\( \newcommand{\E}{\mathrm{E}} \) \( \newcommand{\A}{\mathrm{A}} \) \( \newcommand{\R}{\mathrm{R}} \) \( \newcommand{\N}{\mathrm{N}} \) \( \newcommand{\Q}{\mathrm{Q}} \) \( \newcommand{\Z}{\mathrm{Z}} \) \( \def\ccSum #1#2#3{ \sum_{#1}^{#2}{#3} } \def\ccProd #1#2#3{ \sum_{#1}^{#2}{#3} }\)
CGAL 4.12 - 3D Fast Intersection and Distance Computation (AABB Tree)
AABB_tree/AABB_face_graph_triangle_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_face_graph_triangle_primitive.h>
typedef K::FT FT;
typedef K::Point_3 Point;
typedef K::Segment_3 Segment;
typedef CGAL::Polyhedron_3<K> Polyhedron;
template <class Kernel, class FaceGraph>
void run(const FaceGraph& graph){
typename Kernel::Point_3 p(0.2, 0.2, 0.2);
typename Kernel::Point_3 q(1.0, 1.0, 1.0);
// constructs the AABB tree and the internal search tree for
// efficient distance queries.
Tree tree( faces(graph).first, faces(graph).second, graph);
tree.accelerate_distance_queries();
// counts #intersections with a triangle query
Segment segment_query(p,q);
std::cout << tree.number_of_intersected_primitives(segment_query)
<< " intersections(s) with triangle" << std::endl;
assert( tree.number_of_intersected_primitives(segment_query)== 1 );
// 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;
}