CGAL 4.12.1 - 3D Fast Intersection and Distance Computation (AABB Tree)
AABB_tree/AABB_halfedge_graph_edge_example.cpp
// Author(s) : Pierre Alliez
#include <iostream>
#include <CGAL/Simple_cartesian.h>
#include <CGAL/AABB_tree.h>
#include <CGAL/AABB_traits.h>
#include <CGAL/Polyhedron_3.h>
#include <CGAL/AABB_halfedge_graph_segment_primitive.h>
typedef K::FT FT;
typedef K::Point_3 Point;
typedef K::Triangle_3 Triangle;
typedef CGAL::Polyhedron_3<K> Polyhedron;
template <class Kernel, class HalfedgeGraph>
void run(const HalfedgeGraph& graph){
typename Kernel::Point_3 p(1.0, 0.0, 0.0);
typename Kernel::Point_3 q(0.0, 1.0, 0.0);
typename Kernel::Point_3 r(0.0, 0.0, 1.0);
// constructs the AABB tree and the internal search tree for
// efficient distance queries.
Tree tree( CGAL::edges(graph).first,
CGAL::edges(graph).second, graph);
tree.accelerate_distance_queries();
// counts #intersections with a triangle query
Triangle triangle_query(p,q,r);
std::cout << tree.number_of_intersected_primitives(triangle_query)
<< " intersections(s) with triangle" << std::endl;
assert( tree.number_of_intersected_primitives(triangle_query )== 6);
// computes the closest point from a query point
typename Kernel::Point_3 point_query(2.0, 2.0, 2.0);
typename Kernel::Point_3 closest = tree.closest_point(point_query);
std::cerr << "closest point is: " << closest << std::endl;
}
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;
polyhedron.make_tetrahedron(p, q, r, s);
run<K>(polyhedron);
return EXIT_SUCCESS;
}