New recipe to extract out elements into its own IFC

src/ifcpatch/recipes/ExtractElements.py

@@ -0,0 +1,58 @@
+import ifcopenshell
+import ifcopenshell.util.selector
+
+
+class Patcher:
+    def __init__(self, src, file, logger, args=None):
+        self.src = src
+        self.file = file
+        self.logger = logger
+        self.args = args
+
+    def patch(self):
+        self.contained_ins = {}
+        self.aggregates = {}
+        self.new = ifcopenshell.file(schema=self.file.wrapped_data.schema)
+        self.owner_history = None
+        for owner_history in self.file.by_type("IfcOwnerHistory"):
+            self.owner_history = self.new.add(owner_history)
+            break
+        selector = ifcopenshell.util.selector.Selector()
+        for element in selector.parse(self.file, self.args[0]):
+            self.add_element(element)
+        self.create_spatial_tree()
+        self.file = self.new
+
+    def add_element(self, element):
+        new_element = self.new.add(element)
+        for rel in element.ContainedInStructure:
+            spatial_element = rel.RelatingStructure
+            new_spatial_element = self.new.add(spatial_element)
+            self.contained_ins.setdefault(spatial_element.GlobalId, set()).add(new_element)
+            self.add_spatial_tree(spatial_element, new_spatial_element)
+
+    def add_spatial_tree(self, spatial_element, new_spatial_element):
+        for rel in spatial_element.Decomposes:
+            new = self.new.add(rel.RelatingObject)
+            self.aggregates.setdefault(rel.RelatingObject.GlobalId, set()).add(new_spatial_element)
+            self.add_spatial_tree(rel.RelatingObject, new)
+
+    def create_spatial_tree(self):
+        for relating_structure, related_elements in self.contained_ins.items():
+            self.new.createIfcRelContainedInSpatialStructure(
+                ifcopenshell.guid.new(),
+                self.owner_history,
+                None,
+                None,
+                list(related_elements),
+                self.new.by_guid(relating_structure),
+            )
+        for relating_object, related_objects in self.aggregates.items():
+            self.new.createIfcRelAggregates(
+                ifcopenshell.guid.new(),
+                self.owner_history,
+                None,
+                None,
+                self.new.by_guid(relating_object),
+                list(related_objects),
+            )