diff options
Diffstat (limited to 'boost/geometry/strategies/geographic/buffer_join_round.hpp')
-rw-r--r-- | boost/geometry/strategies/geographic/buffer_join_round.hpp | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/boost/geometry/strategies/geographic/buffer_join_round.hpp b/boost/geometry/strategies/geographic/buffer_join_round.hpp new file mode 100644 index 0000000000..4f891d0573 --- /dev/null +++ b/boost/geometry/strategies/geographic/buffer_join_round.hpp @@ -0,0 +1,123 @@ +// Boost.Geometry + +// Copyright (c) 2022 Barend Gehrels, Amsterdam, the Netherlands. +// Copyright (c) 2023 Adam Wulkiewicz, Lodz, Poland. + +// Use, modification and distribution is subject to the Boost Software License, +// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) + +#ifndef BOOST_GEOMETRY_STRATEGIES_GEOGRAPHIC_BUFFER_JOIN_ROUND_HPP +#define BOOST_GEOMETRY_STRATEGIES_GEOGRAPHIC_BUFFER_JOIN_ROUND_HPP + +#include <boost/range/value_type.hpp> + +#include <boost/geometry/core/radian_access.hpp> + +#include <boost/geometry/srs/spheroid.hpp> +#include <boost/geometry/strategies/buffer.hpp> +#include <boost/geometry/strategies/geographic/buffer_helper.hpp> +#include <boost/geometry/strategies/geographic/parameters.hpp> +#include <boost/geometry/util/math.hpp> +#include <boost/geometry/util/select_calculation_type.hpp> + + +namespace boost { namespace geometry +{ + +namespace strategy { namespace buffer +{ + +template +< + typename FormulaPolicy = strategy::andoyer, + typename Spheroid = srs::spheroid<double>, + typename CalculationType = void +> +class geographic_join_round +{ +public : + + //! \brief Constructs the strategy with a spheroid + //! \param spheroid The spheroid to be used + //! \param points_per_circle Number of points (minimum 4) that would be used for a full circle + explicit inline geographic_join_round(Spheroid const& spheroid, + std::size_t points_per_circle = default_points_per_circle) + : m_spheroid(spheroid) + , m_points_per_circle(get_point_count_for_join(points_per_circle)) + {} + + //! \brief Constructs the strategy + //! \param points_per_circle Number of points (minimum 4) that would be used for a full circle + explicit inline geographic_join_round(std::size_t points_per_circle = default_points_per_circle) + : m_points_per_circle(get_point_count_for_join(points_per_circle)) + {} + +#ifndef DOXYGEN_SHOULD_SKIP_THIS + //! Fills output_range with a rounded shape around a vertex + template <typename Point, typename DistanceType, typename RangeOut> + inline bool apply(Point const& /*ip*/, Point const& vertex, + Point const& perp1, Point const& perp2, + DistanceType const& buffer_distance, + RangeOut& range_out) const + { + using calc_t = typename select_calculation_type + < + Point, + typename boost::range_value<RangeOut>::type, + CalculationType + >::type; + + using helper = geographic_buffer_helper<FormulaPolicy, calc_t>; + + calc_t const lon_rad = get_as_radian<0>(vertex); + calc_t const lat_rad = get_as_radian<1>(vertex); + + calc_t first_azimuth; + calc_t angle_diff; + if (! helper::calculate_angles(lon_rad, lat_rad, perp1, perp2, m_spheroid, + angle_diff, first_azimuth)) + { + return false; + } + + static calc_t const two_pi = geometry::math::two_pi<calc_t>(); + calc_t const circle_fraction = angle_diff / two_pi; + std::size_t const n = (std::max)(static_cast<std::size_t>( + std::ceil(m_points_per_circle * circle_fraction)), std::size_t(1)); + + calc_t const diff = angle_diff / static_cast<calc_t>(n); + calc_t azi = math::wrap_azimuth_in_radian(first_azimuth + diff); + + range_out.push_back(perp1); + + // Generate points between 0 and n, not including them + // because perp1 and perp2 are inserted before and after this range. + for (std::size_t i = 1; i < n; i++) + { + helper::append_point(lon_rad, lat_rad, buffer_distance, azi, m_spheroid, range_out); + azi = math::wrap_azimuth_in_radian(azi + diff); + } + + range_out.push_back(perp2); + return true; + } + + template <typename NumericType> + static inline NumericType max_distance(NumericType const& distance) + { + return distance; + } + +#endif // DOXYGEN_SHOULD_SKIP_THIS + +private : + Spheroid m_spheroid; + std::size_t m_points_per_circle; +}; + +}} // namespace strategy::buffer + +}} // namespace boost::geometry + +#endif // BOOST_GEOMETRY_STRATEGIES_GEOGRAPHIC_BUFFER_JOIN_ROUND_HPP |