vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/geometry/strategies/spherical/ssf.hpp

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// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2011-2012 Barend Gehrels, Amsterdam, the Netherlands.
// This file was modified by Oracle on 2016.
// Modifications copyright (c) 2016, Oracle and/or its affiliates.
// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
// 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_SPHERICAL_SSF_HPP
#define BOOST_GEOMETRY_STRATEGIES_SPHERICAL_SSF_HPP
#include <boost/geometry/core/cs.hpp>
#include <boost/geometry/core/access.hpp>
#include <boost/geometry/core/radian_access.hpp>
#include <boost/geometry/util/math.hpp>
#include <boost/geometry/util/promote_floating_point.hpp>
#include <boost/geometry/util/select_calculation_type.hpp>
#include <boost/geometry/strategies/side.hpp>
//#include <boost/geometry/strategies/concepts/side_concept.hpp>
namespace boost { namespace geometry
{
namespace strategy { namespace side
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail
{
template <typename T>
int spherical_side_formula(T const& lambda1, T const& delta1,
T const& lambda2, T const& delta2,
T const& lambda, T const& delta)
{
// Create temporary points (vectors) on unit a sphere
T const cos_delta1 = cos(delta1);
T const c1x = cos_delta1 * cos(lambda1);
T const c1y = cos_delta1 * sin(lambda1);
T const c1z = sin(delta1);
T const cos_delta2 = cos(delta2);
T const c2x = cos_delta2 * cos(lambda2);
T const c2y = cos_delta2 * sin(lambda2);
T const c2z = sin(delta2);
// (Third point is converted directly)
T const cos_delta = cos(delta);
// Apply the "Spherical Side Formula" as presented on my blog
T const dist
= (c1y * c2z - c1z * c2y) * cos_delta * cos(lambda)
+ (c1z * c2x - c1x * c2z) * cos_delta * sin(lambda)
+ (c1x * c2y - c1y * c2x) * sin(delta);
T zero = T();
return math::equals(dist, zero) ? 0
: dist > zero ? 1
: -1; // dist < zero
}
}
#endif // DOXYGEN_NO_DETAIL
/*!
\brief Check at which side of a Great Circle segment a point lies
left of segment (> 0), right of segment (< 0), on segment (0)
\ingroup strategies
\tparam CalculationType \tparam_calculation
*/
template <typename CalculationType = void>
class spherical_side_formula
{
public :
template <typename P1, typename P2, typename P>
static inline int apply(P1 const& p1, P2 const& p2, P const& p)
{
typedef typename promote_floating_point
<
typename select_calculation_type_alt
<
CalculationType,
P1, P2, P
>::type
>::type calculation_type;
calculation_type const lambda1 = get_as_radian<0>(p1);
calculation_type const delta1 = get_as_radian<1>(p1);
calculation_type const lambda2 = get_as_radian<0>(p2);
calculation_type const delta2 = get_as_radian<1>(p2);
calculation_type const lambda = get_as_radian<0>(p);
calculation_type const delta = get_as_radian<1>(p);
return detail::spherical_side_formula(lambda1, delta1,
lambda2, delta2,
lambda, delta);
}
};
#ifndef DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
namespace services
{
/*template <typename CalculationType>
struct default_strategy<spherical_polar_tag, CalculationType>
{
typedef spherical_side_formula<CalculationType> type;
};*/
template <typename CalculationType>
struct default_strategy<spherical_equatorial_tag, CalculationType>
{
typedef spherical_side_formula<CalculationType> type;
};
template <typename CalculationType>
struct default_strategy<geographic_tag, CalculationType>
{
typedef spherical_side_formula<CalculationType> type;
};
}
#endif
}} // namespace strategy::side
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_STRATEGIES_SPHERICAL_SSF_HPP