self-hosted/postgis
self-hosted/postgis
1
0
Fork 0
mirror of https://git.osgeo.org/gitea/postgis/postgis synced 2024-10-24 09:02:37 +00:00
Code Issues Packages Projects Releases Wiki Activity

Have ST_Union aggregate use UnaryUnion from GEOS-3.0.0 (#922)

Browse source 
git-svn-id: http://svn.osgeo.org/postgis/trunk@9056 b70326c6-7e19-0410-871a-916f4a2858ee
This commit is contained in:
Paul Ramsey 2012-02-06 23:25:00 +00:00
parent 96720d5525
commit 3febad8085
2 changed files with 188 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

187
postgis/lwgeom_geos.c
View file

@ -250,7 +250,193 @@ Datum hausdorffdistancedensify(PG_FUNCTION_ARGS)
*/
PG_FUNCTION_INFO_V1(pgis_union_geometry_array);
Datum pgis_union_geometry_array(PG_FUNCTION_ARGS)
#if POSTGIS_GEOS_VERSION >= 33
{
/*
** For GEOS >= 3.3, use the new UnaryUnion functionality to merge the
** terminal collection from the ST_Union aggregate
*/
Datum datum;
ArrayType *array;
int is3d = LW_FALSE, gotsrid = LW_FALSE;
int nelems = 0, i = 0, geoms_size = 0, curgeom = 0;
GSERIALIZED *gser_out = NULL;
GEOSGeometry *g = NULL;
GEOSGeometry *g_union = NULL;
GEOSGeometry **geoms = NULL;
int srid = SRID_UNKNOWN;
size_t offset = 0;
bits8 *bitmap;
int bitmask;
int empty_type = 0;
datum = PG_GETARG_DATUM(0);
/* Null array, null geometry (should be empty?) */
if ( (Pointer *)datum == NULL ) PG_RETURN_NULL();
array = DatumGetArrayTypeP(datum);
/* How many things in our array? */
nelems = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
/* PgSQL supplies a bitmap of which array entries are null */
bitmap = ARR_NULLBITMAP(array);
/* Empty array? Null return */
if ( nelems == 0 ) PG_RETURN_NULL();
/* One-element union is the element itself! */
if ( nelems == 1 )
{
/* If the element is a NULL then we need to handle it separately */
if (bitmap && (*bitmap & 1) == 0)
PG_RETURN_NULL();
else
PG_RETURN_POINTER((GSERIALIZED *)(ARR_DATA_PTR(array)));
}
/* Ok, we really need GEOS now ;) */
initGEOS(lwnotice, lwgeom_geos_error);
/*
** Collect the non-empty inputs and stuff them into a GEOS collection
*/
geoms_size = nelems;
geoms = palloc( sizeof(GEOSGeometry*) * geoms_size );
/*
** We need to convert the array of GSERIALIZED into a GEOS collection.
** First make an array of GEOS geometries.
*/
offset = 0;
bitmap = ARR_NULLBITMAP(array);
bitmask = 1;
for ( i = 0; i < nelems; i++ )
{
/* Only work on non-NULL entries in the array */
if ((bitmap && (*bitmap & bitmask) != 0) || !bitmap)
{
GSERIALIZED *gser_in = (GSERIALIZED *)(ARR_DATA_PTR(array)+offset);
/* Check for SRID mismatch in array elements */
if ( gotsrid )
{
error_if_srid_mismatch(srid, gserialized_get_srid(gser_in));
}
else
{
/* Initialize SRID/dimensions info */
srid = gserialized_get_srid(gser_in);
is3d = gserialized_has_z(gser_in);
gotsrid = 1;
}
/* Don't include empties in the union */
if ( gserialized_is_empty(gser_in) )
{
int gser_type = gserialized_get_type(gser_in);
if (gser_type > empty_type)
{
empty_type = gser_type;
}
}
else
{
g = (GEOSGeometry *)POSTGIS2GEOS(gser_in);
/* Uh oh! Exception thrown at construction... */
if ( ! g )
{
lwerror("One of the geometries in the set "
"could not be converted to GEOS: %s", lwgeom_geos_errmsg);
PG_RETURN_NULL();
}
/* Ensure we have enough space in our storage array */
if ( curgeom == geoms_size )
{
geoms_size *= 2;
geoms = repalloc( geoms, sizeof(GEOSGeometry*) * geoms_size );
}
offset += INTALIGN(VARSIZE(gser_in));
geoms[curgeom] = g;
curgeom++;
}
}
/* Advance NULL bitmap */
if (bitmap)
{
bitmask <<= 1;
if (bitmask == 0x100)
{
bitmap++;
bitmask = 1;
}
}
}
/*
** Take our GEOS geometries and turn them into a GEOS collection,
** then pass that into cascaded union.
*/
if (curgeom > 0)
{
g = GEOSGeom_createCollection(GEOS_GEOMETRYCOLLECTION, geoms, curgeom);
if ( ! g )
{
lwerror("Could not create GEOS COLLECTION from geometry array: %s", lwgeom_geos_errmsg);
PG_RETURN_NULL();
}
g_union = GEOSUnaryUnion(g);
GEOSGeom_destroy(g);
if ( ! g_union )
{
lwerror("GEOSUnaryUnion: %s",
lwgeom_geos_errmsg);
PG_RETURN_NULL();
}
GEOSSetSRID(g_union, srid);
gser_out = GEOS2POSTGIS(g_union, is3d);
GEOSGeom_destroy(g_union);
}
/* No real geometries in our array, any empties? */
else
{
/* If it was only empties, we'll return the largest type number */
if ( empty_type > 0 )
{
PG_RETURN_POINTER(geometry_serialize(lwgeom_construct_empty(empty_type, srid, is3d, 0)));
}
/* Nothing but NULL, returns NULL */
else
{
PG_RETURN_NULL();
}
}
if ( ! gser_out )
{
/* Union returned a NULL geometry */
PG_RETURN_NULL();
}
PG_RETURN_POINTER(gser_out);
}
#else
{
/* For GEOS < 3.3, use the old CascadedUnion function for polygons and
brute force two-by-two for other types. */
Datum datum;
ArrayType *array;
int is3d = 0;
@ -564,6 +750,7 @@ Datum pgis_union_geometry_array(PG_FUNCTION_ARGS)
PG_RETURN_POINTER(result);
}
#endif /* POSTGIS_GEOS_VERSION >= 33 */
/**
* @example ST_UnaryUnion {@link #geomunion} SELECT ST_UnaryUnion(

2
topology/test/regress/legacy_query_expected
View file

@ -41,7 +41,7 @@ E20E19|6|MULTILINESTRING((21 6,21 14,21 22))
E25|7|MULTILINESTRING((9 35,13 35))
R1a|8|MULTILINESTRING((9 14,21 14,35 14))
S1S2|MULTIPOINT(21 14,35 14)
R1R2|MULTILINESTRING((36 38,38 35,41 34,42 33,45 32,47 28,50 28,52 32,57 33,57 36,59 39,61 38,62 41,47 42,45 40,41 40),(9 14,21 14,35 14))
R1R2|MULTILINESTRING((9 14,21 14,35 14),(36 38,38 35,41 34,42 33,45 32,47 28,50 28,52 32,57 33,57 36,59 39,61 38,62 41,47 42,45 40,41 40))
R4|MULTILINESTRING((25 30,25 35))
P1P2|MULTIPOLYGON(((21 6,9 6,9 14,9 22,21 22,35 22,35 14,35 6,21 6)))
P3P4|MULTIPOLYGON(((47 14,47 6,35 6,35 14,35 22,47 22,47 14)),((25 30,17 30,17 40,31 40,31 30,25 30)))