Merge pull request #14 from aothms/master

Various fixes

src/examples/IfcOpenHouse.cpp

@@ -195,43 +195,46 @@ int main() {
 	file.addBuildingProduct(north_wall);
 	file.setSurfaceColour(north_wall->Representation(), wall_colour);
 
-	IfcSchema::IfcShapeRepresentation* clipped_wall_body_rep = file.addEmptyRepresentation();
-	file.addBox(clipped_wall_body_rep, 5000, 360, 6000);
-	// The east wall geometry is clipped using two IfcHalfSpaceSolids, created from an 
-	// 'axis 3d placement' that specifies the plane against which the geometry is clipped.
-	file.clipRepresentation(clipped_wall_body_rep, file.addPlacement3d(-2500, 0, 3000, -1, 0, 1), false);
-	file.clipRepresentation(clipped_wall_body_rep, file.addPlacement3d(2500, 0, 3000, 1, 0, 1), false);
+	// Two identical representations are created for the two remaining walls. Mapped items
+	// are not used, because it is not allowed by the standard for wall body representations.
+	// MappedItems are not allowed for Axis representations as per CV-2x3-161
+	IfcSchema::IfcProductDefinitionShape* clipped_wall_body_reps[2];
+	for (int i = 0; i < 2; ++i) {
+		IfcSchema::IfcShapeRepresentation* body = file.addEmptyRepresentation();
+		file.addBox(body, 5000, 360, 6000);
+		// The wall geometry is clipped using two IfcHalfSpaceSolids, created from an 
+		// 'axis 3d placement' that specifies the plane against which the geometry is clipped.
+		file.clipRepresentation(body, file.addPlacement3d(-2500, 0, 3000, -1, 0, 1), false);
+		file.clipRepresentation(body, file.addPlacement3d(2500, 0, 3000, 1, 0, 1), false);
+		file.setSurfaceColour(body, wall_colour);
+
+		IfcSchema::IfcShapeRepresentation* axis = file.addEmptyRepresentation("Axis", "Curve2D");
+		file.addAxis(axis, 5000);
+
+		IfcSchema::IfcRepresentation::list::ptr reps(new IfcSchema::IfcRepresentation::list);
+		reps->push(body);
+		reps->push(axis);
+		clipped_wall_body_reps[i] = new IfcSchema::IfcProductDefinitionShape(null, null, reps);
+	}
 
 	// Now create a wall on the east of the building, again starting with just a box shape
 	IfcSchema::IfcWallStandardCase* east_wall = new IfcSchema::IfcWallStandardCase(guid(), file.getSingle<IfcSchema::IfcOwnerHistory>(),
-		S("East wall"), null, null, file.addLocalPlacement(storey_placement, 4820, 2500, 0, 0, 0, 1, 0, 1, 0), file.addMappedItem(clipped_wall_body_rep), null
+		S("East wall"), null, null, file.addLocalPlacement(storey_placement, 4820, 2500, 0, 0, 0, 1, 0, 1, 0), clipped_wall_body_reps[0], null
 #ifdef USE_IFC4
 		, IfcSchema::IfcWallTypeEnum::IfcWallType_STANDARD
 #endif	
 	);
 	file.addBuildingProduct(east_wall);
 
-	file.setSurfaceColour(clipped_wall_body_rep, wall_colour);
-
 	// The east wall is copied to the west location of the house
 	IfcSchema::IfcWallStandardCase* west_wall = new IfcSchema::IfcWallStandardCase(guid(), file.getSingle<IfcSchema::IfcOwnerHistory>(),
-		S("West wall"), null, null, file.addLocalPlacement(storey_placement, -4820, 2500, 0, 0, 0, 1, 0, -1, 0), file.addMappedItem(clipped_wall_body_rep), null
+		S("West wall"), null, null, file.addLocalPlacement(storey_placement, -4820, 2500, 0, 0, 0, 1, 0, -1, 0), clipped_wall_body_reps[1], null
 #ifdef USE_IFC4
 		, IfcSchema::IfcWallTypeEnum::IfcWallType_STANDARD
 #endif	
 	);
 	file.addBuildingProduct(west_wall);
 
-	for (int i = 0; i < 2; ++i) {
-		// CV-2x3-161: MappedItems are not allowed for Axis representations
-		IfcSchema::IfcWallStandardCase* wall = i == 0 ? east_wall : west_wall;
-		IfcSchema::IfcShapeRepresentation* wall_axis_rep = file.addEmptyRepresentation("Axis", "Curve2D");
-		file.addAxis(wall_axis_rep, 5000);
-		IfcSchema::IfcRepresentation::list::ptr reps = wall->Representation()->Representations();
-		reps->push(wall_axis_rep);
-		wall->Representation()->setRepresentations(reps);
-	}
-
 	// The west wall is assigned an opening element we created for the south wall, opening elements are
 	// not shared accross building elements, even if they share the same representation. Hence, the east
 	// wall will not feature this opening.

src/ifcconvert/IfcConvert.cpp

@@ -32,6 +32,7 @@
 #include <time.h>
 
 #include <boost/program_options.hpp>
+#include <boost/algorithm/string.hpp>
 
 #include "../ifcgeom/IfcGeomIterator.h"
 
@@ -199,9 +200,8 @@ int main(int argc, char** argv) {
 	// Gets the set ifc types to be ignored from the command line. 
 	std::set<std::string> entities;
 	for (std::vector<std::string>::const_iterator it = entity_vector.begin(); it != entity_vector.end(); ++it) {
-		std::string lowercase_type = *it;
-		std::transform(lowercase_type.begin(), lowercase_type.end(), lowercase_type.begin(), ::tolower);
-		entities.insert(lowercase_type);
+		const std::string& mixed_case_type = *it;
+		entities.insert(boost::to_lower_copy(mixed_case_type));
 	}
 	
 	const std::string input_filename = vmap["input-file"].as<std::string>();
@@ -217,7 +217,7 @@ int main(int argc, char** argv) {
 	}
 
 	std::string output_extension = output_filename.substr(output_filename.size()-4);
-	std::transform(output_extension.begin(), output_extension.end(), output_extension.begin(), ::tolower);
+	boost::to_lower(output_extension);
 
 	// If no entities are specified these are the defaults to skip from output
 	if (entity_vector.empty()) {

src/ifcconvert/IgesSerializer.h

@@ -45,6 +45,7 @@ public:
 	void setUnitNameAndMagnitude(const std::string& /*name*/, float magnitude) {
 		const char* symbol = getSymbolForUnitMagnitude(magnitude);
 		if (symbol) {
+			Interface_Static::SetCVal("xstep.cascade.unit", symbol);
 			Interface_Static::SetCVal("write.iges.unit", symbol);
 		}
 	}

src/ifcconvert/OpenCascadeBasedSerializer.cpp

@@ -40,20 +40,14 @@ void OpenCascadeBasedSerializer::write(const IfcGeom::BRepElement<double>* o) {
 	for (IfcGeom::IfcRepresentationShapeItems::const_iterator it = o->geometry().begin(); it != o->geometry().end(); ++ it) {
 		gp_GTrsf gtrsf = it->Placement();
 
-		const std::vector<double>& matrix = o->transformation().matrix().data();
-		
-		// Convert the matrix back into a transformation object. The tolerance values
-		// are taken into consideration to reconstruct the form of the transformation.
-		gp_Trsf o_trsf;
-		o_trsf.SetValues(
-			matrix[0], matrix[3], matrix[6], matrix[ 9],
-			matrix[1], matrix[4], matrix[7], matrix[10], 
-			matrix[2], matrix[5], matrix[8], matrix[11]
-#if OCC_VERSION_HEX < 0x60800
-			, Precision::Angular(), Precision::Confusion()
-#endif
-		);
+		const gp_Trsf& o_trsf = o->transformation().data();
 		gtrsf.PreMultiply(o_trsf);
+
+		if (o->geometry().settings().convert_back_units()) {
+			gp_Trsf scale;
+			scale.SetScaleFactor(1.0 / o->geometry().settings().unit_magnitude());
+			gtrsf.PreMultiply(scale);
+		}
 		
 		const TopoDS_Shape& s = it->Shape();			
 			

src/ifcconvert/StepSerializer.h

@@ -51,6 +51,7 @@ public:
 	void setUnitNameAndMagnitude(const std::string& /*name*/, float magnitude) {
 		const char* symbol = getSymbolForUnitMagnitude(magnitude);
 		if (symbol) {
+			Interface_Static::SetCVal("xstep.cascade.unit", symbol);
 			Interface_Static::SetCVal("write.step.unit", symbol);
 		}
 	}

src/ifcconvert/SvgSerializer.cpp

@@ -217,17 +217,7 @@ void SvgSerializer::write(const IfcGeom::BRepElement<double>* o) {
 	for (IfcGeom::IfcRepresentationShapeItems::const_iterator it = o->geometry().begin(); it != o->geometry().end(); ++ it) {
 		gp_GTrsf gtrsf = it->Placement();
 		
-		gp_Trsf o_trsf;
-		const std::vector<double>& matrix = o->transformation().matrix().data();
-		o_trsf.SetValues(
-			matrix[0], matrix[3], matrix[6], matrix[ 9],
-			matrix[1], matrix[4], matrix[7], matrix[10], 
-			matrix[2], matrix[5], matrix[8], matrix[11]
-#if OCC_VERSION_HEX < 0x60800
-			, Precision::Angular(), Precision::Confusion()
-#endif
-		);
-		gtrsf.PreMultiply(o_trsf);
+		const gp_Trsf& o_trsf = o->transformation().data();
 		const TopoDS_Shape& s = it->Shape();			
 			
 		bool trsf_valid = false;

src/ifcconvert/WavefrontObjSerializer.cpp

@@ -17,12 +17,13 @@
  *                                                                              *
  ********************************************************************************/
 
+#include <limits>
+#include <iomanip>
+
 #include "../ifcgeom/IfcGeomRenderStyles.h"
 
 #include "WavefrontObjSerializer.h"
 
-#include <iomanip>
-
 bool WaveFrontOBJSerializer::ready() {
 	return obj_stream.is_open() && mtl_stream.is_open();
 }
@@ -70,6 +71,8 @@ void WaveFrontOBJSerializer::write(const IfcGeom::TriangulationElement<double>*
 	obj_stream << "g " << o->unique_id() << "\n";
 	obj_stream << "s 1" << "\n";
 
+	obj_stream << std::setprecision(std::numeric_limits<double>::digits10);
+
 	const IfcGeom::Representation::Triangulation<double>& mesh = o->geometry();
 	
 	const int vcount = (int)mesh.verts().size() / 3;

src/ifcgeom/IfcGeom.h

@@ -121,7 +121,7 @@ public:
 	double face_area(const TopoDS_Face& f);
 	void apply_tolerance(TopoDS_Shape& s, double t);
 	void setValue(GeomValue var, double value);
-	double getValue(GeomValue var);
+	double getValue(GeomValue var) const;
 	bool fill_nonmanifold_wires_with_planar_faces(TopoDS_Shape& shape);
 	void remove_redundant_points_from_loop(TColgp_SequenceOfPnt& polygon, bool closed, double tol=-1.);
 

src/ifcgeom/IfcGeomFunctions.cpp

@@ -160,10 +160,15 @@ bool IfcGeom::Kernel::convert_openings(const IfcSchema::IfcProduct* entity, cons
 		IfcSchema::IfcRelVoidsElement* v = *it;
 		IfcSchema::IfcFeatureElementSubtraction* fes = v->RelatedOpeningElement();
 		if ( fes->is(IfcSchema::Type::IfcOpeningElement) ) {
+			if (!fes->hasRepresentation()) continue;
 
 			// Convert the IfcRepresentation of the IfcOpeningElement
 			gp_Trsf opening_trsf;
-			IfcGeom::Kernel::convert(fes->ObjectPlacement(),opening_trsf);
+			if (fes->hasObjectPlacement()) {
+				try {
+					convert(fes->ObjectPlacement(),opening_trsf);
+				} catch (...) {}
+			}
 
 			// Move the opening into the coordinate system of the IfcProduct
 			opening_trsf.PreMultiply(entity_trsf.Inverted());
@@ -302,10 +307,15 @@ bool IfcGeom::Kernel::convert_openings_fast(const IfcSchema::IfcProduct* entity,
 		IfcSchema::IfcRelVoidsElement* v = *it;
 		IfcSchema::IfcFeatureElementSubtraction* fes = v->RelatedOpeningElement();
 		if ( fes->is(IfcSchema::Type::IfcOpeningElement) ) {
+			if (!fes->hasRepresentation()) continue;
 
 			// Convert the IfcRepresentation of the IfcOpeningElement
 			gp_Trsf opening_trsf;
-			IfcGeom::Kernel::convert(fes->ObjectPlacement(),opening_trsf);
+			if (fes->hasObjectPlacement()) {
+				try {
+					convert(fes->ObjectPlacement(),opening_trsf);
+				} catch (...) {}
+			}
 
 			// Move the opening into the coordinate system of the IfcProduct
 			opening_trsf.PreMultiply(entity_trsf.Inverted());
@@ -553,7 +563,7 @@ void IfcGeom::Kernel::setValue(GeomValue var, double value) {
 	}
 }
 
-double IfcGeom::Kernel::getValue(GeomValue var) {
+double IfcGeom::Kernel::getValue(GeomValue var) const {
 	switch (var) {
 	case GV_DEFLECTION_TOLERANCE:
 		return deflection_tolerance;
@@ -774,8 +784,14 @@ bool IfcGeom::Kernel::flatten_shape_list(const IfcGeom::IfcRepresentationShapeIt
 			_trsf = trsf.Trsf();
 			trsf_valid = true;
 		} catch (...) {}
-		const TopoDS_Shape moved_shape = trsf_valid ? merged.Moved(_trsf) :
-			BRepBuilderAPI_GTransform(merged,trsf,true).Shape();
+
+		const TopoDS_Shape moved_shape = trsf.Form() == gp_Identity
+			? merged
+			: (
+			trsf_valid 
+			? merged.Moved(_trsf)
+			: BRepBuilderAPI_GTransform(merged,trsf,true).Shape()
+			);
 
 		if (shapes.size() == 1) {
 			result = moved_shape;
@@ -807,6 +823,10 @@ bool IfcGeom::Kernel::flatten_shape_list(const IfcGeom::IfcRepresentationShapeIt
 		}
 	}
 
+	if (!fuse) {
+		result = compound;
+	}
+
 	const bool success = !result.IsNull();
 	if (success) {
 		const double precision = getValue(GV_PRECISION);

src/ifcgeom/IfcGeomIterator.h

@@ -180,13 +180,15 @@ namespace IfcGeom {
 					// by the parent's context inverse attributes.
 					continue;
 				}
-				if (context->hasContextType()) {
-					std::string context_type_lc = context->ContextType();
-					std::transform(context_type_lc.begin(), context_type_lc.end(), context_type_lc.begin(), ::tolower);
-					if (context_types.find(context_type_lc) != context_types.end()) {
-						filtered_contexts->push(context);
+				try {
+					if (context->hasContextType()) {
+						std::string context_type = context->ContextType();
+						boost::to_lower(context_type);
+						if (context_types.find(context_type) != context_types.end()) {
+							filtered_contexts->push(context);
+						}
 					}
-				}
+				} catch (const IfcParse::IfcException&) {}
 			}
 
 			// In case no contexts are identified based on their ContextType, all contexts are
@@ -204,10 +206,12 @@ namespace IfcGeom {
 				IfcSchema::IfcGeometricRepresentationContext* context = *it;
 
 				representations->push(context->RepresentationsInContext());
-				if (context->hasPrecision() && context->Precision() < lowest_precision_encountered) {
-					lowest_precision_encountered = context->Precision();
-					any_precision_encountered = true;
-				}
+				try {
+					if (context->hasPrecision() && context->Precision() < lowest_precision_encountered) {
+						lowest_precision_encountered = context->Precision();
+						any_precision_encountered = true;
+					}
+				} catch (const IfcParse::IfcException&) {}
 				IfcSchema::IfcGeometricRepresentationSubContext::list::ptr sub_contexts = context->HasSubContexts();
 				for (jt = sub_contexts->begin(); jt != sub_contexts->end(); ++jt) {
 					representations->push((*jt)->RepresentationsInContext());

src/ifcgeom/IfcGeomShapes.cpp

@@ -99,10 +99,15 @@
 #include "../ifcgeom/IfcGeom.h"
 
 bool IfcGeom::Kernel::convert(const IfcSchema::IfcExtrudedAreaSolid* l, TopoDS_Shape& shape) {
+	const double height = l->Depth() * getValue(GV_LENGTH_UNIT);
+	if (height < getValue(GV_PRECISION)) {
+		Logger::Message(Logger::LOG_ERROR, "Non-positive extrusion height encountered for:", l->entity);
+		return false;
+	}
+
 	TopoDS_Shape face;
 	if ( !convert_face(l->SweptArea(),face) ) return false;
 
-	const double height = l->Depth() * getValue(GV_LENGTH_UNIT);
 	gp_Trsf trsf;
 	IfcGeom::Kernel::convert(l->Position(),trsf);
 

src/ifcgeom/IfcGeomWires.cpp

@@ -255,7 +255,7 @@ bool IfcGeom::Kernel::convert(const IfcSchema::IfcTrimmedCurve* l, TopoDS_Wire&
 				flts[1] -= M_PI / 2.;
 			}
 		}
-		if ( isConic && ALMOST_THE_SAME(fmod(flts[1]-flts[0],(double)(M_PI*2.0)),0.0f) ) {
+		if ( isConic && ALMOST_THE_SAME(fmod(flts[1]-flts[0],M_PI*2.),0.) ) {
 			w.Add(BRepBuilderAPI_MakeEdge(curve));
 		} else {
 			BRepBuilderAPI_MakeEdge e (curve,flts[0],flts[1]);

src/ifcgeom/IfcRegister.cpp

@@ -24,6 +24,15 @@ using namespace IfcSchema;
 using namespace IfcUtil;
 
 bool IfcGeom::Kernel::convert_shapes(const IfcBaseClass* l, IfcRepresentationShapeItems& r) {
+	if (shape_type(l) != ST_SHAPELIST) {
+		TopoDS_Shape shp;
+		if (convert_shape(l, shp)) {
+			r.push_back(IfcGeom::IfcRepresentationShapeItem(shp, get_style(l->as<IfcSchema::IfcRepresentationItem>())));
+			return true;
+		}
+		return false;
+	}
+
 #include "IfcRegisterConvertShapes.h"
 	Logger::Message(Logger::LOG_ERROR,"No operation defined for:",l->entity);
 	return false;

src/ifcopenshell-python/ifcopenshell/geom/__init__.py

@@ -31,7 +31,7 @@ def has_occ():
 has_occ = has_occ()
 wrap_shape_creation = lambda settings, shape: shape
 if has_occ:
-    import occ_utils as utils
+    from . import occ_utils as utils
     wrap_shape_creation = lambda settings, shape: utils.create_shape_from_serialization(shape) if getattr(settings, 'use_python_opencascade', False) else shape
 
 

src/ifcopenshell-python/ifcopenshell/geom/occ_utils.py

@@ -52,8 +52,14 @@ def get_bounding_box_center(bbox):
 def create_shape_from_serialization(brep_object):
     brep_data, occ_shape = None, None
     
-    try: brep_data = brep_object.geometry.brep_data
-    except: pass    
+    is_product_shape = True
+    try:
+        brep_data = brep_object.geometry.brep_data
+    except: 
+        try: 
+            brep_data = brep_object.brep_data
+            is_product_shape = False
+        except: pass
     if not brep_data: return tuple(brep_object, None)
     
     try:
@@ -62,5 +68,8 @@ def create_shape_from_serialization(brep_object):
         occ_shape = ss.Shape(ss.NbShapes())
     except: pass
     
-    return tuple(brep_object, occ_shape)
+    if is_product_shape:
+        return tuple(brep_object, occ_shape)
+    else:
+        return occ_shape
 

src/ifcparse/IfcParse.cpp

@@ -970,7 +970,7 @@ bool IfcFile::Init(IfcParse::IfcSpfStream* s) {
 					const std::string guid = ifc_root->GlobalId();
 					if ( byguid.find(guid) != byguid.end() ) {
 						std::stringstream ss;
-						ss << "Overwriting entity with guid " << guid;
+						ss << "Instance encountered with non-unique GlobalId " << guid;
 						Logger::Message(Logger::LOG_WARNING,ss.str());
 					}
 					byguid[guid] = ifc_root;
@@ -992,7 +992,7 @@ bool IfcFile::Init(IfcParse::IfcSpfStream* s) {
 			
 			if ( byid.find(currentId) != byid.end() ) {
 				std::stringstream ss;
-				ss << "Overwriting entity with id " << currentId;
+				ss << "Overwriting instance with name #" << currentId;
 				Logger::Message(Logger::LOG_WARNING,ss.str());
 			}
 			byid[currentId] = entity;

src/ifcparse/IfcUtil.h

@@ -89,6 +89,13 @@ namespace IfcUtil {
 				? static_cast<T*>(this) 
 				: static_cast<T*>(0);
 		}
+
+		template <class T>
+		const T* as() const {
+			return is(T::Class()) 
+				? static_cast<const T*>(this) 
+				: static_cast<const T*>(0);
+		}
 	};
 
 	class IfcBaseEntity : public IfcBaseClass {

src/ifcparse/IfcWrite.cpp

@@ -19,6 +19,7 @@
 
 #include <iomanip>
 #include <locale>
+#include <limits>
 
 #include <boost/algorithm/string.hpp>
 
@@ -328,7 +329,7 @@ private:
 	std::string format_double(const double& d) {
 		std::ostringstream oss;
 		oss.imbue(std::locale::classic());
-		oss << std::setprecision(15) << d;
+		oss << std::setprecision(std::numeric_limits<double>::digits10) << d;
 		const std::string str = oss.str();
 		oss.str("");
 		std::string::size_type e = str.find('e');

src/ifcwrap/IfcGeomWrapper.i

@@ -72,17 +72,35 @@
 	}
 }
 
+// A visitor
+%{
+struct ShapeRTTI : public boost::static_visitor<PyObject*>
+{
+    PyObject* operator()(IfcGeom::Element<double>* elem) const {
+		IfcGeom::SerializedElement<double>* serialized_elem = dynamic_cast<IfcGeom::SerializedElement<double>*>(elem);
+		IfcGeom::TriangulationElement<double>* triangulation_elem = dynamic_cast<IfcGeom::TriangulationElement<double>*>(elem);
+		if (triangulation_elem) {
+			return SWIG_NewPointerObj(SWIG_as_voidptr(triangulation_elem), SWIGTYPE_p_IfcGeom__TriangulationElementT_double_t, SWIG_POINTER_OWN);
+		} else if (serialized_elem) {
+			return SWIG_NewPointerObj(SWIG_as_voidptr(serialized_elem), SWIGTYPE_p_IfcGeom__SerializedElementT_double_t, SWIG_POINTER_OWN);
+		}
+	}
+    PyObject* operator()(IfcGeom::Representation::Representation* representation) const {
+		IfcGeom::Representation::Serialization* serialized_representation = dynamic_cast<IfcGeom::Representation::Serialization*>(representation);
+		IfcGeom::Representation::Triangulation<double>* triangulated_representation = dynamic_cast<IfcGeom::Representation::Triangulation<double>*>(representation);
+		if (serialized_representation) {
+			return SWIG_NewPointerObj(SWIG_as_voidptr(serialized_representation), SWIGTYPE_p_IfcGeom__Representation__Serialization, SWIG_POINTER_OWN);
+		} else if (triangulated_representation) {
+			return SWIG_NewPointerObj(SWIG_as_voidptr(triangulated_representation), SWIGTYPE_p_IfcGeom__Representation__TriangulationT_double_t, SWIG_POINTER_OWN);
+		}
+	}
+};
+%}
+
 // Note that these elements ARE to be owned by SWIG/Python
 %typemap(out) boost::variant<IfcGeom::Element<double>*, IfcGeom::Representation::Representation*> {
 	// See which type is set and return appropriate
-	IfcGeom::Element<double>* elem = boost::get<IfcGeom::Element<double>*>($1);
-	IfcGeom::SerializedElement<double>* serialized_elem = dynamic_cast<IfcGeom::SerializedElement<double>*>(elem);
-	IfcGeom::TriangulationElement<double>* triangulation_elem = dynamic_cast<IfcGeom::TriangulationElement<double>*>(elem);
-	if (triangulation_elem) {
-		$result = SWIG_NewPointerObj(SWIG_as_voidptr(triangulation_elem), SWIGTYPE_p_IfcGeom__TriangulationElementT_double_t, SWIG_POINTER_OWN);
-	} else if (serialized_elem) {
-		$result = SWIG_NewPointerObj(SWIG_as_voidptr(serialized_elem), SWIGTYPE_p_IfcGeom__SerializedElementT_double_t, SWIG_POINTER_OWN);
-	}
+	$result = boost::apply_visitor(ShapeRTTI(), $1);
 }
 
 // This does not seem to work:
@@ -218,25 +236,25 @@
 
 %inline %{
 	boost::variant<IfcGeom::Element<double>*, IfcGeom::Representation::Representation*> create_shape(IfcGeom::IteratorSettings& settings, IfcParse::IfcLateBoundEntity* instance, IfcParse::IfcLateBoundEntity* representation = 0) {
+		IfcParse::IfcFile* file = instance->entity->file;
+		IfcSchema::IfcProject::list::ptr projects = file->entitiesByType<IfcSchema::IfcProject>();
+		if (projects->size() != 1) {
+			throw IfcParse::IfcException("Not a single IfcProject instance");
+		}
+		IfcSchema::IfcProject* project = *projects->begin();
+			
+		IfcGeom::Kernel kernel;
+		kernel.setValue(IfcGeom::Kernel::GV_MAX_FACES_TO_SEW, settings.sew_shells() ? 1000 : -1);
+		kernel.setValue(IfcGeom::Kernel::GV_DIMENSIONALITY, (settings.include_curves() ? (settings.exclude_solids_and_surfaces() ? -1. : 0.) : +1.));
+		std::pair<std::string, double> length_unit = kernel.initializeUnits(project->UnitsInContext());
+			
 		if (instance->is(IfcSchema::Type::IfcProduct)) {
 			if (representation) {
 				if (!representation->is(IfcSchema::Type::IfcRepresentation)) {
 					throw IfcParse::IfcException("Supplied representation not of type IfcRepresentation");
 				}
 			}
-
-			IfcParse::IfcFile* file = instance->entity->file;
-			
-			IfcSchema::IfcProject::list::ptr projects = file->entitiesByType<IfcSchema::IfcProject>();
-			if (projects->size() != 1) {
-				throw IfcParse::IfcException("Not a single IfcProject instance");
-			}
-			IfcSchema::IfcProject* project = *projects->begin();
-			
-			IfcGeom::Kernel kernel;
-			kernel.setValue(IfcGeom::Kernel::GV_MAX_FACES_TO_SEW, settings.sew_shells() ? 1000 : -1);
-			kernel.setValue(IfcGeom::Kernel::GV_DIMENSIONALITY, (settings.include_curves() ? (settings.exclude_solids_and_surfaces() ? -1. : 0.) : +1.));
-
+		
 			IfcSchema::IfcProduct* product = (IfcSchema::IfcProduct*) instance;
 
 			if (!representation && !product->hasRepresentation()) {
@@ -318,7 +336,6 @@
 			if (context->hasPrecision()) {
 				precision = context->Precision();
 			}
-			std::pair<std::string, double> length_unit = kernel.initializeUnits(project->UnitsInContext());
 			precision *= length_unit.second;
 
 			// Some arbitrary factor that has proven to work better for the models in the set of test files.
@@ -342,7 +359,28 @@
 				throw IfcParse::IfcException("No element to return based on provided settings");
 			}
 		} else {
-			throw IfcParse::IfcException("Only obtaining representations for IfcProduct instances is currently supported");
+			if (!representation) {
+				if (instance->is(IfcSchema::Type::IfcRepresentationItem) || instance->is(IfcSchema::Type::IfcRepresentation)) {
+					IfcGeom::IfcRepresentationShapeItems shapes;
+					if (kernel.convert_shapes(instance, shapes)) {
+						IfcGeom::ElementSettings element_settings(settings, kernel.getValue(IfcGeom::Kernel::GV_LENGTH_UNIT), IfcSchema::Type::ToString(instance->type()));
+						IfcGeom::Representation::BRep brep(element_settings, instance->entity->id(), shapes);
+						try {
+							if (settings.use_brep_data()) {
+								return new IfcGeom::Representation::Serialization(brep);
+							} else if (!settings.disable_triangulation()) {
+								return new IfcGeom::Representation::Triangulation<double>(brep);
+							}
+						} catch (...) {
+							throw IfcParse::IfcException("Error during shape serialization");
+						}
+					} else {
+						throw IfcParse::IfcException("Geometrical element not understood");
+					}
+				}
+			} else {
+				throw IfcParse::IfcException("Invalid additional representation specified");
+			}
 		}
 	}
 %}