Allow IfcStructural* elements to be exported. See #756.

src/ifcblenderexport/blenderbim/schema.py

@@ -0,0 +1,33 @@
+import os
+import json
+import ifcopenshell
+
+cwd = os.path.dirname(os.path.realpath(__file__))
+
+class IfcSchema():
+    def __init__(self):
+        self.schema_dir = os.path.join(cwd, 'schema') # TODO: make configurable
+        self.products = ['IfcElement', 'IfcSpatialStructureElement', 'IfcStructural']
+        self.elements = {}
+        print(os.path.join(self.schema_dir, 'IFC4_ADD2.ifc'))
+        self.property_file = ifcopenshell.open(os.path.join(self.schema_dir, 'IFC4_ADD2.ifc'))
+        self.psets = {}
+        self.qtos = {}
+        self.load()
+
+    def load(self):
+        for product in self.products:
+            with open(os.path.join(self.schema_dir, f'{product}_IFC4.json')) as f:
+                setattr(self, product, json.load(f))
+                self.elements.update(getattr(self, product))
+
+        with open(os.path.join(self.schema_dir, 'ifc_types_IFC4.json')) as f:
+            self.type_map = json.load(f)
+
+        for property in self.property_file.by_type('IfcPropertySetTemplate'):
+            if property.Name[0:4] == 'Qto_':
+                # self.qtos.append({ })
+                pass
+            else:
+                self.psets[property.Name] = {
+                    'HasPropertyTemplates': {p.Name: p for p in property.HasPropertyTemplates}}