def getRings(self, geometry):
rings = []
# TODO: remove when the error is resolved
# Error: The expected object type is a QgsCurvePolygon but it receives a QgsPoint, however the WKT of the
# QgsPoint corresponds to either a QgsPolygon or QgsMultiPolygon (yeap, it must be a bug in QGIS)
if type(geometry) == QgsPoint or type(geometry) == QgsLineString:
geom = QgsGeometry().fromWkt(geometry.asWkt())
curve = None
if geom.isMultipart():
curve = QgsMultiPolygon()
curve.fromWkt(geom.asWkt())
else:
curve = QgsPolygon()
curve.fromWkt(geom.asWkt())
geometry = curve.toCurveType()
if isinstance(geometry, QgsGeometryCollection):
# collection
for i in range(geometry.numGeometries()):
if QgsWkbTypes.geometryType(geometry.geometryN(
i).wkbType()) == QgsWkbTypes.PolygonGeometry:
rings.extend(self.getRings(geometry.geometryN(i)))
else:
# Converts geometry to curve, because exteriorRing is a method from curve polygons
if isinstance(geometry, QgsPolygon):
geom = geometry.toCurveType()
geometry = geom
# not collection
rings.append(geometry.exteriorRing().clone())
for i in range(geometry.numInteriorRings()):
rings.append(geometry.interiorRing(i).clone())
return rings
def get_inner_rings_layer(self,
plot_layer,
id_field=ID_FIELD,
use_selection=False):
id_field_idx = plot_layer.fields().indexFromName(id_field)
request = QgsFeatureRequest().setSubsetOfAttributes([id_field_idx])
polygons = plot_layer.getSelectedFeatures(
request) if use_selection else plot_layer.getFeatures(request)
layer = QgsVectorLayer("LineString?crs=EPSG:{}".format(DEFAULT_EPSG),
"rings", "memory")
data_provider = layer.dataProvider()
data_provider.addAttributes([QgsField(ID_FIELD, QVariant.Int)])
layer.updateFields()
features = []
for polygon in polygons:
polygon_geom = polygon.geometry()
is_multipart = polygon_geom.isMultipart()
# Does the current multipolygon have inner rings?
has_inner_rings = False
multi_polygon = None
single_polygon = None
if is_multipart:
multi_polygon = polygon_geom.constGet()
# TODO: remove when the error is resolved
if type(multi_polygon) != QgsMultiPolygon:
geom = QgsMultiPolygon()
geom.fromWkt(polygon_geom.asWkt())
multi_polygon = geom
for part in range(multi_polygon.numGeometries()):
if multi_polygon.ringCount(part) > 1:
has_inner_rings = True
break
else:
single_polygon = polygon_geom.constGet()
# TODO: remove when the error is resolved
if type(single_polygon) != QgsPolygon:
geom = QgsPolygon()
geom.fromWkt(polygon_geom.asWkt())
single_polygon = geom
if single_polygon.numInteriorRings() > 0:
has_inner_rings = True
if has_inner_rings:
if is_multipart and multi_polygon:
for i in range(multi_polygon.numGeometries()):
temp_polygon = multi_polygon.geometryN(i)
# TODO: remove when the error is resolved
if type(temp_polygon) != QgsPolygon:
geom = QgsPolygon()
geom.fromWkt(temp_polygon.asWkt())
temp_polygon = geom
for j in range(temp_polygon.numInteriorRings()):
new_feature = QgsVectorLayerUtils().createFeature(
layer,
QgsGeometry(
temp_polygon.interiorRing(j).clone()),
{0: polygon[id_field]})
features.append(new_feature)
elif not is_multipart and single_polygon:
for j in range(single_polygon.numInteriorRings()):
new_feature = QgsVectorLayerUtils().createFeature(
layer,
QgsGeometry(
single_polygon.interiorRing(j).clone()),
{0: polygon[id_field]})
features.append(new_feature)
layer.dataProvider().addFeatures(features)
layer.updateExtents()
layer.reload()
return layer
