// Copyright (c) 2001,2009,2014 Tel-Aviv University (Israel), Max-Planck-Institute Saarbruecken (Germany). // All rights reserved. // // This file is part of CGAL (www.cgal.org). // // $URL: https://github.com/CGAL/cgal/blob/v5.1/Snap_rounding_2/include/CGAL/Snap_rounding_traits_2.h $ // $Id: Snap_rounding_traits_2.h 254d60f 2019-10-19T15:23:19+02:00 Sébastien Loriot // SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial // // // author(s) : Eli Packer , // Waqar Khan #ifndef CGAL_SNAP_ROUNDING_2_TRAITS_H #define CGAL_SNAP_ROUNDING_2_TRAITS_H #include #include #include #include #include namespace CGAL { template class Snap_rounding_traits_2 : public CGAL::Arr_segment_traits_2 { public: // otherwise Segment_data cannot access the types typedef typename Base_kernel::FT NT; typedef typename Base_kernel::FT FT; typedef typename Base_kernel::Point_2 Point_2; typedef typename Base_kernel::Segment_2 Segment_2; typedef typename Base_kernel::Iso_rectangle_2 Iso_rectangle_2; typedef typename Base_kernel::Vector_2 Vector_2; typedef typename Base_kernel::Line_2 Line_2; typedef typename Base_kernel::Aff_transformation_2 Aff_transformation_2; typedef typename Base_kernel::Direction_2 Direction_2; typedef typename Base_kernel::Construct_vertex_2 Construct_vertex_2 ; typedef typename Base_kernel::Construct_segment_2 Construct_segment_2 ; typedef typename Base_kernel::Construct_iso_rectangle_2 Construct_iso_rectangle_2; typedef typename Base_kernel::Compare_y_2 Compare_y_2; typedef typename Base_kernel::Construct_min_vertex_2 Construct_min_vertex_2; typedef typename Base_kernel::Construct_max_vertex_2 Construct_max_vertex_2; typedef typename Base_kernel::Cartesian_const_iterator_2 Cartesian_const_iterator_2; typedef typename Base_kernel::Construct_cartesian_const_iterator_2 Construct_cartesian_const_iterator_2; typedef CGAL::Arr_segment_traits_2 Base_traits; typedef typename Base_traits::Compare_x_2 Compare_x_2; typedef CGAL::To_double To_double; public: /*! Functor */ class Snap_2 { public: void operator()(const Point_2& p, NT pixel_size, NT &x, NT &y) { NT x_tmp = p.x() / pixel_size; NT y_tmp = p.y() / pixel_size; NT x_floor = std::floor(CGAL::to_double(x_tmp)); NT y_floor = std::floor(CGAL::to_double(y_tmp)); // fix the usage of to_double and floor: // there is no guarantee that the double approximation of *_tmp // has the same integer part as the NT version. The while loops // is a simple way to ensure that *_tmp are the true floor. while(x_floor>x_tmp) x_floor-=NT(1); while(y_floor>y_tmp) y_floor-=NT(1); while(x_floor+1<=x_tmp) x_floor+=NT(1); while(y_floor+1<=y_tmp) y_floor+=NT(1); CGAL_assertion(x_floor<=x_tmp); CGAL_assertion(y_floor<=y_tmp); CGAL_assertion(x_floor+1>x_tmp); CGAL_assertion(y_floor+1>y_tmp); x = x_floor * pixel_size + pixel_size / NT(2.0); y = y_floor * pixel_size + pixel_size / NT(2.0); } }; Snap_2 snap_2_object() const { return Snap_2(); } /*! Functor */ class Integer_grid_point_2 { public: Point_2 operator()(const Point_2& p, NT pixel_size) { NT x = (p.x() - pixel_size / NT(2.0)) / pixel_size; NT y = (p.y() - pixel_size / NT(2.0)) / pixel_size; Point_2 out_p(x,y); return(out_p); } }; /*! */ Integer_grid_point_2 integer_grid_point_2_object() const { return Integer_grid_point_2(); } /*! Functor */ class Minkowski_sum_with_pixel_2 { private: typedef Snap_rounding_traits_2 Traits; typedef std::list Point_list; const Traits * m_gt; Minkowski_sum_with_pixel_2(const Traits * gt) : m_gt(gt) {} public: void operator()(Point_list & points_list, const Segment_2& s, NT unit_square) { Construct_vertex_2 construct_ver = m_gt->construct_vertex_2_object(); Compare_y_2 compare_y = m_gt->compare_y_2_object(); Compare_x_2 compare_x = m_gt->compare_x_2_object(); Point_2 src = construct_ver(s, 0); Point_2 trg = construct_ver(s, 1); Comparison_result cx = compare_x(src, trg); Comparison_result cy = compare_y(src, trg); NT x1 = src.x(); NT y1 = src.y(); NT x2 = trg.x(); NT y2 = trg.y(); Point_2 ms1, ms2, ms3, ms4, ms5, ms6;// minkowski sum points if (cx == SMALLER) { if (cy == SMALLER) { // we use unit_square instead of unit_square / 2 in order to // find tangency points which are not supported by kd-tree ms1 = Point_2(x1 - unit_square, y1 - unit_square); ms2 = Point_2(x1 - unit_square, y1 + unit_square); ms3 = Point_2(x1 + unit_square, y1 - unit_square); ms4 = Point_2(x2 + unit_square, y2 - unit_square); ms5 = Point_2(x2 + unit_square, y2 + unit_square); ms6 = Point_2(x2 - unit_square, y2 + unit_square); } else { ms1 = Point_2(x1 - unit_square, y1 - unit_square); ms2 = Point_2(x1 - unit_square, y1 + unit_square); ms3 = Point_2(x1 + unit_square, y1 + unit_square); ms4 = Point_2(x2 + unit_square, y2 - unit_square); ms5 = Point_2(x2 + unit_square, y2 + unit_square); ms6 = Point_2(x2 - unit_square, y2 - unit_square); } } else { if(cy == SMALLER) { ms1 = Point_2(x1 + unit_square, y1 - unit_square); ms2 = Point_2(x1 + unit_square, y1 + unit_square); ms3 = Point_2(x1 - unit_square, y1 - unit_square); ms4 = Point_2(x2 + unit_square, y2 + unit_square); ms5 = Point_2(x2 - unit_square, y2 + unit_square); ms6 = Point_2(x2 - unit_square, y2 - unit_square); } else { ms1 = Point_2(x1 + unit_square, y1 - unit_square); ms2 = Point_2(x1 + unit_square, y1 + unit_square); ms3 = Point_2(x1 - unit_square, y1 + unit_square); ms4 = Point_2(x2 + unit_square, y2 - unit_square); ms5 = Point_2(x2 - unit_square, y2 - unit_square); ms6 = Point_2(x2 - unit_square, y2 + unit_square); } } points_list.push_back(ms1); points_list.push_back(ms2); points_list.push_back(ms3); points_list.push_back(ms4); points_list.push_back(ms5); points_list.push_back(ms6); } friend class Snap_rounding_traits_2; }; /*! */ Minkowski_sum_with_pixel_2 minkowski_sum_with_pixel_2_object() const { return Minkowski_sum_with_pixel_2(this); } Construct_segment_2 construct_segment_2_object() const { Base_kernel k; return k.construct_segment_2_object(); } Construct_vertex_2 construct_vertex_2_object() const { Base_kernel k; return k.construct_vertex_2_object(); } Compare_y_2 compare_y_2_object() const { Base_kernel k; return k.compare_y_2_object(); } Construct_iso_rectangle_2 construct_iso_rectangle_2_object() const { Base_kernel k; return k.construct_iso_rectangle_2_object(); } }; } //namespace CGAL #endif // CGAL_ISR_2_TRAITS_H