lsst.geom  16.0-2-ge920381
SpherePoint.h
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21 
22 #ifndef LSST_GEOM_SPHEREPOINT_H_
23 #define LSST_GEOM_SPHEREPOINT_H_
24 
25 #include <cmath>
26 #include <ostream>
27 #include <utility>
28 
30 #include "lsst/sphgeom/Vector3d.h"
31 #include "lsst/geom/Angle.h"
32 #include "lsst/geom/Point.h"
33 
34 namespace lsst {
35 namespace geom {
36 
57 class SpherePoint final {
58 public:
72  SpherePoint(Angle const& longitude, Angle const& latitude);
73 
88  SpherePoint(double longitude, double latitude, AngleUnit units);
89 
105  explicit SpherePoint(sphgeom::Vector3d const& vector);
106 
114  SpherePoint(sphgeom::LonLat const& lonLat);
115 
117  SpherePoint();
118 
126  SpherePoint(SpherePoint const& other) noexcept;
127 
134  SpherePoint(SpherePoint&& other) noexcept;
135 
136  ~SpherePoint();
137 
150  SpherePoint& operator=(SpherePoint const& other) noexcept;
151 
158  SpherePoint& operator=(SpherePoint&& other) noexcept;
159 
163  operator sphgeom::LonLat() const;
164 
165  /*
166  * Accessors
167  */
168 
176  Angle getLongitude() const noexcept { return _longitude * radians; };
177 
179  Angle getRa() const noexcept { return _longitude * radians; };
180 
188  Angle getLatitude() const noexcept { return _latitude * radians; };
189 
191  Angle getDec() const noexcept { return _latitude * radians; };
192 
198  Point2D getPosition(AngleUnit unit) const;
199 
207  sphgeom::UnitVector3d getVector() const noexcept;
208 
223  Angle operator[](size_t index) const;
224 
233  bool atPole() const noexcept {
234  // Unit tests indicate we don't need to worry about epsilon-errors, in that
235  // Objects constructed from lat=90*degrees, <0,0,1>, etc. all have atPole() = true.
236  return fabs(_latitude) >= HALFPI;
237  }
238 
248  bool isFinite() const noexcept;
249 
250  /*
251  * Comparisons between points
252  */
253 
274  bool operator==(SpherePoint const& other) const noexcept;
275 
282  bool operator!=(SpherePoint const& other) const noexcept;
283 
303  Angle bearingTo(SpherePoint const& other) const;
304 
314  Angle separation(SpherePoint const& other) const noexcept;
315 
316  /*
317  * Transformations of points
318  */
319 
331  SpherePoint rotated(SpherePoint const& axis, Angle const& amount) const noexcept;
332 
349  SpherePoint offset(Angle const& bearing, Angle const& amount) const;
350 
360 
361 private:
362  double _longitude; // radians
363  double _latitude; // radians
364 
366  void _set(sphgeom::UnitVector3d const& unitVector);
367 };
368 
377 
378 /*
379  * Object-level display
380  */
381 
402 std::ostream& operator<<(std::ostream& os, SpherePoint const& point);
403 
404 } // namespace geom
405 } // namespace lsst
406 
407 #endif /* LSST_GEOM_SPHEREPOINT_H_ */
bool operator==(SpherePoint const &other) const noexcept
true if two points have the same longitude and latitude.
Definition: SpherePoint.cc:145
bool isFinite() const noexcept
true if this point is a well-defined position.
Definition: SpherePoint.cc:143
std::pair< Angle, Angle > getTangentPlaneOffset(SpherePoint const &other) const
Get the offset from a tangent plane centered at this point to another point.
Definition: SpherePoint.cc:208
Angle bearingTo(SpherePoint const &other) const
Orientation at this point of the great circle arc to another point.
Definition: SpherePoint.cc:153
Angle getRa() const noexcept
Synonym for getLongitude.
Definition: SpherePoint.h:179
SpherePoint()
Construct a SpherePoint with "nan" for longitude and latitude.
Definition: SpherePoint.cc:107
Angle getLongitude() const noexcept
The longitude of this point.
Definition: SpherePoint.h:176
SpherePoint rotated(SpherePoint const &axis, Angle const &amount) const noexcept
Return a point rotated from this one around an axis.
Definition: SpherePoint.cc:172
sphgeom::UnitVector3d getVector() const noexcept
A unit vector representation of this point.
Definition: SpherePoint.cc:123
AngleUnit constexpr radians
constant with units of radians
Definition: Angle.h:105
A class representing an angle.
Definition: Angle.h:120
Angle operator[](size_t index) const
Longitude and latitude by index.
Definition: SpherePoint.cc:132
std::ostream & operator<<(std::ostream &os, SpherePoint const &point)
Print the value of a point to a stream.
Definition: SpherePoint.cc:247
Angle getDec() const noexcept
Synonym for getLatitude.
Definition: SpherePoint.h:191
Angle separation(SpherePoint const &other) const noexcept
Angular distance between two points.
Definition: SpherePoint.cc:167
Angle getLatitude() const noexcept
The latitude of this point.
Definition: SpherePoint.h:188
Point2D getPosition(AngleUnit unit) const
Return longitude, latitude as a Point2D object.
Definition: SpherePoint.cc:128
SpherePoint offset(Angle const &bearing, Angle const &amount) const
Return a point offset from this one along a great circle.
Definition: SpherePoint.cc:179
STL class.
SpherePoint & operator=(SpherePoint const &other) noexcept
Overwrite this object with the value of another SpherePoint.
Point in an unspecified spherical coordinate system.
Definition: SpherePoint.h:57
double constexpr HALFPI
Definition: Angle.h:41
bool atPole() const noexcept
true if this point is either coordinate pole.
Definition: SpherePoint.h:233
bool operator!=(SpherePoint const &other) const noexcept
false if two points represent the same position.
Definition: SpherePoint.cc:151
STL class.
A class used to convert scalar POD types such as double to Angle.
Definition: Angle.h:70
SpherePoint averageSpherePoint(std::vector< SpherePoint > const &coords)
Return the average of a list of coordinates.
Definition: SpherePoint.cc:229