// Copyright (c) 2008 GeometryFactory, Sophia-Antipolis (France). // All rights reserved. // // This file is part of CGAL (www.cgal.org). // You can redistribute it and/or modify it under the terms of the GNU // General Public License as published by the Free Software Foundation, // either version 3 of the License, or (at your option) any later version. // // Licensees holding a valid commercial license may use this file in // accordance with the commercial license agreement provided with the software. // // This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE // WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. // // $URL$ // $Id$ // // // Author(s) : Laurent RINEAU #ifndef CGAL_MESH_3_DIHEDRAL_ANGLE_3_H #define CGAL_MESH_3_DIHEDRAL_ANGLE_3_H #include #include #include namespace CGAL { namespace Mesh_3 { /** * Computes dihedral angle of planes (a,b,c) and (a,b,d) */ template typename K::FT dihedral_angle(const typename K::Point_3& a, const typename K::Point_3& b, const typename K::Point_3& c, const typename K::Point_3& d, K k = K()) { typename K::Construct_vector_3 vector = k.construct_vector_3_object(); typename K::Construct_cross_product_vector_3 cross_product = k.construct_cross_product_vector_3_object(); typename K::Compute_squared_distance_3 sq_distance = k.compute_squared_distance_3_object(); typename K::Compute_scalar_product_3 scalar_product = k.compute_scalar_product_3_object(); typedef typename K::Vector_3 Vector_3; typedef typename K::FT FT; const Vector_3 ab = vector(a,b); const Vector_3 ac = vector(a,c); const Vector_3 ad = vector(a,d); const Vector_3 abad = cross_product(ab,ad); const double x = CGAL::to_double(scalar_product(cross_product(ab,ac), abad)); const double l_ab = CGAL::sqrt(CGAL::to_double(sq_distance(a,b))); const double y = l_ab * CGAL::to_double(scalar_product(ac,abad)); return FT(std::atan2(y, x) * 180 / CGAL_PI ); } /** * Computes dihedral angle of planes (a,b,c) and (a,b,d) */ template typename Kernel_traits::Kernel::FT dihedral_angle(const Point_3& a, const Point_3& b, const Point_3& c, const Point_3& d) { return dihedral_angle(a, b, c, d, typename Kernel_traits::Kernel()); } } // end namespace Mesh_3 } // end namespace CGAL #endif // CGAL_MESH_3_DIHEDRAL_ANGLE_3_H