ST_Intersects()

Datum ST_Intersects

(

PG_FUNCTION_ARGS

)

Definition at line 2188 of file postgis/lwgeom_geos.c.

{
        GSERIALIZED *geom1;
        GSERIALIZED *geom2;
        int result;
        GBOX box1, box2;
        PrepGeomCache *prep_cache;
 
        geom1 = PG_GETARG_GSERIALIZED_P(0);
        geom2 = PG_GETARG_GSERIALIZED_P(1);
        gserialized_error_if_srid_mismatch(geom1, geom2, __func__);
 
        /* A.Intersects(Empty) == FALSE */
        if ( gserialized_is_empty(geom1) || gserialized_is_empty(geom2) )
                PG_RETURN_BOOL(false);
 
        /*
         * short-circuit 1: if geom2 bounding box does not overlap
         * geom1 bounding box we can return FALSE.
         */
        if ( gserialized_get_gbox_p(geom1, &box1) &&
                gserialized_get_gbox_p(geom2, &box2) )
        {
                if ( gbox_overlaps_2d(&box1, &box2) == LW_FALSE )
                        PG_RETURN_BOOL(false);
        }
 
        /*
         * short-circuit 2: if the geoms are a point and a polygon,
         * call the point_outside_polygon function.
         */
        if ((is_point(geom1) && is_poly(geom2)) || (is_poly(geom1) && is_point(geom2)))
        {
                GSERIALIZED* gpoly  = is_poly(geom1) ? geom1 : geom2;
                GSERIALIZED* gpoint = is_point(geom1) ? geom1 : geom2;
                RTREE_POLY_CACHE* cache = GetRtreeCache(fcinfo, gpoly);
                int retval;
 
                POSTGIS_DEBUG(3, "Point in Polygon test requested...short-circuiting.");
                if (gserialized_get_type(gpoint) == POINTTYPE)
                {
                        LWGEOM* point = lwgeom_from_gserialized(gpoint);
                        int pip_result = pip_short_circuit(cache, lwgeom_as_lwpoint(point), gpoly);
                        lwgeom_free(point);
 
                        retval = (pip_result != -1); /* not outside */
                }
                else if (gserialized_get_type(gpoint) == MULTIPOINTTYPE)
                {
                        LWMPOINT* mpoint = lwgeom_as_lwmpoint(lwgeom_from_gserialized(gpoint));
                        uint32_t i;
 
                        retval = LW_FALSE;
                        for (i = 0; i < mpoint->ngeoms; i++)
                        {
                                int pip_result = pip_short_circuit(cache, mpoint->geoms[i], gpoly);
                                if (pip_result != -1) /* not outside */
                                {
                                        retval = LW_TRUE;
                                        break;
                                }
                        }
 
                        lwmpoint_free(mpoint);
                }
                else
                {
                        /* Never get here */
                        elog(ERROR,"Type isn't point or multipoint!");
                        PG_RETURN_NULL();
                }
 
                PG_FREE_IF_COPY(geom1, 0);
                PG_FREE_IF_COPY(geom2, 1);
                PG_RETURN_BOOL(retval);
        }
 
        initGEOS(lwpgnotice, lwgeom_geos_error);
        prep_cache = GetPrepGeomCache( fcinfo, geom1, geom2 );
 
        if ( prep_cache && prep_cache->prepared_geom )
        {
                if ( prep_cache->gcache.argnum == 1 )
                {
                        GEOSGeometry *g = POSTGIS2GEOS(geom2);
                        if (!g) HANDLE_GEOS_ERROR("Geometry could not be converted to GEOS");
                        result = GEOSPreparedIntersects( prep_cache->prepared_geom, g);
                        GEOSGeom_destroy(g);
                }
                else
                {
                        GEOSGeometry *g = POSTGIS2GEOS(geom1);
                        if (!g)
                                HANDLE_GEOS_ERROR("Geometry could not be converted to GEOS");
                        result = GEOSPreparedIntersects( prep_cache->prepared_geom, g);
                        GEOSGeom_destroy(g);
                }
        }
        else
        {
                GEOSGeometry *g1;
                GEOSGeometry *g2;
                g1 = POSTGIS2GEOS(geom1);
                if (!g1) HANDLE_GEOS_ERROR("First argument geometry could not be converted to GEOS");
                g2 = POSTGIS2GEOS(geom2);
                if (!g2)
                {
                        GEOSGeom_destroy(g1);
                        HANDLE_GEOS_ERROR("Second argument geometry could not be converted to GEOS");
                }
                result = GEOSIntersects( g1, g2);
                GEOSGeom_destroy(g1);
                GEOSGeom_destroy(g2);
        }
 
        if (result == 2) HANDLE_GEOS_ERROR("GEOSIntersects");
 
        PG_FREE_IF_COPY(geom1, 0);
        PG_FREE_IF_COPY(geom2, 1);
 
        PG_RETURN_BOOL(result);
}

References gbox_overlaps_2d(), PrepGeomCache::gcache, LWMPOINT::geoms, GetPrepGeomCache(), GetRtreeCache(), gserialized_error_if_srid_mismatch(), gserialized_get_gbox_p(), gserialized_get_type(), gserialized_is_empty(), HANDLE_GEOS_ERROR, is_point(), is_poly(), LW_FALSE, LW_TRUE, lwgeom_as_lwmpoint(), lwgeom_as_lwpoint(), lwgeom_free(), lwgeom_from_gserialized(), lwgeom_geos_error(), lwmpoint_free(), MULTIPOINTTYPE, LWMPOINT::ngeoms, pip_short_circuit(), POINTTYPE, POSTGIS2GEOS(), and PrepGeomCache::prepared_geom.

Here is the call graph for this function: