LSSTApplications  20.0.0
LSSTDataManagementBasePackage
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) noexcept;
115 
117  SpherePoint() noexcept;
118 
126  SpherePoint(SpherePoint const& other) noexcept;
127 
135 
136  ~SpherePoint() noexcept;
137 
150  SpherePoint& operator=(SpherePoint const& other) noexcept;
151 
158  SpherePoint& operator=(SpherePoint&& other) noexcept;
159 
165  operator sphgeom::LonLat() const noexcept;
166 
167  /*
168  * Accessors
169  */
170 
178  Angle getLongitude() const noexcept { return _longitude * radians; };
179 
181  Angle getRa() const noexcept { return _longitude * radians; };
182 
190  Angle getLatitude() const noexcept { return _latitude * radians; };
191 
193  Angle getDec() const noexcept { return _latitude * radians; };
194 
202  Point2D getPosition(AngleUnit unit) const noexcept;
203 
211  sphgeom::UnitVector3d getVector() const noexcept;
212 
227  Angle operator[](size_t index) const;
228 
237  bool atPole() const noexcept {
238  // Unit tests indicate we don't need to worry about epsilon-errors, in that
239  // Objects constructed from lat=90*degrees, <0,0,1>, etc. all have atPole() = true.
240  return fabs(_latitude) >= HALFPI;
241  }
242 
252  bool isFinite() const noexcept;
253 
254  /*
255  * Comparisons between points
256  */
257 
278  bool operator==(SpherePoint const& other) const noexcept;
279 
286  bool operator!=(SpherePoint const& other) const noexcept;
287 
289  std::size_t hash_value() const noexcept;
290 
310  Angle bearingTo(SpherePoint const& other) const;
311 
321  Angle separation(SpherePoint const& other) const noexcept;
322 
323  /*
324  * Transformations of points
325  */
326 
338  SpherePoint rotated(SpherePoint const& axis, Angle const& amount) const noexcept;
339 
356  SpherePoint offset(Angle const& bearing, Angle const& amount) const;
357 
366  std::pair<Angle, Angle> getTangentPlaneOffset(SpherePoint const& other) const;
367 
368 private:
369  double _longitude; // radians
370  double _latitude; // radians
371 
373  void _set(sphgeom::UnitVector3d const& unitVector);
374 };
375 
383 SpherePoint averageSpherePoint(std::vector<SpherePoint> const& coords);
384 
385 /*
386  * Object-level display
387  */
388 
409 std::ostream& operator<<(std::ostream& os, SpherePoint const& point);
410 
411 } // namespace geom
412 } // namespace lsst
413 
414 namespace std {
415 template <>
419  size_t operator()(argument_type const& x) const noexcept { return x.hash_value(); }
420 };
421 } // namespace std
422 
423 #endif /* LSST_GEOM_SPHEREPOINT_H_ */
lsst::geom::averageSpherePoint
SpherePoint averageSpherePoint(std::vector< SpherePoint > const &coords)
Return the average of a list of coordinates.
Definition: SpherePoint.cc:235
lsst::geom::SpherePoint::getPosition
Point2D getPosition(AngleUnit unit) const noexcept
Return longitude, latitude as a Point2D object.
Definition: SpherePoint.cc:129
lsst::afw::table::SpherePoint
lsst::geom::SpherePoint SpherePoint
Definition: misc.h:35
UnitVector3d.h
This file declares a class for representing unit vectors in ℝ³.
lsst::geom::SpherePoint::hash_value
std::size_t hash_value() const noexcept
Return a hash of this object.
Definition: SpherePoint.cc:154
lsst::sphgeom::LonLat
LonLat represents a spherical coordinate (longitude/latitude angle) pair.
Definition: LonLat.h:48
lsst::geom::SpherePoint::separation
Angle separation(SpherePoint const &other) const noexcept
Angular distance between two points.
Definition: SpherePoint.cc:173
lsst::geom::SpherePoint::SpherePoint
SpherePoint() noexcept
Construct a SpherePoint with "nan" for longitude and latitude.
Definition: SpherePoint.cc:108
lsst::geom::SpherePoint::getLongitude
Angle getLongitude() const noexcept
The longitude of this point.
Definition: SpherePoint.h:178
lsst::geom::SpherePoint::SpherePoint
SpherePoint(SpherePoint &&other) noexcept
Create a copy of a SpherePoint.
std::hash< lsst::geom::SpherePoint >::operator()
size_t operator()(argument_type const &x) const noexcept
Definition: SpherePoint.h:419
lsst::geom::SpherePoint::getTangentPlaneOffset
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:214
lsst::geom::SpherePoint::getRa
Angle getRa() const noexcept
Synonym for getLongitude.
Definition: SpherePoint.h:181
lsst::sphgeom::Vector3d
Vector3d is a vector in ℝ³ with components stored in double precision.
Definition: Vector3d.h:44
lsst::sphgeom::UnitVector3d
UnitVector3d is a unit vector in ℝ³ with components stored in double precision.
Definition: UnitVector3d.h:55
lsst::geom::SpherePoint::getVector
sphgeom::UnitVector3d getVector() const noexcept
A unit vector representation of this point.
Definition: SpherePoint.cc:124
lsst::geom::SpherePoint::bearingTo
Angle bearingTo(SpherePoint const &other) const
Orientation at this point of the great circle arc to another point.
Definition: SpherePoint.cc:159
Angle.h
x
double x
Definition: ChebyshevBoundedField.cc:277
lsst::geom::SpherePoint::rotated
SpherePoint rotated(SpherePoint const &axis, Angle const &amount) const noexcept
Return a point rotated from this one around an axis.
Definition: SpherePoint.cc:178
lsst::geom::SpherePoint::getDec
Angle getDec() const noexcept
Synonym for getLatitude.
Definition: SpherePoint.h:193
Vector3d.h
This file declares a class for representing vectors in ℝ³.
other
ItemVariant const * other
Definition: Schema.cc:56
lsst::geom::SpherePoint::atPole
bool atPole() const noexcept
true if this point is either coordinate pole.
Definition: SpherePoint.h:237
lsst
A base class for image defects.
Definition: imageAlgorithm.dox:1
lsst::geom
Definition: geomOperators.dox:4
os
std::ostream * os
Definition: Schema.cc:746
std
STL namespace.
lsst::geom::Point< double, 2 >
lsst::geom::SpherePoint::SpherePoint
SpherePoint(SpherePoint const &other) noexcept
Create a copy of a SpherePoint.
lsst::geom::AngleUnit
A class used to convert scalar POD types such as double to Angle.
Definition: Angle.h:70
lsst::geom::Angle
A class representing an angle.
Definition: Angle.h:127
lsst::geom::SpherePoint::getLatitude
Angle getLatitude() const noexcept
The latitude of this point.
Definition: SpherePoint.h:190
lsst::geom::radians
constexpr AngleUnit radians
constant with units of radians
Definition: Angle.h:108
lsst::geom::SpherePoint::isFinite
bool isFinite() const noexcept
true if this point is a well-defined position.
Definition: SpherePoint.cc:144
std::size_t
Point.h
longitude
table::Key< lsst::geom::Angle > longitude
Definition: VisitInfo.cc:172
lsst::geom::SpherePoint
Point in an unspecified spherical coordinate system.
Definition: SpherePoint.h:57
latitude
table::Key< lsst::geom::Angle > latitude
Definition: VisitInfo.cc:171
lsst::geom::SpherePoint::offset
SpherePoint offset(Angle const &bearing, Angle const &amount) const
Return a point offset from this one along a great circle.
Definition: SpherePoint.cc:185
lsst::geom::SpherePoint::~SpherePoint
~SpherePoint() noexcept
lsst::geom::HALFPI
constexpr double HALFPI
Definition: Angle.h:41
std::hash