OGRMultiPolygon* OGRILI1Layer::Polygonize( OGRGeometryCollection* poLines, bool fix_crossing_lines )
{
OGRMultiPolygon *poPolygon = new OGRMultiPolygon();
if (poLines->getNumGeometries() == 0) return poPolygon;
#if defined(HAVE_GEOS)
GEOSGeom *ahInGeoms = NULL;
int i = 0;
OGRGeometryCollection *poNoncrossingLines = poLines;
GEOSGeom hResultGeom = NULL;
OGRGeometry *poMP = NULL;
if (fix_crossing_lines && poLines->getNumGeometries() > 0)
{
CPLDebug( "OGR_ILI", "Fixing crossing lines");
//A union of the geometry collection with one line fixes invalid geometries
poNoncrossingLines = (OGRGeometryCollection*)poLines->Union(poLines->getGeometryRef(0));
CPLDebug( "OGR_ILI", "Fixed lines: %d", poNoncrossingLines->getNumGeometries()-poLines->getNumGeometries());
}
GEOSContextHandle_t hGEOSCtxt = OGRGeometry::createGEOSContext();
ahInGeoms = (GEOSGeom *) CPLCalloc(sizeof(void*),poNoncrossingLines->getNumGeometries());
for( i = 0; i < poNoncrossingLines->getNumGeometries(); i++ )
ahInGeoms[i] = poNoncrossingLines->getGeometryRef(i)->exportToGEOS(hGEOSCtxt);
hResultGeom = GEOSPolygonize_r( hGEOSCtxt,
ahInGeoms,
poNoncrossingLines->getNumGeometries() );
for( i = 0; i < poNoncrossingLines->getNumGeometries(); i++ )
GEOSGeom_destroy_r( hGEOSCtxt, ahInGeoms[i] );
CPLFree( ahInGeoms );
if (poNoncrossingLines != poLines) delete poNoncrossingLines;
if( hResultGeom == NULL )
{
OGRGeometry::freeGEOSContext( hGEOSCtxt );
return NULL;
}
poMP = OGRGeometryFactory::createFromGEOS( hGEOSCtxt, hResultGeom );
GEOSGeom_destroy_r( hGEOSCtxt, hResultGeom );
OGRGeometry::freeGEOSContext( hGEOSCtxt );
return (OGRMultiPolygon *) poMP;
#endif
return poPolygon;
}
SEXP rgeos_polygonize(SEXP env, SEXP obj, SEXP id, SEXP p4s, SEXP cutEdges) {
GEOSContextHandle_t GEOShandle = getContextHandle(env);
int getCutEdges = LOGICAL_POINTER(cutEdges)[0];
int n = length(obj);
GEOSGeom *geoms = (GEOSGeom *) R_alloc((size_t) n, sizeof(GEOSGeom));
for(int i=0; i<n; i++) {
geoms[i] = rgeos_convert_R2geos(env, VECTOR_ELT(obj,i));
}
GEOSGeom res = (getCutEdges)
? GEOSPolygonizer_getCutEdges_r(GEOShandle, (const GEOSGeometry *const *) geoms, (unsigned int) n)
: GEOSPolygonize_r(GEOShandle, (const GEOSGeometry *const *) geoms, (unsigned int) n);
return( rgeos_convert_geos2R(env, res, p4s, id) );
}
Q_NOWARN_UNREACHABLE_PUSH
static GEOSGeometry *LWGEOM_GEOS_buildArea( const GEOSGeometry *geom_in, QString &errorMessage )
{
GEOSContextHandle_t handle = QgsGeos::getGEOSHandler();
GEOSGeometry *tmp = nullptr;
GEOSGeometry *shp = nullptr;
GEOSGeometry *geos_result = nullptr;
int srid = GEOSGetSRID_r( handle, geom_in );
GEOSGeometry const *vgeoms[1];
vgeoms[0] = geom_in;
try
{
geos_result = GEOSPolygonize_r( handle, vgeoms, 1 );
}
catch ( GEOSException &e )
{
errorMessage = QStringLiteral( "GEOSPolygonize(): %1" ).arg( e.what() );
return nullptr;
}
// We should now have a collection
#if PARANOIA_LEVEL > 0
if ( GEOSGeometryTypeId_r( handle, geos_result ) != COLLECTIONTYPE )
{
GEOSGeom_destroy_r( handle, geos_result );
errorMessage = "Unexpected return from GEOSpolygonize";
return nullptr;
}
#endif
int ngeoms = GEOSGetNumGeometries_r( handle, geos_result );
// No geometries in collection, early out
if ( ngeoms == 0 )
{
GEOSSetSRID_r( handle, geos_result, srid );
return geos_result;
}
// Return first geometry if we only have one in collection,
// to avoid the unnecessary Geometry clone below.
if ( ngeoms == 1 )
{
tmp = ( GEOSGeometry * )GEOSGetGeometryN_r( handle, geos_result, 0 );
if ( ! tmp )
{
GEOSGeom_destroy_r( handle, geos_result );
return nullptr;
}
shp = GEOSGeom_clone_r( handle, tmp );
GEOSGeom_destroy_r( handle, geos_result ); // only safe after the clone above
GEOSSetSRID_r( handle, shp, srid );
return shp;
}
/*
* Polygonizer returns a polygon for each face in the built topology.
*
* This means that for any face with holes we'll have other faces
* representing each hole. We can imagine a parent-child relationship
* between these faces.
*
* In order to maximize the number of visible rings in output we
* only use those faces which have an even number of parents.
*
* Example:
*
* +---------------+
* | L0 | L0 has no parents
* | +---------+ |
* | | L1 | | L1 is an hole of L0
* | | +---+ | |
* | | |L2 | | | L2 is an hole of L1 (which is an hole of L0)
* | | | | | |
* | | +---+ | |
* | +---------+ |
* | |
* +---------------+
*
* See http://trac.osgeo.org/postgis/ticket/1806
*
*/
// Prepare face structures for later analysis
Face **geoms = new Face*[ngeoms];
for ( int i = 0; i < ngeoms; ++i )
geoms[i] = newFace( GEOSGetGeometryN_r( handle, geos_result, i ) );
// Find faces representing other faces holes
findFaceHoles( geoms, ngeoms );
// Build a MultiPolygon composed only by faces with an
// even number of ancestors
tmp = collectFacesWithEvenAncestors( geoms, ngeoms );
// Cleanup face structures
for ( int i = 0; i < ngeoms; ++i )
delFace( geoms[i] );
delete [] geoms;
// Faces referenced memory owned by geos_result.
// It is safe to destroy geos_result after deleting them.
GEOSGeom_destroy_r( handle, geos_result );
// Run a single overlay operation to dissolve shared edges
shp = GEOSUnionCascaded_r( handle, tmp );
if ( !shp )
{
GEOSGeom_destroy_r( handle, tmp );
return nullptr;
}
GEOSGeom_destroy_r( handle, tmp );
GEOSSetSRID_r( handle, shp, srid );
return shp;
}
OGRMultiPolygon* OGRILI1Layer::Polygonize( OGRGeometryCollection* poLines, bool fix_crossing_lines )
{
if (poLines->getNumGeometries() == 0)
{
return new OGRMultiPolygon();
}
#if defined(HAVE_GEOS)
GEOSGeom *ahInGeoms = NULL;
OGRGeometryCollection *poNoncrossingLines = poLines;
GEOSGeom hResultGeom = NULL;
OGRGeometry *poMP = NULL;
if (fix_crossing_lines && poLines->getNumGeometries() > 0)
{
CPLDebug( "OGR_ILI", "Fixing crossing lines");
//A union of the geometry collection with one line fixes invalid geometries
OGRGeometry* poUnion = poLines->Union(poLines->getGeometryRef(0));
if( poUnion != NULL )
{
if( wkbFlatten(poUnion->getGeometryType()) == wkbGeometryCollection ||
wkbFlatten(poUnion->getGeometryType()) == wkbMultiLineString )
{
poNoncrossingLines = dynamic_cast<OGRGeometryCollection*>(poUnion);
CPLDebug( "OGR_ILI", "Fixed lines: %d", poNoncrossingLines->getNumGeometries()-poLines->getNumGeometries());
}
else
{
delete poUnion;
}
}
}
GEOSContextHandle_t hGEOSCtxt = OGRGeometry::createGEOSContext();
ahInGeoms = (GEOSGeom *) CPLCalloc(sizeof(void*),poNoncrossingLines->getNumGeometries());
for( int i = 0; i < poNoncrossingLines->getNumGeometries(); i++ )
ahInGeoms[i] = poNoncrossingLines->getGeometryRef(i)->exportToGEOS(hGEOSCtxt);
hResultGeom = GEOSPolygonize_r( hGEOSCtxt,
ahInGeoms,
poNoncrossingLines->getNumGeometries() );
for( int i = 0; i < poNoncrossingLines->getNumGeometries(); i++ )
GEOSGeom_destroy_r( hGEOSCtxt, ahInGeoms[i] );
CPLFree( ahInGeoms );
if (poNoncrossingLines != poLines) delete poNoncrossingLines;
if( hResultGeom == NULL )
{
OGRGeometry::freeGEOSContext( hGEOSCtxt );
return new OGRMultiPolygon();
}
poMP = OGRGeometryFactory::createFromGEOS( hGEOSCtxt, hResultGeom );
GEOSGeom_destroy_r( hGEOSCtxt, hResultGeom );
OGRGeometry::freeGEOSContext( hGEOSCtxt );
poMP = OGRGeometryFactory::forceToMultiPolygon( poMP );
if( poMP && wkbFlatten(poMP->getGeometryType()) == wkbMultiPolygon )
return dynamic_cast<OGRMultiPolygon *>(poMP);
else
{
delete poMP;
return new OGRMultiPolygon();
}
#else
return new OGRMultiPolygon();
#endif
}
