PostGIS  3.0.6dev-r@@SVN_REVISION@@

◆ geography_distance_uncached()

Datum geography_distance_uncached ( PG_FUNCTION_ARGS  )

Definition at line 134 of file geography_measurement.c.

135 {
136  LWGEOM *lwgeom1 = NULL;
137  LWGEOM *lwgeom2 = NULL;
138  GSERIALIZED *g1 = NULL;
139  GSERIALIZED *g2 = NULL;
140  double distance;
141  double tolerance = FP_TOLERANCE;
142  bool use_spheroid = true;
143  SPHEROID s;
144 
145  /* Get our geometry objects loaded into memory. */
146  g1 = PG_GETARG_GSERIALIZED_P(0);
147  g2 = PG_GETARG_GSERIALIZED_P(1);
148 
149  /* Read our tolerance value. */
150  if ( PG_NARGS() > 2 && ! PG_ARGISNULL(2) )
151  tolerance = PG_GETARG_FLOAT8(2);
152 
153  /* Read our calculation type. */
154  if ( PG_NARGS() > 3 && ! PG_ARGISNULL(3) )
155  use_spheroid = PG_GETARG_BOOL(3);
156 
157  gserialized_error_if_srid_mismatch(g1, g2, __func__);
158 
159  /* Initialize spheroid */
160  spheroid_init_from_srid(fcinfo, gserialized_get_srid(g1), &s);
161 
162  /* Set to sphere if requested */
163  if ( ! use_spheroid )
164  s.a = s.b = s.radius;
165 
166  lwgeom1 = lwgeom_from_gserialized(g1);
167  lwgeom2 = lwgeom_from_gserialized(g2);
168 
169  /* Return NULL on empty arguments. */
170  if ( lwgeom_is_empty(lwgeom1) || lwgeom_is_empty(lwgeom2) )
171  {
172  PG_FREE_IF_COPY(g1, 0);
173  PG_FREE_IF_COPY(g2, 1);
174  PG_RETURN_NULL();
175  }
176 
177  /* Make sure we have boxes attached */
178  lwgeom_add_bbox_deep(lwgeom1, NULL);
179  lwgeom_add_bbox_deep(lwgeom2, NULL);
180 
181  distance = lwgeom_distance_spheroid(lwgeom1, lwgeom2, &s, tolerance);
182 
183  POSTGIS_DEBUGF(2, "[GIST] '%s' got distance %g", __func__, distance);
184 
185  /* Clean up */
186  lwgeom_free(lwgeom1);
187  lwgeom_free(lwgeom2);
188  PG_FREE_IF_COPY(g1, 0);
189  PG_FREE_IF_COPY(g2, 1);
190 
191  /* Something went wrong, negative return... should already be eloged, return NULL */
192  if ( distance < 0.0 )
193  {
194  PG_RETURN_NULL();
195  }
196 
197  PG_RETURN_FLOAT8(distance);
198 }
char * s
Definition: cu_in_wkt.c:23
void gserialized_error_if_srid_mismatch(const GSERIALIZED *g1, const GSERIALIZED *g2, const char *funcname)
Definition: gserialized.c:404
int32_t gserialized_get_srid(const GSERIALIZED *g)
Extract the SRID from the serialized form (it is packed into three bytes so this is a handy function)...
Definition: gserialized.c:126
LWGEOM * lwgeom_from_gserialized(const GSERIALIZED *g)
Allocate a new LWGEOM from a GSERIALIZED.
Definition: gserialized.c:239
double lwgeom_distance_spheroid(const LWGEOM *lwgeom1, const LWGEOM *lwgeom2, const SPHEROID *spheroid, double tolerance)
Calculate the geodetic distance from lwgeom1 to lwgeom2 on the spheroid.
Definition: lwgeodetic.c:2187
void lwgeom_free(LWGEOM *geom)
Definition: lwgeom.c:1138
void lwgeom_add_bbox_deep(LWGEOM *lwgeom, GBOX *gbox)
Compute a box for geom and all sub-geometries, if not already computed.
Definition: lwgeom.c:696
#define FP_TOLERANCE
Floating point comparators.
static int lwgeom_is_empty(const LWGEOM *geom)
Return true or false depending on whether a geometry is an "empty" geometry (no vertices members)
Definition: lwinline.h:193
static double distance(double x1, double y1, double x2, double y2)
Definition: lwtree.c:1032

References distance(), FP_TOLERANCE, gserialized_error_if_srid_mismatch(), gserialized_get_srid(), lwgeom_add_bbox_deep(), lwgeom_distance_spheroid(), lwgeom_free(), lwgeom_from_gserialized(), lwgeom_is_empty(), and s.

Here is the call graph for this function: