PostGIS  3.7.0dev-r@@SVN_REVISION@@

◆ geography_line_locate_point()

Datum geography_line_locate_point ( PG_FUNCTION_ARGS  )

Definition at line 1346 of file geography_measurement.c.

1347 {
1348  GSERIALIZED *gs1 = PG_GETARG_GSERIALIZED_P(0);
1349  GSERIALIZED *gs2 = PG_GETARG_GSERIALIZED_P(1);
1350  bool use_spheroid = PG_GETARG_BOOL(2);
1351  double tolerance = FP_TOLERANCE;
1352  SPHEROID s;
1353  LWLINE *lwline;
1354  LWPOINT *lwpoint;
1355  POINTARRAY *pa;
1356  POINT4D p, p_proj;
1357  double ret;
1358 
1359  gserialized_error_if_srid_mismatch(gs1, gs2, __func__);
1360 
1361  /* Return NULL on empty argument. */
1362  if ( gserialized_is_empty(gs1) || gserialized_is_empty(gs2))
1363  {
1364  PG_FREE_IF_COPY(gs1, 0);
1365  PG_FREE_IF_COPY(gs2, 1);
1366  PG_RETURN_NULL();
1367  }
1368 
1369  if ( gserialized_get_type(gs1) != LINETYPE )
1370  {
1371  elog(ERROR,"%s: 1st arg is not a line", __func__);
1372  PG_RETURN_NULL();
1373  }
1374  if ( gserialized_get_type(gs2) != POINTTYPE )
1375  {
1376  elog(ERROR,"%s: 2nd arg is not a point", __func__);
1377  PG_RETURN_NULL();
1378  }
1379 
1380  /* Set to sphere if requested */
1381  if ( ! use_spheroid ) {
1382  s.a = s.b = s.radius;
1383  }
1384  else {
1385  /* Initialize spheroid */
1386  spheroid_init_from_srid(gserialized_get_srid(gs1), &s);
1387  }
1388 
1391 
1392  pa = lwline->points;
1393  lwpoint_getPoint4d_p(lwpoint, &p);
1394 
1395  ret = ptarray_locate_point_spheroid(pa, &p, &s, tolerance, NULL, &p_proj);
1396 
1397  PG_RETURN_FLOAT8(ret);
1398 }
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:432
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:155
LWGEOM * lwgeom_from_gserialized(const GSERIALIZED *g)
Allocate a new LWGEOM from a GSERIALIZED.
Definition: gserialized.c:268
int gserialized_is_empty(const GSERIALIZED *g)
Check if a GSERIALIZED is empty without deserializing first.
Definition: gserialized.c:181
uint32_t gserialized_get_type(const GSERIALIZED *g)
Extract the geometry type from the serialized form (it hides in the anonymous data area,...
Definition: gserialized.c:118
int lwpoint_getPoint4d_p(const LWPOINT *point, POINT4D *out)
Definition: lwpoint.c:57
LWLINE * lwgeom_as_lwline(const LWGEOM *lwgeom)
Definition: lwgeom.c:179
double ptarray_locate_point_spheroid(const POINTARRAY *pa, const POINT4D *p4d, const SPHEROID *s, double tolerance, double *mindistout, POINT4D *proj4d)
Locate a point along the point array defining a geographic line.
#define LINETYPE
Definition: liblwgeom.h:103
#define POINTTYPE
LWTYPE numbers, used internally by PostGIS.
Definition: liblwgeom.h:102
#define FP_TOLERANCE
Floating point comparators.
static LWPOINT * lwgeom_as_lwpoint(const LWGEOM *lwgeom)
Definition: lwinline.h:127
POINTARRAY * points
Definition: liblwgeom.h:483

References FP_TOLERANCE, gserialized_error_if_srid_mismatch(), gserialized_get_srid(), gserialized_get_type(), gserialized_is_empty(), LINETYPE, lwgeom_as_lwline(), lwgeom_as_lwpoint(), lwgeom_from_gserialized(), lwpoint_getPoint4d_p(), LWLINE::points, POINTTYPE, ptarray_locate_point_spheroid(), and s.

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