char *msudf_pointOnSurface(UDF_INIT *initid,UDF_ARGS *args, char *buf,
unsigned long *length, char *is_null, char *error)
{
char *result;
GEOSGeom geom1,geom2;
DEBUG("msudf_pointOnSurface");
geom1 = msudf_getGeometry((unsigned char *)args->args[0],args->lengths[0]);
if (geom1 == NULL) {
strcpy(error,"Invalid geometry.");
*is_null = 1;
return NULL;
}
geom2 = GEOSPointOnSurface(geom1);
if (geom2 != NULL) {
GEOSSetSRID(geom2,GEOSGetSRID(geom1));
result = msudf_returnGeometry(initid,length,geom2);
GEOSGeom_destroy(geom1);
GEOSGeom_destroy(geom2);
return result;
} else {
GEOSGeom_destroy(geom1);
*is_null = 1;
return NULL;
}
}
int OGRPolygon::PointOnSurface( OGRPoint *poPoint ) const
{
if( poPoint == NULL )
return OGRERR_FAILURE;
#ifndef HAVE_GEOS
return OGRERR_FAILURE;
#else
GEOSGeom hThisGeosGeom = NULL;
GEOSGeom hOtherGeosGeom = NULL;
hThisGeosGeom = exportToGEOS();
if( hThisGeosGeom != NULL )
{
hOtherGeosGeom = GEOSPointOnSurface( hThisGeosGeom );
GEOSGeom_destroy( hThisGeosGeom );
if( hOtherGeosGeom == NULL )
return OGRERR_FAILURE;
OGRGeometry *poInsidePointGeom = (OGRGeometry *)
OGRGeometryFactory::createFromGEOS( hOtherGeosGeom );
GEOSGeom_destroy( hOtherGeosGeom );
if (poInsidePointGeom == NULL)
return OGRERR_FAILURE;
if (wkbFlatten(poInsidePointGeom->getGeometryType()) != wkbPoint)
{
delete poInsidePointGeom;
return OGRERR_FAILURE;
}
OGRPoint *poInsidePoint = (OGRPoint *) poInsidePointGeom;
poPoint->setX( poInsidePoint->getX() );
poPoint->setY( poInsidePoint->getY() );
delete poInsidePointGeom;
return OGRERR_NONE;
}
else
{
return OGRERR_FAILURE;
}
#endif /* HAVE_GEOS */
}
void object::test<2>()
{
geom1_ = GEOSGeomFromWKT("LINESTRING(0 0, 5 0, 10 0)");
ensure( 0 != geom1_ );
geom2_ = GEOSPointOnSurface(geom1_);
ensure( 0 != geom2_ );
wkt_ = GEOSWKTWriter_write(wktw_, geom2_);
ensure_equals(std::string(wkt_), std::string( "POINT (5 0)"));
}
void object::test<3>()
{
geom1_ = GEOSGeomFromWKT("POLYGON((0 0, 10 0, 10 10, 0 10, 0 0))");
ensure( 0 != geom1_ );
geom2_ = GEOSPointOnSurface(geom1_);
ensure( 0 != geom2_ );
wkt_ = GEOSWKTWriter_write(wktw_, geom2_);
ensure_equals(std::string(wkt_), std::string( "POINT (5 5)"));
}
/* Initializes and uses GEOS internally */
static LWGEOM*
lwpoly_split_by_line(const LWPOLY* lwpoly_in, const LWLINE* blade_in)
{
LWCOLLECTION* out;
GEOSGeometry* g1;
GEOSGeometry* g2;
GEOSGeometry* g1_bounds;
GEOSGeometry* polygons;
const GEOSGeometry *vgeoms[1];
int i,n;
int hasZ = FLAGS_GET_Z(lwpoly_in->flags);
/* Possible outcomes:
*
* 1. The line does not split the polygon
* -> Return a collection with single element
* 2. The line does split the polygon
* -> Return a collection of all elements resulting from the split
*/
initGEOS(lwgeom_geos_error, lwgeom_geos_error);
g1 = LWGEOM2GEOS((LWGEOM*)lwpoly_in, 0);
if ( NULL == g1 )
{
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
g1_bounds = GEOSBoundary(g1);
if ( NULL == g1_bounds )
{
GEOSGeom_destroy(g1);
lwerror("GEOSBoundary: %s", lwgeom_geos_errmsg);
return NULL;
}
g2 = LWGEOM2GEOS((LWGEOM*)blade_in, 0);
if ( NULL == g2 )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g1_bounds);
lwerror("LWGEOM2GEOS: %s", lwgeom_geos_errmsg);
return NULL;
}
vgeoms[0] = GEOSUnion(g1_bounds, g2);
if ( NULL == vgeoms[0] )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
lwerror("GEOSUnion: %s", lwgeom_geos_errmsg);
return NULL;
}
polygons = GEOSPolygonize(vgeoms, 1);
if ( NULL == polygons )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
lwerror("GEOSPolygonize: %s", lwgeom_geos_errmsg);
return NULL;
}
#if PARANOIA_LEVEL > 0
if ( GEOSGeomTypeId(polygons) != COLLECTIONTYPE )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
lwerror("%s [%s] Unexpected return from GEOSpolygonize", __FILE__, __LINE__);
return 0;
}
#endif
/* We should now have all polygons, just skip
* the ones which are in holes of the original
* geometries and return the rest in a collection
*/
n = GEOSGetNumGeometries(polygons);
out = lwcollection_construct_empty(COLLECTIONTYPE, lwpoly_in->srid,
hasZ, 0);
/* Allocate space for all polys */
out->geoms = lwrealloc(out->geoms, sizeof(LWGEOM*)*n);
assert(0 == out->ngeoms);
for (i=0; i<n; ++i)
{
GEOSGeometry* pos; /* point on surface */
const GEOSGeometry* p = GEOSGetGeometryN(polygons, i);
int contains;
pos = GEOSPointOnSurface(p);
if ( ! pos )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
lwerror("GEOSPointOnSurface: %s", lwgeom_geos_errmsg);
return NULL;
}
contains = GEOSContains(g1, pos);
if ( 2 == contains )
{
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
GEOSGeom_destroy(pos);
lwerror("GEOSContains: %s", lwgeom_geos_errmsg);
return NULL;
}
GEOSGeom_destroy(pos);
if ( 0 == contains )
{
/* Original geometry doesn't contain
* a point in this ring, must be an hole
*/
continue;
}
out->geoms[out->ngeoms++] = GEOS2LWGEOM(p, hasZ);
}
GEOSGeom_destroy(g1);
GEOSGeom_destroy(g2);
GEOSGeom_destroy(g1_bounds);
GEOSGeom_destroy((GEOSGeometry*)vgeoms[0]);
GEOSGeom_destroy(polygons);
return (LWGEOM*)out;
}
// Tiny triangle, see http://trac.osgeo.org/geos/ticket/559
template<>
template<>
void object::test<4>()
{
geom1_ = GEOSGeomFromWKT(
"POLYGON(( \
56.528666666700 25.2101666667, \
56.529000000000 25.2105000000, \
56.528833333300 25.2103333333, \
56.528666666700 25.2101666667))");
ensure( 0 != geom1_ );
geom2_ = GEOSPointOnSurface(geom1_);
ensure( 0 != geom2_ );
wkt_ = GEOSWKTWriter_write(wktw_, geom2_);
ensure_equals(std::string(wkt_), std::string( "POINT (56.528917 25.210417)" ) );
}
// Empty geometry -- see http://trac.osgeo.org/geos/ticket/560
template<>
template<>
void object::test<5>()
{
geom1_ = GEOSGeomFromWKT("LINESTRING EMPTY");
