Datum BOX2D_construct(PG_FUNCTION_ARGS)
{
GSERIALIZED *pgmin = (GSERIALIZED *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
GSERIALIZED *pgmax = (GSERIALIZED *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
GBOX *result;
LWPOINT *minpoint, *maxpoint;
double min, max, tmp;
minpoint = (LWPOINT*)lwgeom_from_gserialized(pgmin);
maxpoint = (LWPOINT*)lwgeom_from_gserialized(pgmax);
if ( (minpoint->type != POINTTYPE) || (maxpoint->type != POINTTYPE) )
{
elog(ERROR, "GBOX_construct: arguments must be points");
PG_RETURN_NULL();
}
error_if_srid_mismatch(minpoint->srid, maxpoint->srid);
result = gbox_new(gflags(0, 0, 0));
/* Process X min/max */
min = lwpoint_get_x(minpoint);
max = lwpoint_get_x(maxpoint);
if ( min > max )
{
tmp = min;
min = max;
max = tmp;
}
result->xmin = min;
result->xmax = max;
/* Process Y min/max */
min = lwpoint_get_y(minpoint);
max = lwpoint_get_y(maxpoint);
if ( min > max )
{
tmp = min;
min = max;
max = tmp;
}
result->ymin = min;
result->ymax = max;
PG_RETURN_POINTER(result);
}
Datum
spgist_geom_picksplit(PG_FUNCTION_ARGS)
{
spgPickSplitIn *in = (spgPickSplitIn *) PG_GETARG_POINTER(0);
spgPickSplitOut *out = (spgPickSplitOut *) PG_GETARG_POINTER(1);
int i;
double x, y;
BOX2DF *centroidbox_p;
/* Use the average values of x and y as the centroid point */
x = 0;
y = 0;
for (i = 0; i < in->nTuples; i++)
{
LWPOINT *apt = (LWPOINT *)lwgeom_from_gserialized((GSERIALIZED *)in->datums[i]);
x += lwpoint_get_x(apt);
y += lwpoint_get_y(apt);
lwpoint_free(apt);
}
x /= in->nTuples;
y /= in->nTuples;
centroidbox_p = palloc(sizeof(BOX2DF));
centroidbox_p->xmin = x;
centroidbox_p->xmax = x;
centroidbox_p->ymin = y;
centroidbox_p->ymax = y;
out->hasPrefix = true;
out->prefixDatum = PointerGetDatum(centroidbox_p);
out->nNodes = 4;
out->nodeLabels = NULL; /* we don't need node labels */
out->mapTuplesToNodes = palloc(sizeof(int) * in->nTuples);
out->leafTupleDatums = palloc(sizeof(Datum) * in->nTuples);
for (i = 0; i < in->nTuples; i++)
{
BOX2DF box;
gserialized_datum_get_box2df_p(in->datums[i], &box);
int quadrant = getQuadrant(centroidbox_p, &box) - 1;
out->leafTupleDatums[i] = PointerGetDatum(in->datums[i]);
out->mapTuplesToNodes[i] = quadrant;
}
PG_RETURN_VOID();
}
