16 template<
class GeodType>
17 int PolygonAreaT<GeodType>::transit(
real lon1,
real lon2) {
29 lon12 > 0 && ((lon1 < 0 && lon2 >= 0) ||
31 (lon1 > 0 && lon2 == 0)) ? 1 :
33 (lon12 < 0 && lon1 >= 0 && lon2 < 0 ? -1 : 0);
44 template<
class GeodType>
45 int PolygonAreaT<GeodType>::transitdirect(
real lon1,
real lon2) {
59 return ( (lon2 >= 0 && lon2 <
Math::td ? 0 : 1) -
60 (lon1 >= 0 && lon1 <
Math::td ? 0 : 1) );
63 template<
class GeodType>
70 _earth.GenInverse(_lat1, _lon1, lat, lon, _mask,
71 s12, t, t, t, t, t, S12);
75 _crossings += transit(_lon1, lon);
77 _lat1 = lat; _lon1 = lon;
82 template<
class GeodType>
85 real lat, lon, S12, t;
86 _earth.GenDirect(_lat1, _lon1, azi,
false, s, _mask,
87 lat, lon, t, t, t, t, t, S12);
91 _crossings += transitdirect(_lon1, lon);
93 _lat1 = lat; _lon1 = lon;
98 template<
class GeodType>
100 real& perimeter, real& area)
const
110 perimeter = _perimetersum();
113 _earth.GenInverse(_lat1, _lon1, _lat0, _lon0, _mask,
114 s12, t, t, t, t, t, S12);
115 perimeter = _perimetersum(s12);
118 int crossings = _crossings + transit(_lon1, _lon0);
119 AreaReduce(tempsum, crossings, reverse, sign);
120 area =
real(0) + tempsum();
124 template<
class GeodType>
126 bool reverse,
bool sign,
127 real& perimeter, real& area)
const
135 perimeter = _perimetersum();
136 real tempsum = _polyline ? 0 : _areasum();
137 int crossings = _crossings;
138 unsigned num = _num + 1;
139 for (
int i = 0; i < (_polyline ? 1 : 2); ++i) {
141 _earth.GenInverse(i == 0 ? _lat1 : lat, i == 0 ? _lon1 : lon,
142 i != 0 ? _lat0 : lat, i != 0 ? _lon0 : lon,
143 _mask, s12, t, t, t, t, t, S12);
147 crossings += transit(i == 0 ? _lon1 : lon,
148 i != 0 ? _lon0 : lon);
155 AreaReduce(tempsum, crossings, reverse, sign);
160 template<
class GeodType>
162 bool reverse,
bool sign,
163 real& perimeter, real& area)
const
171 unsigned num = _num + 1;
172 perimeter = _perimetersum() + s;
176 real tempsum = _areasum();
177 int crossings = _crossings;
179 real lat, lon, s12, S12, t;
180 _earth.GenDirect(_lat1, _lon1, azi,
false, s, _mask,
181 lat, lon, t, t, t, t, t, S12);
183 crossings += transitdirect(_lon1, lon);
184 _earth.GenInverse(lat, lon, _lat0, _lon0, _mask,
185 s12, t, t, t, t, t, S12);
188 crossings += transit(lon, _lon0);
191 AreaReduce(tempsum, crossings, reverse, sign);
192 area =
real(0) + tempsum;
196 template<
class GeodType>
198 void PolygonAreaT<GeodType>::AreaReduce(T& area,
int crossings,
199 bool reverse,
bool sign)
const {
201 if (crossings & 1) area += (area < 0 ? 1 : -1) * _area0/2;
204 if (!reverse) area *= -1;
209 else if (area <= -_area0/2)
#define GEOGRAPHICLIB_EXPORT
GeographicLib::Math::real real
Header for GeographicLib::PolygonAreaT class.
static T AngNormalize(T x)
static constexpr int td
degrees per turn
static T AngDiff(T x, T y, T &e)
void AddPoint(real lat, real lon)
unsigned Compute(bool reverse, bool sign, real &perimeter, real &area) const
unsigned TestPoint(real lat, real lon, bool reverse, bool sign, real &perimeter, real &area) const
void AddEdge(real azi, real s)
unsigned TestEdge(real azi, real s, bool reverse, bool sign, real &perimeter, real &area) const
Namespace for GeographicLib.