PostGIS  2.5.0beta2dev-r@@SVN_REVISION@@

◆ lwgeom_union()

LWGEOM* lwgeom_union ( const LWGEOM geom1,
const LWGEOM geom2 
)

Definition at line 896 of file liblwgeom/lwgeom_geos.c.

References AUTOFIX, LWGEOM::flags, FLAGS_GET_Z, GEOS2LWGEOM(), GEOS_FAIL, GEOS_FREE, GEOS_FREE_AND_FAIL, LWGEOM2GEOS(), lwgeom_clone_deep(), lwgeom_geos_errmsg, lwgeom_geos_error(), LWGEOM_GEOS_makeValid(), lwgeom_is_empty(), lwnotice(), RESULT_SRID, and SRID_INVALID.

Referenced by _lwt_AddLine(), and geos_geomunion().

897 {
898  LWGEOM* result;
899  int32_t srid = RESULT_SRID(geom1, geom2);
900  uint8_t is3d = (FLAGS_GET_Z(geom1->flags) || FLAGS_GET_Z(geom2->flags));
901  GEOSGeometry *g1, *g2, *g3;
902 
903  if (srid == SRID_INVALID) return NULL;
904 
905  /* A.Union(empty) == A */
906  if (lwgeom_is_empty(geom1)) return lwgeom_clone_deep(geom2);
907 
908  /* B.Union(empty) == B */
909  if (lwgeom_is_empty(geom2)) return lwgeom_clone_deep(geom1);
910 
911  initGEOS(lwnotice, lwgeom_geos_error);
912 
913  if (!(g1 = LWGEOM2GEOS(geom1, AUTOFIX))) GEOS_FAIL();
914  if (!(g2 = LWGEOM2GEOS(geom2, AUTOFIX))) GEOS_FREE_AND_FAIL(g1);
915 
916  g3 = GEOSUnion(g1, g2);
917 
918  if (!g3)
919  {
920  GEOSGeometry *g1v, *g2v;
921  lwnotice("%s: GEOS Error: %s", __func__, lwgeom_geos_errmsg);
922 
923  if (!GEOSisValid(g1) || !GEOSisValid(g2))
924  {
925  lwnotice(
926  "Your geometry dataset is not valid per OGC Specification. "
927  "Please fix it with manual review of entries that are not ST_IsValid(geom). "
928  "Retrying GEOS operation with ST_MakeValid of your input.");
929  g1v = LWGEOM_GEOS_makeValid(g1);
930  g2v = LWGEOM_GEOS_makeValid(g2);
931  g3 = GEOSUnion(g1v, g2v);
932  GEOS_FREE(g1v, g2v);
933  }
934  }
935 
936  if (!g3) GEOS_FREE_AND_FAIL(g1, g2);
937  GEOSSetSRID(g3, srid);
938 
939  if (!(result = GEOS2LWGEOM(g3, is3d)))
940  GEOS_FREE_AND_FAIL(g1, g2, g3);
941 
942  GEOS_FREE(g1, g2, g3);
943  return result;
944 }
#define GEOS_FAIL()
LWGEOM * GEOS2LWGEOM(const GEOSGeometry *geom, uint8_t want3d)
void lwnotice(const char *fmt,...)
Write a notice out to the notice handler.
Definition: lwutil.c:177
uint8_t flags
Definition: liblwgeom.h:399
GEOSGeometry * LWGEOM_GEOS_makeValid(const GEOSGeometry *)
char lwgeom_geos_errmsg[LWGEOM_GEOS_ERRMSG_MAXSIZE]
#define GEOS_FREE_AND_FAIL(...)
#define GEOS_FREE(...)
LWGEOM * lwgeom_clone_deep(const LWGEOM *lwgeom)
Deep clone an LWGEOM, everything is copied.
Definition: lwgeom.c:520
#define RESULT_SRID(...)
#define AUTOFIX
void lwgeom_geos_error(const char *fmt,...)
#define SRID_INVALID
Definition: liblwgeom.h:191
#define FLAGS_GET_Z(flags)
Macros for manipulating the 'flags' byte.
Definition: liblwgeom.h:139
GEOSGeometry * LWGEOM2GEOS(const LWGEOM *lwgeom, uint8_t autofix)
int lwgeom_is_empty(const LWGEOM *geom)
Return true or false depending on whether a geometry is an "empty" geometry (no vertices members) ...
Definition: lwgeom.c:1393
unsigned char uint8_t
Definition: uthash.h:79
Here is the call graph for this function:
Here is the caller graph for this function: