PostGIS  2.2.8dev-r@@SVN_REVISION@@
lwgeodetic.h
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1 /**********************************************************************
2  *
3  * PostGIS - Spatial Types for PostgreSQL
4  * Copyright 2009 Paul Ramsey <pramsey@cleverelephant.ca>
5  *
6  * This is free software; you can redistribute and/or modify it under
7  * the terms of the GNU General Public Licence. See the COPYING file.
8  *
9  **********************************************************************/
10 
11 #ifndef _LWGEODETIC_H
12 #define _LWGEODETIC_H 1
13 
14 /* For NAN */
15 #ifndef _GNU_SOURCE
16 #define _GNU_SOURCE
17 #endif
18 
19 #include <math.h>
20 
21 #ifndef NAN
22 #define NAN 0.0/0.0
23 #endif
24 
25 extern int gbox_geocentric_slow;
26 
27 #define POW2(x) ((x)*(x))
28 
32 typedef struct
33 {
34  double lon;
35  double lat;
37 
41 typedef struct
42 {
46 
50 typedef struct
51 {
52  double measure;
53  uint32_t index;
55 
59 #define deg2rad(d) (M_PI * (d) / 180.0)
60 #define rad2deg(r) (180.0 * (r) / M_PI)
61 
62 
66 #define PIR_NO_INTERACT 0x00
67 #define PIR_INTERSECTS 0x01
68 #define PIR_COLINEAR 0x02
69 #define PIR_A_TOUCH_RIGHT 0x04
70 #define PIR_A_TOUCH_LEFT 0x08
71 #define PIR_B_TOUCH_RIGHT 0x10
72 #define PIR_B_TOUCH_LEFT 0x20
73 
74 
75 /*
76 * Geodetic calculations
77 */
78 void geog2cart(const GEOGRAPHIC_POINT *g, POINT3D *p);
79 void cart2geog(const POINT3D *p, GEOGRAPHIC_POINT *g);
81 void x_to_z(POINT3D *p);
82 void y_to_z(POINT3D *p);
87 double z_to_latitude(double z, int top);
88 int clairaut_cartesian(const POINT3D *start, const POINT3D *end, GEOGRAPHIC_POINT *g_top, GEOGRAPHIC_POINT *g_bottom);
89 int clairaut_geographic(const GEOGRAPHIC_POINT *start, const GEOGRAPHIC_POINT *end, GEOGRAPHIC_POINT *g_top, GEOGRAPHIC_POINT *g_bottom);
90 double sphere_distance(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e);
91 double sphere_distance_cartesian(const POINT3D *s, const POINT3D *e);
92 int sphere_project(const GEOGRAPHIC_POINT *r, double distance, double azimuth, GEOGRAPHIC_POINT *n);
93 int edge_calculate_gbox_slow(const GEOGRAPHIC_EDGE *e, GBOX *gbox);
94 int edge_calculate_gbox(const POINT3D *A1, const POINT3D *A2, GBOX *gbox);
96 int edge_intersects(const POINT3D *A1, const POINT3D *A2, const POINT3D *B1, const POINT3D *B2);
97 double edge_distance_to_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *gp, GEOGRAPHIC_POINT *closest);
98 double edge_distance_to_edge(const GEOGRAPHIC_EDGE *e1, const GEOGRAPHIC_EDGE *e2, GEOGRAPHIC_POINT *closest1, GEOGRAPHIC_POINT *closest2);
99 void geographic_point_init(double lon, double lat, GEOGRAPHIC_POINT *g);
100 int ptarray_contains_point_sphere(const POINTARRAY *pa, const POINT2D *pt_outside, const POINT2D *pt_to_test);
101 int lwpoly_covers_point2d(const LWPOLY *poly, const POINT2D *pt_to_test);
102 void lwpoly_pt_outside(const LWPOLY *poly, POINT2D *pt_outside);
103 int ptarray_point_in_ring(const POINTARRAY *pa, const POINT2D *pt_outside, const POINT2D *pt_to_test);
104 double ptarray_area_sphere(const POINTARRAY *pa);
105 double latitude_degrees_normalize(double lat);
106 double longitude_degrees_normalize(double lon);
107 double ptarray_length_spheroid(const POINTARRAY *pa, const SPHEROID *s);
110 void point_shift(GEOGRAPHIC_POINT *p, double shift);
111 double longitude_radians_normalize(double lon);
112 double latitude_radians_normalize(double lat);
113 void vector_sum(const POINT3D *a, const POINT3D *b, POINT3D *n);
114 double vector_angle(const POINT3D* v1, const POINT3D* v2);
115 void vector_rotate(const POINT3D* v1, const POINT3D* v2, double angle, POINT3D* n);
116 void normalize(POINT3D *p);
117 void unit_normal(const POINT3D *P1, const POINT3D *P2, POINT3D *normal);
118 double sphere_direction(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e, double d);
119 void ll2cart(const POINT2D *g, POINT3D *p);
120 
121 /*
122 ** Prototypes for spheroid functions.
123 */
124 double spheroid_distance(const GEOGRAPHIC_POINT *a, const GEOGRAPHIC_POINT *b, const SPHEROID *spheroid);
125 double spheroid_direction(const GEOGRAPHIC_POINT *r, const GEOGRAPHIC_POINT *s, const SPHEROID *spheroid);
126 int spheroid_project(const GEOGRAPHIC_POINT *r, const SPHEROID *spheroid, double distance, double azimuth, GEOGRAPHIC_POINT *g);
127 
128 
129 #endif /* _LWGEODETIC_H */
130 
131 
132 
double sphere_distance(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e)
Given two points on a unit sphere, calculate their distance apart in radians.
Definition: lwgeodetic.c:898
void robust_cross_product(const GEOGRAPHIC_POINT *p, const GEOGRAPHIC_POINT *q, POINT3D *a)
Computes the cross product of two vectors using their lat, lng representations.
Definition: lwgeodetic.c:584
double edge_distance_to_edge(const GEOGRAPHIC_EDGE *e1, const GEOGRAPHIC_EDGE *e2, GEOGRAPHIC_POINT *closest1, GEOGRAPHIC_POINT *closest2)
Calculate the distance between two edges.
Definition: lwgeodetic.c:1217
double longitude_radians_normalize(double lon)
Convert a longitude to the range of -PI,PI.
Definition: lwgeodetic.c:26
int sphere_project(const GEOGRAPHIC_POINT *r, double distance, double azimuth, GEOGRAPHIC_POINT *n)
Given a starting location r, a distance and an azimuth to the new point, compute the location of the ...
Definition: lwgeodetic.c:1262
Two-point great circle segment from a to b.
Definition: lwgeodetic.h:41
double spheroid_direction(const GEOGRAPHIC_POINT *r, const GEOGRAPHIC_POINT *s, const SPHEROID *spheroid)
Computes the direction of the geodesic joining two points on the spheroid.
Definition: lwspheroid.c:268
char * r
Definition: cu_in_wkt.c:24
int edge_contains_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *p)
Returns true if the point p is on the minor edge defined by the end points of e.
Definition: lwgeodetic.c:982
void normalize(POINT3D *p)
Normalize to a unit vector.
Definition: lwgeodetic.c:565
int crosses_dateline(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e)
Definition: lwgeodetic.c:616
double z_to_latitude(double z, int top)
Used in great circle to compute the pole of the great circle.
Definition: lwgeodetic.c:997
double measure
Definition: lwgeodetic.h:52
void cart2geog(const POINT3D *p, GEOGRAPHIC_POINT *g)
Convert cartesion coordinates on unit sphere to spherical coordinates.
Definition: lwgeodetic.c:364
int edge_calculate_gbox_slow(const GEOGRAPHIC_EDGE *e, GBOX *gbox)
Definition: lwgeodetic.c:1292
void point_shift(GEOGRAPHIC_POINT *p, double shift)
Shift a point around by a number of radians.
Definition: lwgeodetic.c:136
void y_to_z(POINT3D *p)
Definition: lwgeodetic.c:608
double longitude_degrees_normalize(double lon)
Convert a longitude to the range of -180,180.
Definition: lwgeodetic.c:82
Point in spherical coordinates on the world.
Definition: lwgeodetic.h:32
int spheroid_project(const GEOGRAPHIC_POINT *r, const SPHEROID *spheroid, double distance, double azimuth, GEOGRAPHIC_POINT *g)
Given a location, an azimuth and a distance, computes the location of the projected point...
Definition: lwspheroid.c:345
double latitude_degrees_normalize(double lat)
Convert a latitude to the range of -90,90.
Definition: lwgeodetic.c:109
int clairaut_geographic(const GEOGRAPHIC_POINT *start, const GEOGRAPHIC_POINT *end, GEOGRAPHIC_POINT *g_top, GEOGRAPHIC_POINT *g_bottom)
Computes the pole of the great circle disk which is the intersection of the great circle with the lin...
Definition: lwgeodetic.c:1049
void unit_normal(const POINT3D *P1, const POINT3D *P2, POINT3D *normal)
Calculates the unit normal to two vectors, trying to avoid problems with over-narrow or over-wide cas...
Definition: lwgeodetic.c:491
int ptarray_contains_point_sphere(const POINTARRAY *pa, const POINT2D *pt_outside, const POINT2D *pt_to_test)
This routine returns LW_TRUE if the stabline joining the pt_outside and pt_to_test crosses the ring a...
Definition: lwgeodetic.c:3204
GEOGRAPHIC_POINT start
Definition: lwgeodetic.h:43
double edge_distance_to_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *gp, GEOGRAPHIC_POINT *closest)
Definition: lwgeodetic.c:1166
int edge_point_in_cone(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *p)
Returns true if the point p is inside the cone defined by the two ends of the edge e...
Definition: lwgeodetic.c:738
int clairaut_cartesian(const POINT3D *start, const POINT3D *end, GEOGRAPHIC_POINT *g_top, GEOGRAPHIC_POINT *g_bottom)
Computes the pole of the great circle disk which is the intersection of the great circle with the lin...
Definition: lwgeodetic.c:1024
uint32_t index
Definition: lwgeodetic.h:53
int edge_contains_coplanar_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *p)
True if the longitude of p is within the range of the longitude of the ends of e. ...
Definition: lwgeodetic.c:785
void x_to_z(POINT3D *p)
Definition: lwgeodetic.c:601
double ptarray_length_spheroid(const POINTARRAY *pa, const SPHEROID *s)
Definition: lwgeodetic.c:2831
void ll2cart(const POINT2D *g, POINT3D *p)
Convert lon/lat coordinates to cartesion coordinates on unit sphere.
Definition: lwgeodetic.c:373
void vector_rotate(const POINT3D *v1, const POINT3D *v2, double angle, POINT3D *n)
Rotates v1 through an angle (in radians) within the plane defined by v1/v2, returns the rotated vecto...
Definition: lwgeodetic.c:523
void lwpoly_pt_outside(const LWPOLY *poly, POINT2D *pt_outside)
Definition: lwgeodetic.c:1423
GEOGRAPHIC_POINT end
Definition: lwgeodetic.h:44
char * s
Definition: cu_in_wkt.c:23
Datum distance(PG_FUNCTION_ARGS)
void geog2cart(const GEOGRAPHIC_POINT *g, POINT3D *p)
Convert spherical coordinates to cartesion coordinates on unit sphere.
Definition: lwgeodetic.c:354
int gbox_geocentric_slow
For testing geodetic bounding box, we have a magic global variable.
Definition: lwgeodetic.c:21
int edge_intersects(const POINT3D *A1, const POINT3D *A2, const POINT3D *B1, const POINT3D *B2)
Returns non-zero if edges A and B interact.
Definition: lwgeodetic.c:3099
void vector_sum(const POINT3D *a, const POINT3D *b, POINT3D *n)
Calculate the sum of two vectors.
Definition: lwgeodetic.c:415
double latitude_radians_normalize(double lat)
Convert a latitude to the range of -PI/2,PI/2.
Definition: lwgeodetic.c:54
double sphere_distance_cartesian(const POINT3D *s, const POINT3D *e)
Given two unit vectors, calculate their distance apart in radians.
Definition: lwgeodetic.c:917
int geographic_point_equals(const GEOGRAPHIC_POINT *g1, const GEOGRAPHIC_POINT *g2)
Definition: lwgeodetic.c:146
Holder for sorting points in distance algorithm.
Definition: lwgeodetic.h:50
double ptarray_area_sphere(const POINTARRAY *pa)
Returns the area of the ring (ring must be closed) in square radians (surface of the sphere is 4*PI)...
Definition: lwgeodetic.c:1703
void geographic_point_init(double lon, double lat, GEOGRAPHIC_POINT *g)
Initialize a geographic point.
Definition: lwgeodetic.c:156
int ptarray_point_in_ring(const POINTARRAY *pa, const POINT2D *pt_outside, const POINT2D *pt_to_test)
double spheroid_distance(const GEOGRAPHIC_POINT *a, const GEOGRAPHIC_POINT *b, const SPHEROID *spheroid)
Computes the shortest distance along the surface of the spheroid between two points.
Definition: lwspheroid.c:172
int lwpoly_covers_point2d(const LWPOLY *poly, const POINT2D *pt_to_test)
Given a polygon (lon/lat decimal degrees) and point (lon/lat decimal degrees) and a guaranteed outsid...
Definition: lwgeodetic.c:2387
double vector_angle(const POINT3D *v1, const POINT3D *v2)
Angle between two unit vectors.
Definition: lwgeodetic.c:455
int edge_calculate_gbox(const POINT3D *A1, const POINT3D *A2, GBOX *gbox)
The magic function, given an edge in spherical coordinates, calculate a 3D bounding box that fully co...
Definition: lwgeodetic.c:1356
int edge_point_on_plane(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *p)
Returns true if the point p is on the great circle plane.
Definition: lwgeodetic.c:725
int edge_intersection(const GEOGRAPHIC_EDGE *e1, const GEOGRAPHIC_EDGE *e2, GEOGRAPHIC_POINT *g)
Returns true if an intersection can be calculated, and places it in *g.
Definition: lwgeodetic.c:1075
double sphere_direction(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e, double d)
Given two points on a unit sphere, calculate the direction from s to e.
Definition: lwgeodetic.c:925