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lwgeodetic.h
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24 
25 
26 #ifndef _LWGEODETIC_H
27 #define _LWGEODETIC_H 1
28 
29 /* For NAN */
30 #ifndef _GNU_SOURCE
31 #define _GNU_SOURCE
32 #endif
33 
34 #include <math.h>
35 
36 #ifndef NAN
37 #define NAN 0.0/0.0
38 #endif
39 
40 extern int gbox_geocentric_slow;
41 
42 #define POW2(x) ((x)*(x))
43 
47 typedef struct
48 {
49  double lon;
50  double lat;
52 
56 typedef struct
57 {
61 
65 typedef struct
66 {
67  double measure;
70 
74 #define deg2rad(d) (M_PI * (d) / 180.0)
75 #define rad2deg(r) (180.0 * (r) / M_PI)
76 
77 
81 #define PIR_NO_INTERACT 0x00
82 #define PIR_INTERSECTS 0x01
83 #define PIR_COLINEAR 0x02
84 #define PIR_A_TOUCH_RIGHT 0x04
85 #define PIR_A_TOUCH_LEFT 0x08
86 #define PIR_B_TOUCH_RIGHT 0x10
87 #define PIR_B_TOUCH_LEFT 0x20
88 
89 
90 /*
91 * Geodetic calculations
92 */
93 void geog2cart(const GEOGRAPHIC_POINT *g, POINT3D *p);
94 void cart2geog(const POINT3D *p, GEOGRAPHIC_POINT *g);
96 void x_to_z(POINT3D *p);
97 void y_to_z(POINT3D *p);
102 double z_to_latitude(double z, int top);
103 int clairaut_cartesian(const POINT3D *start, const POINT3D *end, GEOGRAPHIC_POINT *g_top, GEOGRAPHIC_POINT *g_bottom);
104 int clairaut_geographic(const GEOGRAPHIC_POINT *start, const GEOGRAPHIC_POINT *end, GEOGRAPHIC_POINT *g_top, GEOGRAPHIC_POINT *g_bottom);
105 double sphere_distance(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e);
106 double sphere_distance_cartesian(const POINT3D *s, const POINT3D *e);
107 int sphere_project(const GEOGRAPHIC_POINT *r, double distance, double azimuth, GEOGRAPHIC_POINT *n);
108 int edge_calculate_gbox_slow(const GEOGRAPHIC_EDGE *e, GBOX *gbox);
109 int edge_calculate_gbox(const POINT3D *A1, const POINT3D *A2, GBOX *gbox);
111 uint32_t edge_intersects(const POINT3D *A1, const POINT3D *A2, const POINT3D *B1, const POINT3D *B2);
112 double edge_distance_to_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *gp, GEOGRAPHIC_POINT *closest);
113 double edge_distance_to_edge(const GEOGRAPHIC_EDGE *e1, const GEOGRAPHIC_EDGE *e2, GEOGRAPHIC_POINT *closest1, GEOGRAPHIC_POINT *closest2);
114 void geographic_point_init(double lon, double lat, GEOGRAPHIC_POINT *g);
115 int ptarray_contains_point_sphere(const POINTARRAY *pa, const POINT2D *pt_outside, const POINT2D *pt_to_test);
116 int lwpoly_covers_point2d(const LWPOLY *poly, const POINT2D *pt_to_test);
117 int lwpoly_covers_lwpoly(const LWPOLY *lwpoly1, const LWPOLY *lwpoly2);
118 int lwpoly_covers_pointarray(const LWPOLY* lwpoly, const POINTARRAY* pta);
119 int lwpoly_covers_lwline(const LWPOLY *poly, const LWLINE *line);
120 int lwline_covers_lwline(const LWLINE* lwline1, const LWLINE* lwline2);
121 int lwline_covers_lwpoint(const LWLINE* lwline, const LWPOINT* lwpoint);
122 int lwpoly_intersects_line(const LWPOLY* lwpoly, const POINTARRAY* line);
123 void lwpoly_pt_outside(const LWPOLY *poly, POINT2D *pt_outside);
124 int ptarray_point_in_ring(const POINTARRAY *pa, const POINT2D *pt_outside, const POINT2D *pt_to_test);
125 double ptarray_area_sphere(const POINTARRAY *pa);
126 double latitude_degrees_normalize(double lat);
127 double longitude_degrees_normalize(double lon);
128 double ptarray_length_spheroid(const POINTARRAY *pa, const SPHEROID *s);
131 void point_shift(GEOGRAPHIC_POINT *p, double shift);
132 double longitude_radians_normalize(double lon);
133 double latitude_radians_normalize(double lat);
134 void vector_sum(const POINT3D *a, const POINT3D *b, POINT3D *n);
135 double vector_angle(const POINT3D* v1, const POINT3D* v2);
136 void vector_rotate(const POINT3D* v1, const POINT3D* v2, double angle, POINT3D* n);
137 void normalize(POINT3D *p);
138 void unit_normal(const POINT3D *P1, const POINT3D *P2, POINT3D *normal);
139 double sphere_direction(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e, double d);
140 void ll2cart(const POINT2D *g, POINT3D *p);
141 
142 /*
143 ** Prototypes for spheroid functions.
144 */
145 double spheroid_distance(const GEOGRAPHIC_POINT *a, const GEOGRAPHIC_POINT *b, const SPHEROID *spheroid);
146 double spheroid_direction(const GEOGRAPHIC_POINT *r, const GEOGRAPHIC_POINT *s, const SPHEROID *spheroid);
147 int spheroid_project(const GEOGRAPHIC_POINT *r, const SPHEROID *spheroid, double distance, double azimuth, GEOGRAPHIC_POINT *g);
148 
149 
150 #endif /* _LWGEODETIC_H */
151 
152 
153 
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:917
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:603
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:1238
double longitude_radians_normalize(double lon)
Convert a longitude to the range of -PI,PI.
Definition: lwgeodetic.c:41
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:1283
Two-point great circle segment from a to b.
Definition: lwgeodetic.h:56
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:282
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:1003
void normalize(POINT3D *p)
Normalize to a unit vector.
Definition: lwgeodetic.c:584
int lwpoly_intersects_line(const LWPOLY *lwpoly, const POINTARRAY *line)
Checks if any edges of lwpoly intersect with the line formed by the pointarray return LW_TRUE if any ...
Definition: lwgeodetic.c:2628
int crosses_dateline(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e)
Definition: lwgeodetic.c:635
double z_to_latitude(double z, int top)
Used in great circle to compute the pole of the great circle.
Definition: lwgeodetic.c:1018
int lwpoly_covers_pointarray(const LWPOLY *lwpoly, const POINTARRAY *pta)
return LW_TRUE if all points are inside the polygon
Definition: lwgeodetic.c:2609
double measure
Definition: lwgeodetic.h:67
void cart2geog(const POINT3D *p, GEOGRAPHIC_POINT *g)
Convert cartesian coordinates on unit sphere to spherical coordinates.
Definition: lwgeodetic.c:383
int edge_calculate_gbox_slow(const GEOGRAPHIC_EDGE *e, GBOX *gbox)
Definition: lwgeodetic.c:1313
void point_shift(GEOGRAPHIC_POINT *p, double shift)
Shift a point around by a number of radians.
Definition: lwgeodetic.c:151
void y_to_z(POINT3D *p)
Definition: lwgeodetic.c:627
double longitude_degrees_normalize(double lon)
Convert a longitude to the range of -180,180.
Definition: lwgeodetic.c:97
Point in spherical coordinates on the world.
Definition: lwgeodetic.h:47
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:359
double latitude_degrees_normalize(double lat)
Convert a latitude to the range of -90,90.
Definition: lwgeodetic.c:124
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:1070
unsigned int uint32_t
Definition: uthash.h:78
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:510
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:3529
GEOGRAPHIC_POINT start
Definition: lwgeodetic.h:58
double edge_distance_to_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *gp, GEOGRAPHIC_POINT *closest)
Definition: lwgeodetic.c:1187
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:757
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:1045
uint32_t index
Definition: lwgeodetic.h:68
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:804
void x_to_z(POINT3D *p)
Definition: lwgeodetic.c:620
double ptarray_length_spheroid(const POINTARRAY *pa, const SPHEROID *s)
Definition: lwgeodetic.c:3156
void ll2cart(const POINT2D *g, POINT3D *p)
Convert lon/lat coordinates to cartesian coordinates on unit sphere.
Definition: lwgeodetic.c:392
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:542
int lwline_covers_lwline(const LWLINE *lwline1, const LWLINE *lwline2)
Check if first and last point of line2 are covered by line1 and then each point in between has to be ...
Definition: lwgeodetic.c:2699
int lwpoly_covers_lwline(const LWPOLY *poly, const LWLINE *line)
Definition: lwgeodetic.c:2573
void lwpoly_pt_outside(const LWPOLY *poly, POINT2D *pt_outside)
Definition: lwgeodetic.c:1444
int lwpoly_covers_lwpoly(const LWPOLY *lwpoly1, const LWPOLY *lwpoly2)
Given a polygon1 check if all points of polygon2 are inside polygon1 and no intersections of the poly...
Definition: lwgeodetic.c:2515
GEOGRAPHIC_POINT end
Definition: lwgeodetic.h:59
char * s
Definition: cu_in_wkt.c:23
uint32_t 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:3424
Datum distance(PG_FUNCTION_ARGS)
void geog2cart(const GEOGRAPHIC_POINT *g, POINT3D *p)
Convert spherical coordinates to cartesian coordinates on unit sphere.
Definition: lwgeodetic.c:373
int gbox_geocentric_slow
For testing geodetic bounding box, we have a magic global variable.
Definition: lwgeodetic.c:36
void vector_sum(const POINT3D *a, const POINT3D *b, POINT3D *n)
Calculate the sum of two vectors.
Definition: lwgeodetic.c:434
double latitude_radians_normalize(double lat)
Convert a latitude to the range of -PI/2,PI/2.
Definition: lwgeodetic.c:69
double sphere_distance_cartesian(const POINT3D *s, const POINT3D *e)
Given two unit vectors, calculate their distance apart in radians.
Definition: lwgeodetic.c:936
int geographic_point_equals(const GEOGRAPHIC_POINT *g1, const GEOGRAPHIC_POINT *g2)
Definition: lwgeodetic.c:161
Holder for sorting points in distance algorithm.
Definition: lwgeodetic.h:65
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:1720
void geographic_point_init(double lon, double lat, GEOGRAPHIC_POINT *g)
Initialize a geographic point.
Definition: lwgeodetic.c:171
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:186
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:2431
double vector_angle(const POINT3D *v1, const POINT3D *v2)
Angle between two unit vectors.
Definition: lwgeodetic.c:474
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:1377
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:744
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:1096
int lwline_covers_lwpoint(const LWLINE *lwline, const LWPOINT *lwpoint)
return LW_TRUE if any of the line segments covers the point
Definition: lwgeodetic.c:2670
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:944