Files
2026-05-31 10:17:09 +07:00

76 lines
3.1 KiB
Python

# IfcOpenShell - IFC toolkit and geometry engine
# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
#
# This file is part of IfcOpenShell.
#
# IfcOpenShell is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# IfcOpenShell is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with IfcOpenShell. If not, see <http://www.gnu.org/licenses/>.
import ifcopenshell
import ifcopenshell.api.owner
import ifcopenshell.util.element
def unassign_object(file: ifcopenshell.file, products: list[ifcopenshell.entity_instance]) -> None:
"""Unassigns products from their aggregate
A product (i.e. a smaller part of a whole) may be aggregated into zero
or one larger space or element. This function will remove that
aggregation relationship.
As all physical IFC model elements must be part of a hierarchical tree
called the "spatial decomposition", using this function will remove the
product from that tree. This is a dangerous operation and may result in
the product no longer being visible in IFC applications.
If the product is not part of an aggregation relationship, nothing will
happen.
:param products: The list of parts of the aggregate, typically of IfcElements or
IfcSpatialStructureElement subclass
:return: None
Example:
.. code:: python
element = ifcopenshell.api.root.create_entity(model, ifc_class="IfcSite")
subelement1 = ifcopenshell.api.root.create_entity(model, ifc_class="IfcBuilding")
subelement2 = ifcopenshell.api.root.create_entity(model, ifc_class="IfcBuilding")
ifcopenshell.api.aggregate.assign_object(model, products=[subelement1], relating_object=element)
ifcopenshell.api.aggregate.assign_object(model, products=[subelement2], relating_object=element)
# nothing is returned
ifcopenshell.api.aggregate.unassign_object(model, products=[subelement1])
# nothing is returned, relationship is removed
ifcopenshell.api.aggregate.unassign_object(model, products=[subelement2])
"""
settings = {"products": products}
products = set(settings["products"])
rels = set(
rel
for product in products
if (rel := next((rel for rel in product.Decomposes if rel.is_a("IfcRelAggregates")), None))
)
for rel in rels:
related_objects = set(rel.RelatedObjects) - products
if related_objects:
rel.RelatedObjects = list(related_objects)
ifcopenshell.api.owner.update_owner_history(file, element=rel)
else:
history = rel.OwnerHistory
file.remove(rel)
if history:
ifcopenshell.util.element.remove_deep2(file, history)