comparison DEPENDENCIES/generic/include/boost/geometry/strategies/spherical/ssf.hpp @ 16:2665513ce2d3

Add boost headers
author Chris Cannam
date Tue, 05 Aug 2014 11:11:38 +0100
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15:663ca0da4350 16:2665513ce2d3
1 // Boost.Geometry (aka GGL, Generic Geometry Library)
2
3 // Copyright (c) 2011-2012 Barend Gehrels, Amsterdam, the Netherlands.
4
5 // Use, modification and distribution is subject to the Boost Software License,
6 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
7 // http://www.boost.org/LICENSE_1_0.txt)
8
9 #ifndef BOOST_GEOMETRY_STRATEGIES_SPHERICAL_SSF_HPP
10 #define BOOST_GEOMETRY_STRATEGIES_SPHERICAL_SSF_HPP
11
12 #include <boost/mpl/if.hpp>
13 #include <boost/type_traits.hpp>
14
15 #include <boost/geometry/core/cs.hpp>
16 #include <boost/geometry/core/access.hpp>
17 #include <boost/geometry/core/radian_access.hpp>
18
19 #include <boost/geometry/util/select_coordinate_type.hpp>
20 #include <boost/geometry/util/math.hpp>
21
22 #include <boost/geometry/strategies/side.hpp>
23 //#include <boost/geometry/strategies/concepts/side_concept.hpp>
24
25
26 namespace boost { namespace geometry
27 {
28
29
30 namespace strategy { namespace side
31 {
32
33
34 /*!
35 \brief Check at which side of a Great Circle segment a point lies
36 left of segment (> 0), right of segment (< 0), on segment (0)
37 \ingroup strategies
38 \tparam CalculationType \tparam_calculation
39 */
40 template <typename CalculationType = void>
41 class spherical_side_formula
42 {
43
44 public :
45 template <typename P1, typename P2, typename P>
46 static inline int apply(P1 const& p1, P2 const& p2, P const& p)
47 {
48 typedef typename boost::mpl::if_c
49 <
50 boost::is_void<CalculationType>::type::value,
51
52 // Select at least a double...
53 typename select_most_precise
54 <
55 typename select_most_precise
56 <
57 typename select_most_precise
58 <
59 typename coordinate_type<P1>::type,
60 typename coordinate_type<P2>::type
61 >::type,
62 typename coordinate_type<P>::type
63 >::type,
64 double
65 >::type,
66 CalculationType
67 >::type coordinate_type;
68
69 // Convenient shortcuts
70 typedef coordinate_type ct;
71 ct const lambda1 = get_as_radian<0>(p1);
72 ct const delta1 = get_as_radian<1>(p1);
73 ct const lambda2 = get_as_radian<0>(p2);
74 ct const delta2 = get_as_radian<1>(p2);
75 ct const lambda = get_as_radian<0>(p);
76 ct const delta = get_as_radian<1>(p);
77
78 // Create temporary points (vectors) on unit a sphere
79 ct const cos_delta1 = cos(delta1);
80 ct const c1x = cos_delta1 * cos(lambda1);
81 ct const c1y = cos_delta1 * sin(lambda1);
82 ct const c1z = sin(delta1);
83
84 ct const cos_delta2 = cos(delta2);
85 ct const c2x = cos_delta2 * cos(lambda2);
86 ct const c2y = cos_delta2 * sin(lambda2);
87 ct const c2z = sin(delta2);
88
89 // (Third point is converted directly)
90 ct const cos_delta = cos(delta);
91
92 // Apply the "Spherical Side Formula" as presented on my blog
93 ct const dist
94 = (c1y * c2z - c1z * c2y) * cos_delta * cos(lambda)
95 + (c1z * c2x - c1x * c2z) * cos_delta * sin(lambda)
96 + (c1x * c2y - c1y * c2x) * sin(delta);
97
98 ct zero = ct();
99 return dist > zero ? 1
100 : dist < zero ? -1
101 : 0;
102 }
103 };
104
105
106 #ifndef DOXYGEN_NO_STRATEGY_SPECIALIZATIONS
107 namespace services
108 {
109
110 /*template <typename CalculationType>
111 struct default_strategy<spherical_polar_tag, CalculationType>
112 {
113 typedef spherical_side_formula<CalculationType> type;
114 };*/
115
116 template <typename CalculationType>
117 struct default_strategy<spherical_equatorial_tag, CalculationType>
118 {
119 typedef spherical_side_formula<CalculationType> type;
120 };
121
122 template <typename CalculationType>
123 struct default_strategy<geographic_tag, CalculationType>
124 {
125 typedef spherical_side_formula<CalculationType> type;
126 };
127
128 }
129 #endif
130
131 }} // namespace strategy::side
132
133 }} // namespace boost::geometry
134
135
136 #endif // BOOST_GEOMETRY_STRATEGIES_SPHERICAL_SSF_HPP