest triangle: ( "

              << f->halfedge()->vertex()->point() << " , " 

              << f->halfedge()->next()->vertex()->point() << " , "

              << f->halfedge()->next()->next()->vertex()->point()

              << " )" << std::endl;

    return EXIT_SUCCESS;

} 

It gives me segmentation fault. The .cpp is exactly that of AABB_polyhedron_facet_distance_example.cpp

Can someone shade light on what am I doing wrong ?

Thanks!

--

Hardik Kabaria
Ph.D. Candidate
Department of Mechanical Engineering
Stanford University