Own iterator geometry results

Return independent geometry copies with unique ownership, preserve parent lifetimes, and teach the Python wrapper to own derived results. Keep serializer inputs non-owning and replace Collada's deferred object with copied triangulation elements.\n\nGenerated with the assistance of an AI coding tool.

src/ifcconvert/IfcConvert.cpp

@@ -933,15 +933,15 @@ int main(int argc, char** argv) {
 
 	while (true) {
 		
-		ifcopenshell::geom::element* geom_object = context_iterator->get();
+		auto geom_object = context_iterator->get();
 
 		if (is_tesselated)
 		{
-			serializer->write(static_cast<const ifcopenshell::geom::triangulation_element*>(geom_object));
+			serializer->write(static_cast<const ifcopenshell::geom::triangulation_element*>(geom_object.get()));
 		}
 		else
 		{
-			serializer->write(static_cast<const ifcopenshell::geom::brep_element*>(geom_object));
+			serializer->write(static_cast<const ifcopenshell::geom::brep_element*>(geom_object.get()));
 		}
 
         if (!no_progress) {
@@ -1412,7 +1412,7 @@ void fix_quantities(ifcopenshell::file& f, bool no_progress, bool quiet, bool st
 		if (num_created) {
 			has_more = context_iterator.next();
 		}
-		ifcopenshell::geom::brep_element* geom_object = nullptr;
+		std::unique_ptr<ifcopenshell::geom::brep_element> geom_object;
 		if (has_more) {
 			geom_object = context_iterator.get_native();
 		}

src/ifcconvert/validate_storey_containment.cpp

@@ -111,7 +111,7 @@ void fix_storeycontainment(ifcopenshell::file& f, bool no_progress, bool quiet,
 		if (num_created) {
 			has_more = context_iterator.next();
 		}
-		ifcopenshell::geom::brep_element* geom_object = nullptr;
+		std::unique_ptr<ifcopenshell::geom::brep_element> geom_object;
 		if (has_more) {
 			geom_object = context_iterator.get_native();
 		}

src/ifcconvert/validation_utils.h

@@ -477,7 +477,7 @@ struct intersection_validator {
 			if (num_created) {
 				has_more = context_iterator.next();
 			}
-			ifcopenshell::geom::brep_element* geom_object = nullptr;
+			std::unique_ptr<ifcopenshell::geom::brep_element> geom_object;
 			if (has_more) {
 				geom_object = context_iterator.get_native();
 			}

src/ifcgeom/element.h

@@ -22,6 +22,7 @@
 
 #include <string>
 #include <algorithm>
+#include <memory>
 
 #include "../ifcparse/argument.h"
 #include "../ifcparse/global_id.h"
@@ -73,8 +74,20 @@ namespace ifcopenshell::geom {
 		std::string _context;
 		std::string _unique_id;
 		ifcopenshell::geom::transformation _transformation;
-        const express::entity product_;
+		const express::entity product_;
 		std::vector<const ifcopenshell::geom::element*> _parents;
+		std::vector<std::shared_ptr<const ifcopenshell::geom::element>> _parent_storage;
+
+		friend class iterator;
+		virtual std::unique_ptr<element> clone() const { return std::make_unique<element>(*this); }
+		void set_parents(std::vector<std::unique_ptr<ifcopenshell::geom::element>>&& newparents) {
+			_parents.clear();
+			_parent_storage.clear();
+			for (auto& parent : newparents) {
+				_parents.push_back(parent.get());
+				_parent_storage.emplace_back(std::move(parent));
+			}
+		}
 	public:
 
 		friend bool operator == (const element& element1, const element& element2) {
@@ -108,9 +121,12 @@ namespace ifcopenshell::geom {
 		const std::string& context() const { return _context; }
 		const std::string& unique_id() const { return _unique_id; }
 		const ifcopenshell::geom::transformation& transformation() const { return _transformation; }
-        const express::entity& product() const { return product_; }
+		const express::entity& product() const { return product_; }
 		const std::vector<const ifcopenshell::geom::element*>& parents() const { return _parents; }
-		void SetParents(std::vector<const ifcopenshell::geom::element*>& newparents) { _parents = newparents; }
+		void SetParents(std::vector<const ifcopenshell::geom::element*>& newparents) {
+			_parent_storage.clear();
+			_parents = newparents;
+		}
 
 		element(const ifcopenshell::geom::settings& settings, int id, int parent_id, const std::string& name, const std::string& type,
             const std::string& guid, const std::string& context, const ifcopenshell::geom::taxonomy::matrix4::ptr& trsf, const express::entity& product)
@@ -158,9 +174,10 @@ namespace ifcopenshell::geom {
 		bool calculate_projected_surface_area(double& along_x, double& along_y, double& along_z) const {
 			return geometry().calculate_projected_surface_area(this->transformation().data(), along_x, along_y, along_z);
 		}
+		brep_element(const brep_element& other) = default;
 	private:
-		brep_element(const brep_element& other);
 		brep_element& operator=(const brep_element& other);
+		std::unique_ptr<element> clone() const override { return std::make_unique<brep_element>(*this); }
 	};
 
 	class triangulation_element : public element {
@@ -177,26 +194,25 @@ namespace ifcopenshell::geom {
 			: element(source)
 			, _geometry(geometry)
 		{}
+		triangulation_element(const triangulation_element& other) = default;
 	private:
-		triangulation_element(const triangulation_element& other);
 		triangulation_element& operator=(const triangulation_element& other);
+		std::unique_ptr<element> clone() const override { return std::make_unique<triangulation_element>(*this); }
 	};
 
 	class serialized_element : public element {
 	private:
-		ifcopenshell::geom::Representation::serialization* _geometry;
+		boost::shared_ptr<ifcopenshell::geom::Representation::serialization> _geometry;
 	public:
 		const ifcopenshell::geom::Representation::serialization& geometry() const { return *_geometry; }
 		serialized_element(const brep_element& shape_model)
 			: element(shape_model)
-			, _geometry(new ifcopenshell::geom::Representation::serialization(shape_model.geometry()))
+			, _geometry(boost::shared_ptr<ifcopenshell::geom::Representation::serialization>(new ifcopenshell::geom::Representation::serialization(shape_model.geometry())))
 		{}
-		virtual ~serialized_element() {
-			delete _geometry;
-		}
+		serialized_element(const serialized_element& other) = default;
 	private:
-		serialized_element(const serialized_element& other);
 		serialized_element& operator=(const serialized_element& other);
+		std::unique_ptr<element> clone() const override { return std::make_unique<serialized_element>(*this); }
 	};
 }
 

src/ifcgeom/iterator.cpp

@@ -301,8 +301,8 @@ void ifcopenshell::geom::iterator::compute_bounds(bool with_geometry)
 	if (with_geometry) {
 		size_t num_created = 0;
 		do {
-			ifcopenshell::geom::element* geom_object = get();
-			const ifcopenshell::geom::triangulation_element* o = static_cast<const ifcopenshell::geom::triangulation_element*>(geom_object);
+			auto geom_object = get();
+			const ifcopenshell::geom::triangulation_element* o = static_cast<const ifcopenshell::geom::triangulation_element*>(geom_object.get());
 			const ifcopenshell::geom::Representation::triangulation& mesh = o->geometry();
 			auto mat = o->transformation().data()->ccomponents();
 			Eigen::Vector4d vec, transformed;
@@ -548,7 +548,7 @@ express::base ifcopenshell::geom::iterator::next() {
 }
 
 /// Gets the representation of the current geometrical entity.
-ifcopenshell::geom::element* ifcopenshell::geom::iterator::get()
+std::unique_ptr<ifcopenshell::geom::element> ifcopenshell::geom::iterator::get()
 {
 	validate_iterator_state();
 
@@ -558,24 +558,24 @@ ifcopenshell::geom::element* ifcopenshell::geom::iterator::get()
 	if (settings_.get<ifcopenshell::geom::settings::UseElementHierarchy>().get()) {
 		// We are going to build a vector with the element parents.
 		// First, create the parent vector
-		std::vector<const ifcopenshell::geom::element*> parents;
+		std::vector<std::unique_ptr<ifcopenshell::geom::element>> parents;
 
 		// if the element has a parent
 		if (ret->parent_id() != -1) {
-			const ifcopenshell::geom::element* parent_object = NULL;
+			ifcopenshell::geom::element* parent_object = NULL;
 			bool hasParent = true;
 
 			// get the parent
 			try {
-				parent_object = get_object(ret->parent_id());
+				auto parent = get_object(ret->parent_id());
+				parent_object = parent.get();
+				parents.insert(parents.begin(), std::move(parent));
 			} catch (const std::exception& e) {
 				logger_.error("GEO", 56, e);
 				hasParent = false;
 			}
 
 			// Add the previously found parent to the vector
-			if (hasParent) parents.insert(parents.begin(), parent_object);
-
 			// We need to find all the parents
 			while (parent_object != NULL && hasParent && parent_object->parent_id() != -1) {
 				// Find the next parent
@@ -585,7 +585,9 @@ ifcopenshell::geom::element* ifcopenshell::geom::iterator::get()
                     hasParent = false;
                 } else {
 					try {
-						parent_object = get_object(pid);
+						auto parent = get_object(pid);
+						parent_object = parent.get();
+						parents.insert(parents.begin(), std::move(parent));
 					} catch (const std::exception& e) {
 						logger_.error("GEO", 57, e);
 						hasParent = false;
@@ -593,20 +595,18 @@ ifcopenshell::geom::element* ifcopenshell::geom::iterator::get()
                 }
 				
 				// Add the previously found parent to the vector
-				if (hasParent) parents.insert(parents.begin(), parent_object);
-
 				hasParent = hasParent && parent_object->parent_id() != -1;
 			}
 
 			// when done push the parent list in the element object
-			ret->SetParents(parents);
+			ret->set_parents(std::move(parents));
 		}
 	}
 
-	return ret;
+	return ret->clone();
 }
 
-const ifcopenshell::geom::element* ifcopenshell::geom::iterator::get_object(int id) {
+std::unique_ptr<ifcopenshell::geom::element> ifcopenshell::geom::iterator::get_object(int id) {
 	ifcopenshell::geom::taxonomy::matrix4::ptr m4;
 	int parent_id = -1;
 	std::string instance_type, product_name, product_guid;
@@ -639,8 +639,7 @@ const ifcopenshell::geom::element* ifcopenshell::geom::iterator::get_object(int
 		logger_.error("GEO", 59, "Unknown error returning product");
 	}
 
-	element* ifc_object = new element(settings_, id, parent_id, product_name, instance_type, product_guid, "", m4, ifc_product.as<express::entity>());
-	return ifc_object;
+	return std::make_unique<element>(settings_, id, parent_id, product_name, instance_type, product_guid, "", m4, ifc_product.as<express::entity>());
 }
 
 express::base ifcopenshell::geom::iterator::create() {

src/ifcgeom/iterator.h

@@ -44,7 +44,7 @@
  *   at least a single representation will process successfully				 *
  *																			  *
  * ifcopenshell::geom::iterator::get()													 *
- *   returns a pointer to the current ifcopenshell::geom::element						  *
+ *   returns an owned copy of the current ifcopenshell::geom::element				  *
  *																			  *
  * ifcopenshell::geom::iterator::next()													*
  *   returns true iff a following entity is available for a successive call to  *
@@ -291,15 +291,16 @@ namespace ifcopenshell::geom {
 		express::base next();
 
 		/// Gets the representation of the current geometrical entity.
-		element* get();
+		std::unique_ptr<element> get();
 
 		/// Gets the native (Open Cascade or CGAL) representation of the current geometrical entity.
-		brep_element* get_native()
+		std::unique_ptr<brep_element> get_native()
 		{
-			return *native_task_result_iterator_;
+			validate_iterator_state();
+			return std::make_unique<brep_element>(**native_task_result_iterator_);
 		}
 
-		const element* get_object(int id);
+		std::unique_ptr<element> get_object(int id);
 
 		express::base create();
 	};

src/ifcgeom/kernels/opencascade/tree.h

@@ -1496,7 +1496,8 @@ namespace ifcopenshell::geom {
 		void add_file(ifcopenshell::geom::iterator& it) {
 			if (it.initialize()) {
 				do {
-					add_element(dynamic_cast<ifcopenshell::geom::brep_element*>(it.get()));
+					auto element = it.get();
+					add_element(dynamic_cast<ifcopenshell::geom::brep_element*>(element.get()));
 				} while (it.next());
 			}
 		}

src/ifcgeom/kernels/opencascade/tree_backends.h

@@ -56,7 +56,8 @@ namespace ifcopenshell {
 						ifcopenshell::geom::iterator iterator(ifcopenshell::geom::kernels::construct(&file, "opencascade", settings_), settings_, &file, {}, 1);
 						if (iterator.initialize()) {
 							do {
-								add_element(iterator.get());
+								auto element = iterator.get();
+								add_element(element.get());
 							} while (iterator.next());
 						}
 					}
@@ -139,7 +140,8 @@ namespace ifcopenshell {
 						ifcopenshell::geom::iterator iterator(ifcopenshell::geom::kernels::construct(&file, "opencascade", settings_), settings_, &file, {}, 1);
 						if (iterator.initialize()) {
 							do {
-								add_element(iterator.get());
+								auto element = iterator.get();
+								add_element(element.get());
 							} while (iterator.next());
 						}
 					}

src/ifcgeom/tree.cpp

@@ -151,7 +151,8 @@ void ifcopenshell::geom::tree::add_file(ifcopenshell::geom::iterator& iterator)
 	}
 
 	do {
-		add_element(iterator.get());
+		auto element = iterator.get();
+		add_element(element.get());
 	} while (iterator.next());
 }
 

src/ifcgeomserver/IfcGeomServer.cpp

@@ -617,12 +617,14 @@ int main () {
 				exit_code = 1;
 				break;
 			}
-			const ifcopenshell::geom::triangulation_element* geom = static_cast<const ifcopenshell::geom::triangulation_element*>(iterator->get());
+			auto element = iterator->get();
+			const ifcopenshell::geom::triangulation_element* geom = static_cast<const ifcopenshell::geom::triangulation_element*>(element.get());
+			auto native_element = iterator->get_native();
 			std::unique_ptr<EntityExtension> eext;
 			if (emit_quantities) {
-				eext.reset(new QuantityWriter_v1(iterator->get_native()));
+				eext.reset(new QuantityWriter_v1(native_element.get()));
 			} else {
-				eext.reset(new QuantityWriter_v0(iterator->get_native()));
+				eext.reset(new QuantityWriter_v0(native_element.get()));
 			}
 			Entity(geom, eext.get()).write(std::cout);
 			continue;

src/ifcviewer/GeometryStreamer.cpp

@@ -539,7 +539,8 @@ void GeometryStreamer::run(const std::string& path, int num_threads) {
             do {
                 if (cancel_requested_.load()) break;
 
-                const ifcopenshell::geom::element* elem = iterator->get();
+				auto element = iterator->get();
+				const ifcopenshell::geom::element* elem = element.get();
                 if (!elem) continue;
 
                 const auto* tri_elem = dynamic_cast<const ifcopenshell::geom::triangulation_element*>(elem);

src/ifcwrap/IfcGeomWrapper.i

@@ -103,6 +103,28 @@
 	}
 }
 
+// Iterator results are copies owned by the caller. Release the unique pointer
+// into the most specific Python proxy and transfer deletion to Python.
+%typemap(out) std::unique_ptr<ifcopenshell::geom::element> {
+	ifcopenshell::geom::element* elem = $1.release();
+	ifcopenshell::geom::serialized_element* serialized_elem = dynamic_cast<ifcopenshell::geom::serialized_element*>(elem);
+	ifcopenshell::geom::triangulation_element* triangulation_elem = dynamic_cast<ifcopenshell::geom::triangulation_element*>(elem);
+	ifcopenshell::geom::brep_element* brep_elem = dynamic_cast<ifcopenshell::geom::brep_element*>(elem);
+	if (triangulation_elem) {
+		$result = SWIG_NewPointerObj(SWIG_as_voidptr(triangulation_elem), SWIGTYPE_p_ifcopenshell__geom__triangulation_element, SWIG_POINTER_OWN);
+	} else if (serialized_elem) {
+		$result = SWIG_NewPointerObj(SWIG_as_voidptr(serialized_elem), SWIGTYPE_p_ifcopenshell__geom__serialized_element, SWIG_POINTER_OWN);
+	} else if (brep_elem) {
+		$result = SWIG_NewPointerObj(SWIG_as_voidptr(brep_elem), SWIGTYPE_p_ifcopenshell__geom__brep_element, SWIG_POINTER_OWN);
+	} else {
+		$result = SWIG_NewPointerObj(SWIG_as_voidptr(elem), SWIGTYPE_p_ifcopenshell__geom__element, SWIG_POINTER_OWN);
+	}
+}
+
+%typemap(out) std::unique_ptr<ifcopenshell::geom::brep_element> {
+	$result = SWIG_NewPointerObj(SWIG_as_voidptr($1.release()), SWIGTYPE_p_ifcopenshell__geom__brep_element, SWIG_POINTER_OWN);
+}
+
 %newobject ifcopenshell::geom::Representation::brep::item;
 %newobject ifcopenshell::geom::Representation::brep::as_compound;
 

src/serializers/collada_serializer.cpp

@@ -387,29 +387,10 @@ void collada_serializer::collada_exporter::startDocument(const std::string& unit
 void collada_serializer::collada_exporter::write(const ifcopenshell::geom::triangulation_element* o)
 {
 	const ifcopenshell::geom::Representation::triangulation& mesh = o->geometry();
-	
-    std::string name = serializer->object_id(o);
-	collada_id(name);
-	
-	std::string representation_id = "representation-" + o->geometry().id();
-	collada_id(representation_id);
-
-	std::vector<std::string> material_references;
 	BOOST_FOREACH(const ifcopenshell::geom::taxonomy::style::ptr& material, mesh.materials()) {
 		materials.add(material);
-
-		std::string material_name = materials.getMaterialUri(material);
-		material_references.push_back(material_name);
 	}
-
-	deferred_object deferred(name, representation_id, o->type(), o->transformation(), mesh.verts(), mesh.normals(),
-		mesh.faces(), mesh.edges(), mesh.material_ids(), mesh.materials(), material_references, mesh.uvs());
-
-	if (serializer->settings().get<ifcopenshell::geom::settings::UseElementHierarchy>().get()) {
-		deferred.parents() = o->parents();
-	}
-
-	deferreds.push_back(deferred);
+	deferreds.push_back(std::make_unique<ifcopenshell::geom::triangulation_element>(*o));
 }
 
 std::string collada_serializer::differentiateSlabTypes(const express::entity& slab)
@@ -467,25 +448,53 @@ void collada_serializer::collada_exporter::endDocument() {
 	//if the setting USE_ELEMENT_HIERARCHY is in use, we sort the deferreds objects by their parents.
 	
 	if (use_hierarchy) {
-		std::sort(deferreds.begin(), deferreds.end());
+		std::sort(deferreds.begin(), deferreds.end(), [](const auto& first, const auto& second) {
+			const auto& first_parents = first->parents();
+			const auto& second_parents = second->parents();
+			const size_t size = (std::min)(first_parents.size(), second_parents.size());
+			size_t index = 0;
+			while (index < size && *first_parents[index] == *second_parents[index]) {
+				++index;
+			}
+			return index >= size
+				? first_parents.size() < second_parents.size()
+				: *first_parents[index] < *second_parents[index];
+		});
 	}
 	
-	for (std::vector<deferred_object>::const_iterator it = deferreds.begin(); it != deferreds.end(); ++it) {
-		if (geometries_written.find(it->representation_id) != geometries_written.end()) {
+	for (const auto& object_pointer : deferreds) {
+		const auto& object = *object_pointer;
+		std::string representation_id = "representation-" + object.geometry().id();
+		collada_id(representation_id);
+		if (geometries_written.find(representation_id) != geometries_written.end()) {
 			continue;
 		}
-		geometries_written.insert(it->representation_id);
-		geometries.write(it->representation_id, it->type, it->vertices, it->normals, it->faces, it->edges,
-            it->material_ids, it->materials, it->uvs, it->material_references);
+		geometries_written.insert(representation_id);
+		const auto& mesh = object.geometry();
+		std::vector<std::string> material_references;
+		for (const auto& material : mesh.materials()) {
+			material_references.push_back(materials.getMaterialUri(material));
+		}
+		geometries.write(representation_id, object.type(), mesh.verts(), mesh.normals(), mesh.faces(), mesh.edges(),
+            mesh.material_ids(), mesh.materials(), mesh.uvs(), material_references);
 	}
 	geometries.close();
 
-	for (std::vector<deferred_object>::const_iterator it = deferreds.begin(); it != deferreds.end(); ++it){
-		const std::string object_name = it->unique_id;
+	for (const auto& object_pointer : deferreds) {
+		const auto& object = *object_pointer;
+		std::string object_name = serializer->object_id(&object);
+		collada_id(object_name);
+		std::string representation_id = "representation-" + object.geometry().id();
+		collada_id(representation_id);
+		std::vector<std::string> material_references;
+		for (const auto& material : object.geometry().materials()) {
+			material_references.push_back(materials.getMaterialUri(material));
+		}
 
 		if (use_hierarchy)
 		{
-			size_t parentsNumber = it->parents_.size();
+			const auto& parents = object.parents();
+			size_t parentsNumber = parents.size();
 			bool finished = false;
 
 			// If we have no parent in the stack and the object has no parent, nothing to do : skip the loop
@@ -496,17 +505,17 @@ void collada_serializer::collada_exporter::endDocument() {
 				// If we need to add a parent
 				if (serializer->parentStackId.size() <= parentsNumber)
 				{
-					if (serializer->parentStackId.empty()) { scene.addParent(*(it->parents_.at(0))); }
+					if (serializer->parentStackId.empty()) { scene.addParent(*parents.at(0)); }
 					else
 					{
 						size_t diff = parentsNumber - serializer->parentStackId.size();
 
 						// If we have the wrong parent in the list
-						if (serializer->parentStackId.top() != it->parents_.at(parentsNumber - diff - 1)->id()) {
+						if (serializer->parentStackId.top() != parents.at(parentsNumber - diff - 1)->id()) {
 							scene.closeParent();
 						} else {
 							// So far we have the right parents, we just need to add the missing ones
-							for (size_t i = parentsNumber - diff; i < parentsNumber; i++) { scene.addParent(*(it->parents_.at(i))); }
+							for (size_t i = parentsNumber - diff; i < parentsNumber; i++) { scene.addParent(*parents.at(i)); }
 
 							// if diff == 0, we can leave the loop. In fact we have the right number of parents, and the last one is ok
 							if (diff == 0) { finished = true; }
@@ -520,7 +529,7 @@ void collada_serializer::collada_exporter::endDocument() {
 		}
 		
         /// @todo redundant information using ID as both ID and Name, maybe omit Name or allow specifying what would be used as the name
-		scene.add(object_name, object_name, it->representation_id, it->material_references, it->transformation);
+		scene.add(object_name, object_name, representation_id, material_references, object.transformation());
 	}
 
 	//close the remaining parent tags.

src/serializers/collada_serializer.h

@@ -70,7 +70,6 @@ private:
 			{}
             void addFloatSource(const std::string& mesh_id, const std::string& suffix,
                 const std::vector<double>& floats, const char* coords = "XYZ");
-            /// @todo pass simply deferred_object?
             void write(
                 const std::string &mesh_id, const std::string &default_material_name,
                 const std::vector<double>& positions, const std::vector<double>& normals,
@@ -138,59 +137,6 @@ private:
             collada_effects effects;
 		};
 
-		class deferred_object {
-		
-			friend bool operator < (const deferred_object& def_obj1, const deferred_object& def_obj2) {
-				size_t size = (def_obj1.parents_.size() < def_obj2.parents_.size() ? def_obj1.parents_.size() : def_obj2.parents_.size());
-				size_t cpt = 0;
-
-				// Skip the shared parents
-				while (cpt < size && *(def_obj1.parents_.at(cpt)) == *(def_obj2.parents_.at(cpt))) {
-					cpt++;
-				}
-
-				// If a parent list container the other one
-				if (cpt >= size) {
-					return def_obj1.parents_.size() < def_obj2.parents_.size();
-				} else {
-					return *(def_obj1.parents_.at(cpt)) < *(def_obj2.parents_.at(cpt));
-				}
-			}
-
-		public:
-			std::string unique_id, representation_id, type;
-			ifcopenshell::geom::transformation transformation;
-			std::vector<double> vertices;
-			std::vector<double> normals;
-			std::vector<int> faces;
-			std::vector<int> edges;
-			std::vector<int> material_ids;
-			std::vector<ifcopenshell::geom::taxonomy::style::ptr> materials;
-			std::vector<std::string> material_references;
-            std::vector<double> uvs;
-			std::vector<const ifcopenshell::geom::element*> parents_;
-
-			deferred_object(const std::string& unique_id, const std::string& representation_id, const std::string& type, const ifcopenshell::geom::transformation& transformation,
-				const std::vector<double>& vertices, const std::vector<double>& normals, const std::vector<int>& faces,
-				const std::vector<int>& edges, const std::vector<int>& material_ids, const std::vector<ifcopenshell::geom::taxonomy::style::ptr>& materials,
-				const std::vector<std::string>& material_references, const std::vector<double>& uvs)
-				: unique_id(unique_id)
-				, representation_id(representation_id)
-				, type(type)
-				, transformation(transformation)
-				, vertices(vertices)
-				, normals(normals)
-				, faces(faces)
-				, edges(edges)
-				, material_ids(material_ids)
-				, materials(materials)
-				, material_references(material_references)
-				, uvs(uvs)
-			{}
-
-			std::vector<const ifcopenshell::geom::element*>& parents() { return parents_; }
-			const std::vector<const ifcopenshell::geom::element*>& parents() const { return parents_; }
-		};
 		COLLADABU::NativeString filename;
 		COLLADASW::StreamWriter stream;
 		collada_scene scene;
@@ -209,7 +155,7 @@ private:
         collada_materials materials;
         collada_geometries geometries;
         collada_serializer *serializer;
-		std::vector<deferred_object> deferreds;
+		std::vector<std::unique_ptr<ifcopenshell::geom::triangulation_element>> deferreds;
 		virtual ~collada_exporter() {}
 		void startDocument(const std::string& unit_name, float unit_magnitude);
 		void write(const ifcopenshell::geom::triangulation_element* o);