Datum LWGEOM_from_WKB(PG_FUNCTION_ARGS)
{
GSERIALIZED *geom;
int32 srid;
GSERIALIZED *result = NULL;
geom = (GSERIALIZED *)DatumGetPointer(DirectFunctionCall1(
LWGEOMFromWKB, PG_GETARG_DATUM(0)));
if ( gserialized_get_srid(geom) != SRID_UNKNOWN )
{
elog(WARNING, "OGC WKB expected, EWKB provided - use GeometryFromEWKB() for this");
}
/* read user-requested SRID if any */
if ( PG_NARGS() > 1 )
{
srid = PG_GETARG_INT32(1);
if ( srid != gserialized_get_srid(geom) )
gserialized_set_srid(geom, srid);
}
if ( ! result ) result = geom;
PG_RETURN_POINTER(result);
}
Datum LWGEOM_set_srid(PG_FUNCTION_ARGS)
{
GSERIALIZED *g = (GSERIALIZED *)PG_DETOAST_DATUM_COPY(PG_GETARG_DATUM(0));
int srid = PG_GETARG_INT32(1);
gserialized_set_srid(g, srid);
PG_RETURN_POINTER(g);
}
Datum LWGEOM_from_WKB(PG_FUNCTION_ARGS)
{
bytea *bytea_wkb = (bytea*)PG_GETARG_BYTEA_P(0);
int32 srid = 0;
GSERIALIZED *geom;
LWGEOM *lwgeom;
uint8_t *wkb = (uint8_t*)VARDATA(bytea_wkb);
lwgeom = lwgeom_from_wkb(wkb, VARSIZE(bytea_wkb)-VARHDRSZ, LW_PARSER_CHECK_ALL);
if ( lwgeom_needs_bbox(lwgeom) )
lwgeom_add_bbox(lwgeom);
geom = geometry_serialize(lwgeom);
lwgeom_free(lwgeom);
PG_FREE_IF_COPY(bytea_wkb, 0);
if ( gserialized_get_srid(geom) != SRID_UNKNOWN )
{
elog(WARNING, "OGC WKB expected, EWKB provided - use GeometryFromEWKB() for this");
}
if ( PG_NARGS() > 1 )
{
srid = PG_GETARG_INT32(1);
if ( srid != gserialized_get_srid(geom) )
gserialized_set_srid(geom, srid);
}
PG_RETURN_POINTER(geom);
}
GSERIALIZED* gserialized_from_lwgeom(LWGEOM *geom, int is_geodetic, size_t *size)
{
size_t expected_size = 0;
size_t return_size = 0;
uint8_t *serialized = NULL;
uint8_t *ptr = NULL;
GSERIALIZED *g = NULL;
assert(geom);
/*
** See if we need a bounding box, add one if we don't have one.
*/
if ( (! geom->bbox) && lwgeom_needs_bbox(geom) && (!lwgeom_is_empty(geom)) )
{
lwgeom_add_bbox(geom);
}
/*
** Harmonize the flags to the state of the lwgeom
*/
if ( geom->bbox )
FLAGS_SET_BBOX(geom->flags, 1);
/* Set up the uint8_t buffer into which we are going to write the serialized geometry. */
expected_size = gserialized_from_lwgeom_size(geom);
serialized = lwalloc(expected_size);
ptr = serialized;
/* Move past size, srid and flags. */
ptr += 8;
/* Write in the serialized form of the gbox, if necessary. */
if ( geom->bbox )
ptr += gserialized_from_gbox(geom->bbox, ptr);
/* Write in the serialized form of the geometry. */
ptr += gserialized_from_lwgeom_any(geom, ptr);
/* Calculate size as returned by data processing functions. */
return_size = ptr - serialized;
if ( expected_size != return_size ) /* Uh oh! */
{
lwerror("Return size (%d) not equal to expected size (%d)!", return_size, expected_size);
return NULL;
}
if ( size ) /* Return the output size to the caller if necessary. */
*size = return_size;
g = (GSERIALIZED*)serialized;
/*
** We are aping PgSQL code here, PostGIS code should use
** VARSIZE to set this for real.
*/
g->size = return_size << 2;
/* Set the SRID! */
gserialized_set_srid(g, geom->srid);
g->flags = geom->flags;
return g;
}
Datum BOX3D_to_LWGEOM(PG_FUNCTION_ARGS)
{
BOX3D *box = (BOX3D *)PG_GETARG_POINTER(0);
POINTARRAY *pa;
GSERIALIZED *result;
POINT4D pt;
/**
* Alter BOX3D cast so that a valid geometry is always
* returned depending upon the size of the BOX3D. The
* code makes the following assumptions:
* - If the BOX3D is a single point then return a
* POINT geometry
* - If the BOX3D represents either a horizontal or
* vertical line, return a LINESTRING geometry
* - Otherwise return a POLYGON
*/
pa = ptarray_construct_empty(0, 0, 5);
if ( (box->xmin == box->xmax) && (box->ymin == box->ymax) )
{
LWPOINT *lwpt = lwpoint_construct(SRID_UNKNOWN, NULL, pa);
pt.x = box->xmin;
pt.y = box->ymin;
ptarray_append_point(pa, &pt, LW_TRUE);
result = geometry_serialize(lwpoint_as_lwgeom(lwpt));
}
else if (box->xmin == box->xmax ||
box->ymin == box->ymax)
{
LWLINE *lwline = lwline_construct(SRID_UNKNOWN, NULL, pa);
pt.x = box->xmin;
pt.y = box->ymin;
ptarray_append_point(pa, &pt, LW_TRUE);
pt.x = box->xmax;
pt.y = box->ymax;
ptarray_append_point(pa, &pt, LW_TRUE);
result = geometry_serialize(lwline_as_lwgeom(lwline));
}
else
{
LWPOLY *lwpoly = lwpoly_construct(SRID_UNKNOWN, NULL, 1, &pa);
pt.x = box->xmin;
pt.y = box->ymin;
ptarray_append_point(pa, &pt, LW_TRUE);
pt.x = box->xmin;
pt.y = box->ymax;
ptarray_append_point(pa, &pt, LW_TRUE);
pt.x = box->xmax;
pt.y = box->ymax;
ptarray_append_point(pa, &pt, LW_TRUE);
pt.x = box->xmax;
pt.y = box->ymin;
ptarray_append_point(pa, &pt, LW_TRUE);
pt.x = box->xmin;
pt.y = box->ymin;
ptarray_append_point(pa, &pt, LW_TRUE);
result = geometry_serialize(lwpoly_as_lwgeom(lwpoly));
}
gserialized_set_srid(result, box->srid);
PG_RETURN_POINTER(result);
}
