boundary()

Datum boundary

(

PG_FUNCTION_ARGS

)

Definition at line 835 of file postgis/lwgeom_geos.c.

{
        GSERIALIZED     *geom1;
        GEOSGeometry *g1, *g3;
        GSERIALIZED *result;
        LWGEOM *lwgeom;
        int32_t srid;
 
        geom1 = PG_GETARG_GSERIALIZED_P(0);
 
        /* Empty.Boundary() == Empty */
        if ( gserialized_is_empty(geom1) )
                PG_RETURN_POINTER(geom1);
 
        srid = gserialized_get_srid(geom1);
 
        lwgeom = lwgeom_from_gserialized(geom1);
        if ( ! lwgeom ) {
                lwpgerror("POSTGIS2GEOS: unable to deserialize input");
                PG_RETURN_NULL();
        }
 
        /* GEOS doesn't do triangle type, so we special case that here */
        if (lwgeom->type == TRIANGLETYPE)
        {
                lwgeom->type = LINETYPE;
                result = geometry_serialize(lwgeom);
                lwgeom_free(lwgeom);
                PG_RETURN_POINTER(result);
        }
 
        initGEOS(lwpgnotice, lwgeom_geos_error);
 
        g1 = LWGEOM2GEOS(lwgeom, 0);
        lwgeom_free(lwgeom);
 
        if (!g1)
                HANDLE_GEOS_ERROR("First argument geometry could not be converted to GEOS");
 
        g3 = GEOSBoundary(g1);
 
        if (!g3)
        {
                GEOSGeom_destroy(g1);
                HANDLE_GEOS_ERROR("GEOSBoundary");
        }
 
        POSTGIS_DEBUGF(3, "result: %s", GEOSGeomToWKT(g3));
 
        GEOSSetSRID(g3, srid);
 
        result = GEOS2POSTGIS(g3, gserialized_has_z(geom1));
 
        if (!result)
        {
                GEOSGeom_destroy(g1);
                GEOSGeom_destroy(g3);
                elog(NOTICE,
                     "GEOS2POSTGIS threw an error (result postgis geometry "
                     "formation)!");
                PG_RETURN_NULL(); /* never get here */
        }
 
        GEOSGeom_destroy(g1);
        GEOSGeom_destroy(g3);
 
        PG_FREE_IF_COPY(geom1, 0);
 
        PG_RETURN_POINTER(result);
}

References GEOS2POSTGIS(), gserialized_get_srid(), gserialized_has_z(), gserialized_is_empty(), HANDLE_GEOS_ERROR, LINETYPE, LWGEOM2GEOS(), lwgeom_free(), lwgeom_from_gserialized(), lwgeom_geos_error(), result, TRIANGLETYPE, and LWGEOM::type.

Here is the call graph for this function: