1 // Copyright (C) 2006 Mathias Froehlich - Mathias.Froehlich@web.de
3 // This library is free software; you can redistribute it and/or
4 // modify it under the terms of the GNU Library General Public
5 // License as published by the Free Software Foundation; either
6 // version 2 of the License, or (at your option) any later version.
8 // This library is distributed in the hope that it will be useful,
9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 // Library General Public License for more details.
13 // You should have received a copy of the GNU General Public License
14 // along with this program; if not, write to the Free Software
15 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 #include <simgear/constants.h>
25 // #define SG_GEOD_NATIVE_DEGREE
27 /// Class representing a geodetic location
30 /// Default constructor, initializes the instance to lat = lon = elev = 0
33 /// Factory from angular values in radians and elevation is 0
34 static SGGeod fromRad(double lon, double lat);
35 /// Factory from angular values in degrees and elevation is 0
36 static SGGeod fromDeg(double lon, double lat);
37 /// Factory from angular values in radians and elevation in ft
38 static SGGeod fromRadFt(double lon, double lat, double elevation);
39 /// Factory from angular values in degrees and elevation in ft
40 static SGGeod fromDegFt(double lon, double lat, double elevation);
41 /// Factory from angular values in radians and elevation in m
42 static SGGeod fromRadM(double lon, double lat, double elevation);
43 /// Factory from angular values in degrees and elevation in m
44 static SGGeod fromDegM(double lon, double lat, double elevation);
45 /// Factory to convert position from a cartesian position assumed to be
46 /// in wgs84 measured in meters
47 /// Note that this conversion is relatively expensive to compute
48 static SGGeod fromCart(const SGVec3<double>& cart);
49 /// Factory to convert position from a geocentric position
50 /// Note that this conversion is relatively expensive to compute
51 static SGGeod fromGeoc(const SGGeoc& geoc);
53 /// Return the geodetic longitude in radians
54 double getLongitudeRad(void) const;
55 /// Set the geodetic longitude from the argument given in radians
56 void setLongitudeRad(double lon);
58 /// Return the geodetic longitude in degrees
59 double getLongitudeDeg(void) const;
60 /// Set the geodetic longitude from the argument given in degrees
61 void setLongitudeDeg(double lon);
63 /// Return the geodetic latitude in radians
64 double getLatitudeRad(void) const;
65 /// Set the geodetic latitude from the argument given in radians
66 void setLatitudeRad(double lat);
68 /// Return the geodetic latitude in degrees
69 double getLatitudeDeg(void) const;
70 /// Set the geodetic latitude from the argument given in degrees
71 void setLatitudeDeg(double lat);
73 /// Return the geodetic elevation in meters
74 double getElevationM(void) const;
75 /// Set the geodetic elevation from the argument given in meters
76 void setElevationM(double elevation);
78 /// Return the geodetic elevation in feet
79 double getElevationFt(void) const;
80 /// Set the geodetic elevation from the argument given in feet
81 void setElevationFt(double elevation);
83 // Create a local coordinate frame in the earth-centered frame of
84 // reference. X points north, Z points down.
85 // makeSimulationFrameRelative() only includes rotation.
87 osg::Matrix makeSimulationFrameRelative();
88 osg::Matrix makeSimulationFrame();
90 // Create a Z-up local coordinate frame in the earth-centered frame
91 // of reference. This is what scenery models, etc. expect.
92 // makeZUpFrameRelative() only includes rotation.
93 osg::Matrix makeZUpFrameRelative();
94 osg::Matrix makeZUpFrame();
96 /// This one is private since construction is not unique if you do
97 /// not know the units of the arguments. Use the factory methods for
99 SGGeod(double lon, double lat, double elevation);
101 /// The actual data, angles in degree, elevation in meters
102 /// The rationale for storing the values in degrees is that most code places
103 /// in flightgear/terragear use degrees as a nativ input and output value.
104 /// The places where it makes sense to use radians is when we convert
105 /// to other representations or compute rotation matrices. But both tasks
106 /// are computionally intensive anyway and that additional 'toRadian'
107 /// conversion does not hurt too much
114 SGGeod::SGGeod(void) :
115 _lon(0), _lat(0), _elevation(0)
120 SGGeod::SGGeod(double lon, double lat, double elevation) :
121 _lon(lon), _lat(lat), _elevation(elevation)
127 SGGeod::fromRad(double lon, double lat)
129 #ifdef SG_GEOD_NATIVE_DEGREE
130 return SGGeod(lon*SGD_RADIANS_TO_DEGREES, lat*SGD_RADIANS_TO_DEGREES, 0);
132 return SGGeod(lon, lat, 0);
138 SGGeod::fromDeg(double lon, double lat)
140 #ifdef SG_GEOD_NATIVE_DEGREE
141 return SGGeod(lon, lat, 0);
143 return SGGeod(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0);
149 SGGeod::fromRadFt(double lon, double lat, double elevation)
151 #ifdef SG_GEOD_NATIVE_DEGREE
152 return SGGeod(lon*SGD_RADIANS_TO_DEGREES, lat*SGD_RADIANS_TO_DEGREES,
153 elevation*SG_FEET_TO_METER);
155 return SGGeod(lon, lat, elevation*SG_FEET_TO_METER);
161 SGGeod::fromDegFt(double lon, double lat, double elevation)
163 #ifdef SG_GEOD_NATIVE_DEGREE
164 return SGGeod(lon, lat, elevation*SG_FEET_TO_METER);
166 return SGGeod(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS,
167 elevation*SG_FEET_TO_METER);
173 SGGeod::fromRadM(double lon, double lat, double elevation)
175 #ifdef SG_GEOD_NATIVE_DEGREE
176 return SGGeod(lon*SGD_RADIANS_TO_DEGREES, lat*SGD_RADIANS_TO_DEGREES,
179 return SGGeod(lon, lat, elevation);
185 SGGeod::fromDegM(double lon, double lat, double elevation)
187 #ifdef SG_GEOD_NATIVE_DEGREE
188 return SGGeod(lon, lat, elevation);
190 return SGGeod(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS,
197 SGGeod::fromCart(const SGVec3<double>& cart)
200 SGGeodesy::SGCartToGeod(cart, geod);
206 SGGeod::fromGeoc(const SGGeoc& geoc)
209 SGGeodesy::SGGeocToCart(geoc, cart);
211 SGGeodesy::SGCartToGeod(cart, geod);
217 SGGeod::getLongitudeRad(void) const
219 #ifdef SG_GEOD_NATIVE_DEGREE
220 return _lon*SGD_DEGREES_TO_RADIANS;
228 SGGeod::setLongitudeRad(double lon)
230 #ifdef SG_GEOD_NATIVE_DEGREE
231 _lon = lon*SGD_RADIANS_TO_DEGREES;
239 SGGeod::getLongitudeDeg(void) const
241 #ifdef SG_GEOD_NATIVE_DEGREE
244 return _lon*SGD_RADIANS_TO_DEGREES;
250 SGGeod::setLongitudeDeg(double lon)
252 #ifdef SG_GEOD_NATIVE_DEGREE
255 _lon = lon*SGD_DEGREES_TO_RADIANS;
261 SGGeod::getLatitudeRad(void) const
263 #ifdef SG_GEOD_NATIVE_DEGREE
264 return _lat*SGD_DEGREES_TO_RADIANS;
272 SGGeod::setLatitudeRad(double lat)
274 #ifdef SG_GEOD_NATIVE_DEGREE
275 _lat = lat*SGD_RADIANS_TO_DEGREES;
283 SGGeod::getLatitudeDeg(void) const
285 #ifdef SG_GEOD_NATIVE_DEGREE
288 return _lat*SGD_RADIANS_TO_DEGREES;
294 SGGeod::setLatitudeDeg(double lat)
296 #ifdef SG_GEOD_NATIVE_DEGREE
299 _lat = lat*SGD_DEGREES_TO_RADIANS;
305 SGGeod::getElevationM(void) const
312 SGGeod::setElevationM(double elevation)
314 _elevation = elevation;
319 SGGeod::getElevationFt(void) const
321 return _elevation*SG_METER_TO_FEET;
326 SGGeod::setElevationFt(double elevation)
328 _elevation = elevation*SG_FEET_TO_METER;
331 /// Output to an ostream
332 template<typename char_type, typename traits_type>
334 std::basic_ostream<char_type, traits_type>&
335 operator<<(std::basic_ostream<char_type, traits_type>& s, const SGGeod& g)
337 return s << "lon = " << g.getLongitudeDeg()
338 << "deg, lat = " << g.getLatitudeDeg()
339 << "deg, elev = " << g.getElevationM()