Sébastien Loriot
4b603f40ba
I introduce a dedicated intersection traits and all CK2 member functions use this traits instead of the general one. That way, the return type is always correct. The same fix will be done for CK3
52 lines
1.9 KiB
C++
52 lines
1.9 KiB
C++
#include <CGAL/Exact_circular_kernel_2.h>
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#include <CGAL/point_generators_2.h>
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typedef CGAL::Exact_circular_kernel_2 Circular_k;
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typedef CGAL::Point_2<Circular_k> Point_2;
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typedef CGAL::Circle_2<Circular_k> Circle_2;
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typedef CGAL::Circular_arc_2<Circular_k> Circular_arc_2;
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template <typename T>
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double prob_2() {
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CGAL::Random_points_in_square_2<Point_2> g(1.0);
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double prob = 0.0;
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for (int i = 0; i < 10000; i++) {
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Point_2 p1, p2, p3, p4, p5, p6;
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p1 = *g++; p2 = *g++; p3 = *g++;
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p4 = *g++; p5 = *g++; p6 = *g++;
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// the pi's are points inherited from the Cartesian kernel Point_2, so,
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// the orientation predicate can be called on them
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if(CGAL::orientation(p1, p2, p3) != CGAL::COUNTERCLOCKWISE) std::swap(p1, p3);
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T o1 = T(p1, p2, p3);
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if(CGAL::orientation(p4, p5, p6) != CGAL::COUNTERCLOCKWISE) std::swap(p4, p6);
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T o2 = T(p4, p5, p6);
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typedef typename CGAL::CK2_Intersection_traits<Circular_k, T, T>::type
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Intersection_result;
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std::vector<Intersection_result> res;
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CGAL::intersection(o1, o2, std::back_inserter(res));
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prob += (res.size() != 0) ? 1.0 : 0.0;
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}
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return prob/10000.0;
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}
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int main()
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{
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std::cout << "What is the probability that two arcs formed by" << std::endl;
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std::cout << "three random counterclockwise-oriented points on" << std::endl;
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std::cout << "an unit square intersect? (wait a second please)" << std::endl;
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std::cout << "The probability is: " << prob_2<Circular_arc_2>() <<
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std::endl << std::endl;
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std::cout << "And what about the probability that two circles formed by"
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<< std::endl;
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std::cout << "three random counterclockwise-oriented points on" << std::endl;
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std::cout << "an unit square intersect? (wait a second please)" << std::endl;
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std::cout << "The probability is: " << prob_2<Circle_2>() << std::endl;
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return 0;
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}
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