LSSTApplications  18.0.0+71,19.0.0+5,19.0.0+60,19.0.0+71,19.0.0+9,19.0.0-1-g20d9b18+27,19.0.0-1-g49a97f9+3,19.0.0-1-g5549ca4+4,19.0.0-1-g8c57eb9+27,19.0.0-1-g9a028c0+6,19.0.0-1-ga72da6b+3,19.0.0-1-gb77924a+7,19.0.0-1-gbfe0924+58,19.0.0-1-gd0f30f5+7,19.0.0-1-ge272bc4+27,19.0.0-1-gefe1d0d+42,19.0.0-13-g44bf2be,19.0.0-14-g983d7abd,19.0.0-15-g66e0b70,19.0.0-16-g98bbc9049,19.0.0-17-g9c22e3c+2,19.0.0-18-g2c901ce+2,19.0.0-19-g2772d4a+1,19.0.0-19-g85fbfd3+1,19.0.0-2-g0d9f9cd+66,19.0.0-2-g260436e+46,19.0.0-2-g361aba8+7,19.0.0-2-g9675b69+3,19.0.0-2-gde8e5e3+3,19.0.0-2-gff6972b+11,19.0.0-3-ga642a0f,19.0.0-4-g33ce3a3+8,19.0.0-4-gac56cce+9,19.0.0-4-gdb4f201+7,19.0.0-46-g6423acc,19.0.0-46-g8a917ba3+1,19.0.0-6-g28bbdb8,19.0.0-7-g3343160,19.0.0-7-g686a884+4,w.2020.16
LSSTDataManagementBasePackage
SpherePoint.h
Go to the documentation of this file.
1 /*
2  * Developed for the LSST Data Management System.
3  * This product includes software developed by the LSST Project
4  * (https://www.lsst.org).
5  * See the COPYRIGHT file at the top-level directory of this distribution
6  * for details of code ownership.
7  *
8  * This program is free software: you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation, either version 3 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program. If not, see <https://www.gnu.org/licenses/>.
20  */
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 
134  SpherePoint(SpherePoint&& other) noexcept;
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 
367 
368 private:
369  double _longitude; // radians
370  double _latitude; // radians
371 
373  void _set(sphgeom::UnitVector3d const& unitVector);
374 };
375 
384 
385 /*
386  * Object-level display
387  */
388 
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_ */
bool operator==(SpherePoint const &other) const noexcept
true if two points have the same longitude and latitude.
Definition: SpherePoint.cc:146
std::size_t hash_value() const noexcept
Return a hash of this object.
Definition: SpherePoint.cc:154
bool isFinite() const noexcept
true if this point is a well-defined position.
Definition: SpherePoint.cc:144
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
table::Key< lsst::geom::Angle > latitude
Definition: VisitInfo.cc:171
Angle bearingTo(SpherePoint const &other) const
Orientation at this point of the great circle arc to another point.
Definition: SpherePoint.cc:159
Point2D getPosition(AngleUnit unit) const noexcept
Return longitude, latitude as a Point2D object.
Definition: SpherePoint.cc:129
Angle getRa() const noexcept
Synonym for getLongitude.
Definition: SpherePoint.h:181
STL namespace.
Angle getLongitude() const noexcept
The longitude of this point.
Definition: SpherePoint.h:178
SpherePoint rotated(SpherePoint const &axis, Angle const &amount) const noexcept
Return a point rotated from this one around an axis.
Definition: SpherePoint.cc:178
sphgeom::UnitVector3d getVector() const noexcept
A unit vector representation of this point.
Definition: SpherePoint.cc:124
ItemVariant const * other
Definition: Schema.cc:56
Vector3d is a vector in ℝ³ with components stored in double precision.
Definition: Vector3d.h:44
AngleUnit constexpr radians
constant with units of radians
Definition: Angle.h:108
A class representing an angle.
Definition: Angle.h:127
Angle operator[](size_t index) const
Longitude and latitude by index.
Definition: SpherePoint.cc:133
std::ostream & operator<<(std::ostream &os, SpherePoint const &point)
Print the value of a point to a stream.
Definition: SpherePoint.cc:253
This file declares a class for representing vectors in ℝ³.
This file declares a class for representing unit vectors in ℝ³.
size_t operator()(argument_type const &x) const noexcept
Definition: SpherePoint.h:419
SpherePoint() noexcept
Construct a SpherePoint with "nan" for longitude and latitude.
Definition: SpherePoint.cc:108
A base class for image defects.
Angle getDec() const noexcept
Synonym for getLatitude.
Definition: SpherePoint.h:193
Angle separation(SpherePoint const &other) const noexcept
Angular distance between two points.
Definition: SpherePoint.cc:173
Angle getLatitude() const noexcept
The latitude of this point.
Definition: SpherePoint.h:190
SpherePoint offset(Angle const &bearing, Angle const &amount) const
Return a point offset from this one along a great circle.
Definition: SpherePoint.cc:185
double x
table::Key< lsst::geom::Angle > longitude
Definition: VisitInfo.cc:172
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
LonLat represents a spherical coordinate (longitude/latitude angle) pair.
Definition: LonLat.h:48
double constexpr HALFPI
Definition: Angle.h:41
bool atPole() const noexcept
true if this point is either coordinate pole.
Definition: SpherePoint.h:237
lsst::geom::SpherePoint SpherePoint
Definition: misc.h:35
UnitVector3d is a unit vector in ℝ³ with components stored in double precision.
Definition: UnitVector3d.h:55
bool operator!=(SpherePoint const &other) const noexcept
false if two points represent the same position.
Definition: SpherePoint.cc:152
std::ostream * os
Definition: Schema.cc:746
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:235