Datum LWGEOM_isclosed(PG_FUNCTION_ARGS)
{
GSERIALIZED *geom = (GSERIALIZED*)PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
LWGEOM *lwgeom = lwgeom_from_gserialized(geom);
int closed = lwgeom_is_closed(lwgeom);
lwgeom_free(lwgeom);
PG_FREE_IF_COPY(geom, 0);
PG_RETURN_BOOL(closed);
}
int
lwgeom_is_closed(const LWGEOM *geom)
{
int type = geom->type;
if( lwgeom_is_empty(geom) )
return LW_FALSE;
/* Test linear types for closure */
switch (type)
{
case LINETYPE:
return lwline_is_closed((LWLINE*)geom);
case POLYGONTYPE:
return lwpoly_is_closed((LWPOLY*)geom);
case CIRCSTRINGTYPE:
return lwcircstring_is_closed((LWCIRCSTRING*)geom);
case COMPOUNDTYPE:
return lwcompound_is_closed((LWCOMPOUND*)geom);
case TINTYPE:
return lwtin_is_closed((LWTIN*)geom);
case POLYHEDRALSURFACETYPE:
return lwpsurface_is_closed((LWPSURFACE*)geom);
}
/* Recurse into collections and see if anything is not closed */
if ( lwgeom_is_collection(geom) )
{
LWCOLLECTION *col = lwgeom_as_lwcollection(geom);
int i;
int closed;
for ( i = 0; i < col->ngeoms; i++ )
{
closed = lwgeom_is_closed(col->geoms[i]);
if ( ! closed )
return LW_FALSE;
}
return LW_TRUE;
}
/* All non-linear non-collection types we will call closed */
return LW_TRUE;
}
